Classification: Unclassified BM Code: A-27 Issue Purpose AFU September, 2005

Sakhalin Energy Investment Company LTD.

Ecological-fisheries characteristics of bays of the Northeastern Sakhalin

Эколого-рыбохозяйственная характеристика заливов северо-восточного Сахалина

Document Number: 0000-S-90-04-T-7964-00-D Revision 01

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FISHERY STATE COMMITTEE OF RUSSIAN FEDERATION Federal State Unitary Enterprise Sakhalin Research Institute of Fisheries and Oceanography (SakhNIRO)

«A P P R O V E» Director of SakhNIRO

______V.I. Radchenko «____» ______2003

REPORT on the implementation of scientific-research works according to the Agreement № Y – 00571 on the subject :

“ECOLOGICAL-FISHERIES CHARACTERISTICS OF BAYS OF THE NORTHEASTERN SAKHALIN”

General management: Head of DAE, c.b.s. A. D. Samatov

Yuzhno-Sakhalinsk, 2002

2 ABSTRACT

P. 288, Tab. 155, Fig. 110, Ref. 139

PHYSIC-GEOGRAPHIC CHARACTERISTIC, HYDROLOGIC-HYDROCHEMICAL PARAMETERS, PARTICLE-SIZE COMPOSITION, PETROLEUM HYDROCARBONS, CHLORORGANIC PESTICIDES, PHENOLS, METALS, MICROBIAL INDICATION, PHYTOPLANKTON, ZOOPLANKTON, BENTHOS, ICHTHYOFAUNA, FISHERY PECULIARITIES

In this report the ecological-fisheries characteristics of the northeastern Sakhalin bays (Piltun, Chaivo, Nyisky, Nabil, and Lunsky) including a general physic-geographic characteristic; description of hydrologic-hydrochemical parameters and particle-size composition of bottom sediments; evaluation of pollutant contents in bottom sediments and biota; microbial indication and characteristic of plankton and benthos communities; description of ichthyofauna and fishery peculiarities are presented based on the archive data and the 2002 surveys.

3 EXECUTORS

1. Samatov A.D., c.b.s., Head of DAE General management, ABSTRACT, INTRODUCTION, editing 2. Koreneva T.G., cheif engineer of Resp.executor. Sections 1.1, 1.2, 2.2, 2.3, 2.4, Laboratory of Analytical Researches 3.2, 3.3, 3.4, 4.2, 4.3, 4.4, 5.2, 5.3, 5.4, 6.2, (LAR) 6.3, 6.4, 7.2, 7.3, 7.4 3. Polupanov P.V., s.engineer of Laboratory Sections 2.1, 3.1, 4.1, 5.1, 6.1, 7.1 of Inland Water Bioresources (LIWB) 4. Polteva A.V., r.w. of Laboratory of Fish Sections 2.5, 3.5, 4.5, 5.5, 6.5, 7.5 Disease (LFD) 5. Motylkova I.V., s.assistant of Laboratory Sections 2.6, 3.6, 4.6, 5.6, 6.6, 7.6 of Hydrobiology (LH) 6. Zavarzin D.S., s.engineer, LH Sections 2.7, 3.7, 4.7, 5.7, 6.7, 7.7 7. Labay V.S., Head of LH, c.b.s. Resp.executor. Sections 2.8, 3.8, 4.8, 5.8, 6.8, 7.8 8. Pecheneva N.V., r.w., LH Sections 2.8, 3.8, 4.8, 5.8, 6.8, 7.8 9. Nikiforov S.N., c.b.s., s.r.w., LIWB Resp.executor. Sections 1.1, 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 10. Ni N.K., s.engineer, LIWB Sections 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 11. Nikitin V.D., j.r.w., LIWB Sections 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 12. Shepeleva O.N., r.w. of Laboratory of Sections 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 Coastal Bioresources (LCB) 13. Ivshina E.R., j.r.w., LCB Sections 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 14. Shershnev A.P., chief r.w. of Laboratory Sections 2.9, 3.9, 4.9, 5.9, 6.9, 7.9 of Salmonid Fishes (LSF), c.b.s. 15. Tarasova L.I., Head of Group of Translation Scientific-Technical Information (GSTI)

4 CONTENTS

LIST OF CONVENTIONAL DESIGNATIONS AND ABBREVIATIONS 7 INTRODUCTION 8 1. MATERIAL AND METHODS 9 1.1 Methods of field studies 9 1.1.1. Water sampling for chemical analysis 9 1.1.2. Bottom sediments sampling for a quantitative determination of the petroleum hydrocarbon contents 12 1.1.3. Hydrobiological sampling 13 1.2. Methods of laboratory studies 13 1.2.1. Chemical analysis of water samples 13 1.2.2. Quality control of hydrochemical studies 15 1.2.3. Determination of a total content of petroleum hydrocarbons in bottom sediments 15 1.2.4. Quality control of determination of the petroleum hydrocarbon contents in bottom sediments 17 1.2.5. Processing the hydrobiological samples 18 2. PILTUN BAY 19 2.1. General physic-geographic characteristics of the Piltun Bay 19 2.2. Hydrology and hydrochemistry of the Piltun Bay 20 2.2.1. Results of hydrologic-hydrochemical researches by the archive and 20 literary data 2.2.2. Results of hydrologic-hydrochemical researches in 2002 22 2.3. Particle-size composition of bottom sediments in the Piltun Bay 23 2.4. Content of pollutants in the Piltun Bay 25 2.4.1. Content of pollutants in bottom sediments by the archive and literary data 25 2.4.2. Content of pollutants in biota 27 2.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 30 2.5. Microbiological researches in the Piltun Bay 31 2.6. Phytoplankton of the Piltun Bay 32 2.6.1. Description of phytoplankton by the archive and literary data 32 2.6.2. Characteristic of phytoplankton in 2002 32 2.7. Zooplankton of the Piltun Bay 33 2.7.1. Description of zooplankton by the archive and literary data 33 2.7.2. Characteristic of zooplankton in 2002 35 2.8. Benthos of the Piltun Bay 39 2.8.1. General characteristics of benthos 39 2.8.2. Benthos communities 42 2.9. Ichthyofauna of the Piltun Bay 52 2.9.1. Main commercial species 55 2.9.2. Secondary commercial and perspective for fishery species 58 2.9.3. Mass non-commercial species 59 3. CHAIVO BAY 61 3.1. General physic-geographic characteristics of the Chaivo Bay 61 3.2. Hydrology and hydrochemistry of the Chaivo Bay 62 3.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data 62 3.2.2. Results of hydrologic-hydrochemical researches in 2002 63 3.3. Particle-size composition of bottom sediments in the Chaivo Bay 65 3.4. Content of pollutants in the Chaivo Bay 65 5 3.4.1. Content of pollutants in bottom sediments by the archive and literary data 65 3.4.2. Content of pollutants in biota 68 3.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 68 3.5. Microbiological researches in the Chaivo Bay 69 3.6. Phytoplankton of the Chaivo Bay 70 3.6.1. Description of phytoplankton by the archive and literary data 70 3.6.2. Characteristic of phytoplankton in 2002 70 3.7. Zooplankton of the Chaivo Bay 71 3.7.1. Description of zooplankton by the archive and literary data 71 3.7.2. Characteristic of zooplankton in 2002 72 3.8. Benthos of the Chaivo Bay 74 3.8.1. General characteristics of benthos 74 3.8.2. Benthos communities 80 3.9. Ichthyofauna of the Chaivo Bay 84 3.9.1. Main commercial species 86 3.9.2. Secondary commercial and perspective for fishery species 92 3.9.3. Mass non-commercial species 102 4. NYISKY BAY 104 4.1. General physic-geographic characteristics of the Nyisky Bay 104 4.2. Hydrology and hydrochemistry of the Nyisky Bay 106 4.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data 106 4.2.2. Results of hydrologic-hydrochemical researches in 2002 109 4.3. Particle-size composition of bottom sediments in the Nyisky Bay 110 4.4. Content of pollutants in the Nyisky Bay 111 4.4.1. Content of pollutants in bottom sediments by the archive and literary data 111 4.4.2. Content of pollutants in biota 116 4.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 118 4.5. Microbiological researches in the Nyisky Bay 119 4.6. Phytoplankton of the Nyisky Bay 126 4.6.1. Description of phytoplankton by the archive and literary data 126 4.6.2. Characteristic of phytoplankton in 2002 126 4.7. Zooplankton of the Nyisky Bay 128 4.7.1. Description of zooplankton by the archive and literary data 128 4.7.2. Characteristic of zooplankton in 2002 130 4.8. Benthos of the Nyisky Bay 132 4.8.1. General characteristics of benthos 132 4.8.2. Benthos communities 137 4.9. Ichthyofauna of the Nyisky Bay 140 4.9.1. Main commercial species 142 4.9.2. Secondary commercial and perspective for fishery species 150 5. NABIL BAY 153 5.1. General physic-geographic characteristics of the Nabil Bay 153 5.2. Hydrology and hydrochemistry of the Nabil Bay 154 5.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data 154 5.2.2. Results of hydrologic-hydrochemical researches in 2002 156 5.3. Particle-size composition of bottom sediments in the Nabil Bay 157 5.4. Content of pollutants in the Nabil Bay 158 5.4.1. Content of pollutants in bottom sediments by the archive and literary data 158 5.4.2. Content of pollutants in biota 163 5.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 167 6 5.5. Microbiological researches in the Nabil Bay 167 5.6. Phytoplankton of the Nabil Bay 168 5.6.1. Description of phytoplankton by the archive and literary data 168 5.6.2. Characteristic of phytoplankton in 2002 169 5.7. Zooplankton of the Nabil Bay 170 5.7.1. Description of zooplankton by the archive and literary data 170 5.7.2. Characteristic of zooplankton in 2002 170 5.8. Benthos of the Nabil Bay 172 5.8.1. General characteristics of benthos 172 5.8.2. Benthos communities 175 5.9. Ichthyofauna of the Nabil Bay 181 5.9.1. Main commercial species 182 6. LUNSKY BAY 186 6.1. General physic-geographic characteristics of the Lunsky Bay 186 6.2. Hydrology and hydrochemistry of the Lunsky Bay 188 6.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data 188 6.2.2. Results of hydrologic-hydrochemical researches in 2002 189 6.3. Particle-size composition of bottom sediments in the Lunsky Bay 191 6.4. Content of pollutants in the Lunsky Bay 192 6.4.1. Content of pollutants in bottom sediments by the archive and literary data 192 6.4.2. Content of petroleum hydrocarbons in bottom sediments in 2002 194 6.5. Microbiological researches in the Lunsky Bay 194 6.6. Phytoplankton of the Lunsky Bay 198 6.6.1. Description of phytoplankton by the archive and literary data 198 6.6.2. Characteristic of phytoplankton in 2002 198 6.7. Zooplankton of the Lunsky Bay 199 6.7.1. Description of zooplankton by the archive and literary data 199 6.7.2. Characteristic of zooplankton in 2002 199 6.8. Benthos of the Lunsky Bay 202 6.8.1. General characteristics of benthos 202 6.9. Ichthyofauna of the Lunsky Bay 207 6.9.1. Main commercial species 209 6.9.2. Secondary commercial and perspective for fishery species 212 6.9.3. Mass non-commercial species 216 7. COMPARATIVE CHARACTERISTIC OF BAYS 218 7.1. General physic-geographic characteristics 218 7.2. Hydrochemical parameters 219 7.3. Particle-size composition of bottom sediments 220 7.4. Pollutants 221 7.5. Microbial indication 223 7.6. Phytoplankton 225 7.7. Zooplankton 226 7.8. Benthos 226 7.9. Ichthyofauna and fishery in the bays 229 REFERENCES 246 APPENDICES 254

7 LIST OF CONVENTIONAL DESIGNATIONS AND ABBREVIATIONS

BO – bottom sediments PHC – petroleum hydrocarbons HC – hydrocarbons COP – chlororganic pesticides HCCH – hexochlorocyclohexane DDT – 4, 4’ – dichlorodiphenyltrichloroethane DDE – 1, 1 – di (4’ – chlorophenyl) – 2’, 2 – dichloroethylene DDD – 1, 1 – di (4’ – chlorophenyl) – 2’, 2 – dichloroethane PCB – polychlorinated biphenyls PAHC – polyaromatic hydrocarbons HM – heavy metals BOD – biochemical oxygen demand COD – chemical oxygen demand RFA – roentgen fluorescent analysis AAS – atomic-absorption spectrophotometry

8 INTRODUCTION

In this report the ecological-fisheries characteristics of the northeastern Sakhalin bays (Piltun, Chaivo, Nyisky, Nabil, and Lunsky) are presented. The necessity in studying shallow areas of the semi-closed and closed lagoon types is caused by their uniqueness and higher vulnerability. The uniqueness of these water bodies is determined by the high bioproductivity and fisheries importance caused by a specific character of abiotic factors including the bottom and shore relieves, composition of bottom sediments, hydrologic and hydrochemical peculiarities. The vulnerability is determined by a small size of water bodies, instability of structural indices of the hydrobiont communities under the conditions of transitional brackish and freshened zones, occurrence of economic activity, and existing level of anthropogenic pollution. When developing marine oil-gas fields on the Okhotsk Sea shelf in the region of northeastern Sakhalin, it is proposed to construct and then use different objects located on the bays’ area or close to them. The oil-gas projects should be realized with the minimum impact on environment in order to preserve a biodiversity of the unique ecosystems of the bays and to maintain a balance of interests between the fisheries and oil-gas industries. The aim of researches, taking into account the above factors and fisheries importance of the northeastern Sakhalin bays, consists in the complex description of indices of the hydrobiont communities and their habitat, which will be considered as a background regarding to the following long-term developments of the shelf oil-gas fields including the project «Sakhalin-2». The tasks of researches include: • General physic-geographic characteristics; • Description of hydrologic and hydrochemical parameters; • Description of particle-size composition of bottom sediments; • Estimation of pollutant contents in bottom sediments; • Estimation of pollutant contents in biota; • Microbial indication; • Characteristic of plankton communities (phyto- and zooplankton); • Characteristic of benthos communities; • Fisheries characteristic including a description of ichthyofauna and fishery peculiarities. The basic data for describing a background ecological-fisheries characteristic of the bays are: literary information; SakhNIRO archive data presented as the results of complex researches in 1996-2001; materials collected in 2002 according to the work order of the «Sakhalin Energy Investment Company, Ltd.» including the initial data of the instrumental measurements, cameral and analytical processing the samples. When preparing the fisheries characteristic of the bays, the materials collected during the last 10 years both within the scientific-research works and those obtained during the control capture and fishing such objects as salmonid fishes, saffron cod, herring, flounders and other bycatch species have been used. The Book 1 presents the results of researches; the Book 2 presents the initial materials of 2002 including the cards of sample processing, chromatograms, and results of analyses and quality control. 9 1. MATERIAL AND METHODS

The 2002 field researches in the northeastern Sakhalin bays (Piltun, Chaivo, Nyisky, Nabil, and Lunsky) took place from 17 to 30 September (Appendix 1). A total of 50 complex stations have been performed in the bays: by 9-12 stations in each bay (Table 1.1, Fig. 1.1) according to the Appendix B “Scope of work” of the Agreement № Y-00571. The stations were executed using two motor-boats «Favorite-420» with the «Yamaha» engines of 30 horse-power. Coordinates were identified with the help of the satellite navigation instruments GPS-12 and GPS-II+.

Table 1.1 A list of complex stations performed in the northeastern Sakhalin bays in September 2002 Bay Station Date Latitude* Longitude* Depth, m Pi-1 17.09.02 637000 5904000 0,7 Pi-2 17.09.02 640000 5889000 0,9 Pi-3 17.09.02 643000 5877000 0,7 Pi-4 18.09.02 653000 5873000 0,7 Pi-5 18.09.02 652400 5864000 0,4 Piltun Pi-6 18.09.02 651000 5858000 0,4 Pi-7 18.09.02 648700 5862000 0,5 Pi-8 18.09.02 650165 5888511 0,3 Pi-9 19.09.03 649244 5868881 0,9 Pi-10 19.09.03 653300 5870481 0,9 Pi-11 18.09.02 646000 5872000 0,9 Ch-1 21.09.02 651515 5821997 1,0 Ch-2 21.09.02 648507 5816585 1,0 Ch-3 22.09.02 648923 5809616 5,0 Ch-4 22.09.02 648453 5807548 4,5 Chaivo Ch-5 22.09.02 653888 5815508 4,5 Ch-6 22.09.02 648000 5802000 0,4 Ch-7 22.09.02 646012 5803419 1,0 Ch-8 22.09.02 644500 5801500 0,6 Ch-9 22.09.02 646109 5795480 0,6 Ny-1 24.09.02 643500 5781000 0,4 Ny-2 24.09.02 644001 5777000 0,4 Ny-3 24.09.02 644500 5773500 0,6 Ny-4 24.09.02 646500 5774500 2,5 Ny-5 24.09.02 646051 5770755 0,4 Ny-6 24.09.02 646000 5767000 0,2 Nyisky Ny-7 25.09.02 647999 5761500 4,5 Ny-8 25.09.02 650000 5757000 6,0 Ny-9 25.09.02 649027 5756756 0,7 Ny-10 25.09.02 648500 5753000 0,8 Ny-11 25.09.02 649998 5750037 0,4 Ny-12 25.09.02 651999 5752500 3,0 Nb-1 27.09.02 659800 5733000 7,0 Nabil Nb-2 27.09.02 661200 5729400 5,0 Nb-3 27.09.02 659500 5727800 0,8 Nb-4 27.09.02 657792 5724388 0,6 Nb-5 28.09.02 655525 5719304 0,3 Nb-6 28.09.02 659800 5718800 1,8 10 Bay Station Date Latitude* Longitude* Depth, m Nb-7 28.09.02 656212 5710642 1,2 Nb-8 28.09.02 661200 5709900 0,8 Nb-9 27.09.02 662800 5723400 2,0 Lu-1 30.09.02 668100 5691600 0,6 Lu-2 30.09.02 668600 5688150 0,4 Lu-3 30.09.02 670200 5689800 2,0 Lu-4 30.09.02 672300 5688750 0,5 Lunsky Lu-5 30.09.02 672700 5687400 3,0 Lu-6 30.09.02 673300 5685200 0,4 Lu-7 30.09.02 672360 5684100 0,6 Lu-8 30.09.02 672950 5680850 0,5 Lu-9 30.09.02 675600 5677900 0,4 *- coordinates are in the UTM format

Water temperature, salinity, and pH were measured at each station with the help of sounders YSI-63. Water sampling for the chemical analysis was done with the help of 3 and 1— liter bathometers in the surface layer, and at the depths more than 1 m – in the surface and near- bottom horizons. Bottom sediment (BS) samples were collected with the help of Fredinger grab with a clutch square of 0,025 m2.

1.1. Methods of field studies

This section contains a description of methods for collecting materials at the stage of expedition surveys of the northeastern Sakhalin bays in September 2002. 1.1.1. Water sampling for chemical analysis Water sampling from the bays of the northeastern Sakhalin coast for a chemical analysis has been conducted from the rubber motor boat with the help of 2 and 10-liter bathometers in the surface horizon, and at the depths more than 1 m – in the surface and near-bottom horizons. The bathometers’ construction let them to be open under the water surface in order to prevent a sample from the surface pollution. During sampling, water temperature, salinity, and pH were determined at all stations with the help of the multi-component sounder YSI-63, which was calibrated every day before the work starting. Water samples were taken for analysis of the parameters described below. Dissolved oxygen The Vincler’s method was used for determining dissolved oxygen from water samples being taken according to the GOST 17.1.5.05-85, R 52.24.353-94, and RD 52.10.243-92. Sampling was realized with the help of bathometers from the surface or required horizon; a water sample for determining oxygen was taken first from a bathometer. While putting the water samples to an oxygen bottle, a tube of bathometer was lowered up to the bottom of the oxygen bottle. After the bottle was filled up to a throat, its filling was continued until the water being in contact with air occurring in the bottle would be extruded. The tube was taken out without stopping the water flow from the bathometer. Thus, the bottle was filled with a sample up to the edge and had no air bubbles on the walls inside it.

11

Fig. 1.1. A map of study region and location of sampling stations in the northeastern Sakhalin bays in September 2002 12 Dissolved oxygen was fixed with the solutions of manganese chloride and potassium iodide in the caustic potassium immediately after sampling. The numbers of bottles and time of fixation were recorded. Samples were brought to the field chemical laboratory for the further analysis. The fixed samples were kept not more than 24 hours. Biogenic elements Biogenic elements were sampled according to the GOST 17.1.5.05-85, R 52.24.353-94, and RD 52.10.243-92. Water samples were placed into the prepared plastic ware. Samples were fixed with chloroform and freezing after the preliminary filtration with the help of the vacuum pump through the membrane filter with 0.45 mkm in pore diameter. After freezing the samples were brought to the stationary chemical-analytical laboratory for the further analysis. Petroleum hydrocarbons In order to determine a mass concentration of petroleum hydrocarbons, sampling was done according to the GOST 17.1.5.05-85, PND F 14.1:4.128-98. Samples were taken with the help of a fluoroplastic bathometer to the prepared 1-liter bottles from the amber glass. A preserving agent (hexane) was added to each bottle. The bottles were covered with caps with the teflon cover. The petroleum hydrocarbon extraction was carried out in the field laboratory. Hexane extracts were stored in the refrigerating chamber under the temperature not high than 4 °С; further they were delivered to the stationary chemical-analytical laboratory for the further analysis. Chlorophyll “a” In order to analyze a content of chlorophyll “a”, sampling was conducted according to the GOST 17.1.4.02-90. Samples were taken with the help of a bathometer to the two 1,5-liter plastic dark bottles. If the immediate filtration was impossible, they were kept under the temperature of 6°С and lower not more than 2-3 hours. In the field laboratory, samples were filtered on the filter plant using a vacuum pump (pressure differential 0.15-0.20) on the fiberglass filter (0.45 mkm). Immediately after filtering, the filter was dried with the help of filter paper and in the cold airflow, being rolled up in half with sediment inside. Further, filters were curled into the aluminum foil, marked, and stored in the freezing chamber under the temperature (-) 20 °С until delivering to the stationary chemical laboratory. Suspended matters In order to determine a concentration of suspended matters, sampling was done according to the GOST 17.1.5.05-85, RD 52.24.468-95, PND F 14.1:2.110-97. Water samples were placed into the 1,5-liter plastic bottle. In the field laboratory a filtration was conducted through the paper filters (“blue tape”) prepared and reduced to the constant weight under 105 °С. Further, filters were washed with the hot distillate from chlorides (with a test on silver nitrate) and dried on the air. Filters were stored in the freezing chamber until delivering to the stationary chemical laboratory.

1.1.2. Bottom sediments sampling for a quantitative determination of the petroleum hydrocarbon contents The instruments used for sampling and processing the patterns of bottom sediments (BS): Fredinger’s grab, teflon cylinders, rings, and plungers were passed through the preliminary treatment before every use and between stations. The preliminary treatment included both a primary washing with a soap non-containing phosphates, and washing with pure seawater using a nylon brush. Further the instruments were treated with the nitric acid (10-20 %) and organic dissolvent (hexane). Before each sampling, the instruments were cleaned with a soap non- containing phosphates, and washed with seawater. In the periods between stations the instruments were washed with pure seawater. BS sampling for the petroleum hydrocarbons (PHC) analysis was realized at stations with the depth more than 1 m using a Fredinger’s grab with a clutch of 0.025 m2. The grab was created of the stainless steel and covered with Dykor. In order to prevent a sample from the possible contamination, the lubricating matters for moving parts of the grab were not used. 13 Before packing, each sample was visually examined for the pattern quality; after returning the sampler to the boat, it was examined in order to make sure that there was not any disturbance in the sample integrity (drain of water and small BS particles). The natural surface 2-cm layer was sampled for the chemical analysis. At the in-shore stations the surface layer (2 cm) of BS was taken to the preliminary cleaned teflon cylinder with the inside diameter of 6 cm; plungers were used to extract a sample from the cylinder. Sample patterns (approximately 100 g of the wet weight) were placed into the clean 250-ml wide-throat glass jars with teflon caps, treated before with hexane and 10 % nitric acid. The jars were closed, marked, and stored in the freezing chamber under the temperature (-) 20 °С until delivering to the stationary chemical laboratory. In general, 50 stations were performed; 380 samples were taken for the chemical analysis.

1.1.3.Hydrobiological sampling Phytoplankton Phytoplankton sampling was carried out with the help of bathometers of 3 and 10 l volume in day light at the depth to 1 m in the surface layer; at the depth more than 1 m – layer wise at the surface and near the bottom. Samples were fixed with the Watermell’s solution (Fedorov, 1979). A sample was reduced to the volume of 20-40 ml by the method of sedimentation, due to the sediment density. A total of 64 samples were collected. Zooplankton Zooplankton sampling was carried out by straining 200 l of water from the surface; at depths more than 1 m it was realized by the vertical trawling from bottom to surface with the help of a small Juday net (diameter of the inlet – 18 cm and gauze No. 73). Fixation was done with the neutralized formalin being added to a sample up to the concentration of 4 %. A total of 50 zooplankton samples were collected. Composition and volume of samples collected from the northeastern Sakhalin bays in September 2002 are reflected in Table 1.2.

Table 1.2 Composition and numbers of collected and processed materials from the bays of northeastern Sakhalin in September 2002 Name Sample numbers by the bays Piltun Chaivo Nyisky Nabil Lunsky Temperature 11 12 16 14 11 Salinity 11 12 16 14 11 pH 11 12 16 14 11 Dissolved oxygen 11 12 16 14 11 Biogenic matters 11 12 16 14 11 PHC concentration in water 11 12 16 14 11 Suspended matters 11 12 16 14 11 Chlorophyll а 11 12 16 14 11 Total content of PHC in BS 13 11 14 11 11 Phytoplankton 11 12 16 14 11 Zooplankton 11 9 12 9 9

1.2. Methods of laboratory studies

1.2.1. Chemical analysis of water samples Dissolved oxygen In order to determine a mass concentration of dissolved oxygen, a titrimetric method based on its reaction with the hydroxide of manganese (II) in the alkaline environment was used (RD 52.10.243-92, RD 52.24.419-95, PND F 14.1:2.101-97). The latter quantitatively couples the oxygen turning to the manganese compound (IV). When acidulating a sample over a surplus of 14 the potassium iodide, an iodine is formed which quantity is equivalent to the content of dissolved oxygen and determined by the titration of the thiosulfate sodium solution. A sensitivity of the method is 0.15 mkg/dm3. In the range of dissolved oxygen concentrations from 0.15 mg/dm3 to the saturation, the method's error does not exceed 3.4 %. Biogenic matters - A method for nitrite determination (N-NO2 ) was based on the diazotization of nitrites, occurring in water, with the sulfanilic acid under the further interaction of the formed diazocompound with a-naphthylamine, causing the appearance of the red azopaint (RD 52.10.243-92). Determination was conducted under the wave 543 nm long. A sensitivity of the method is 0.5 mkg/dm3; the error in the range of nitrite nitrogen concentrations from 0.5 to 2.5 mkg/dm3 does not exceed 18.02 %. - In order to determine nitrates (N-NO3 ), a method of nitrate reduction up to nitrite while passing through the copper-plated small-crystalline cadmium was used. After passing the sea water through a reducer, a sum of nitrates and nitrites was determined (with the Greess-Ilosway's reagent (RD 52.10.243-92). The nitrate concentration was calculated based on the known content of nitrites in a sample. The minimum determined concentration is 5.0 mkg/dm3; the error in the range of nitrate nitrogen concentrations from 5.0 to 25.0 mkg/dm3 is 7.39 %. 3- In order to determine orthophosphates (Р-РО4 ), a calorimetric method based on the formation of molybdenum heteropolysine (method of Morphy-Raily) was used. Phosphorus, as the orthophosphate, reacts with the ammonium molybdate in the presence of sulphuric acid and antimonialtartrate potassium. The formed complex of phosphomolybdic heteropolyacid and three-valent antimony was reduced by the ascorbic acid, and the optic density of the blue painted compound was measured under the wavelength of 750 nm (RD 52.10.243-92, RD 52.24.382-95). A sensitivity of the method is 5.0 mkg/dm3; the error in the range of concentrations from 5.0 to 100.0 mkg/dm3 is 4.6 %. A method for silicon content determination in water is based on the calorimetric determination of the reduced silicomolybdic heteropolyacid (RD 52.10.243-92) under 810 nm. A yellow silicomolybdic complex was reduced up to the blue silicomolybdic complex by the ascorbic acid. A sensitivity of the method is 10 mkg/dm3; the error in the range of silicon concentrations from 10.0 to 200.0 mkg/dm3 is 5.8 %, from 200.0 to 1000 mkg/dm3 – 4.6 %, from 1000 to 2000 mkg/dm3 - 5.8 %. In order to measure the optic density of the examined solutions when determining biogenic elements, a photoelectric calorimeter CFK-3 was used. Composition and a total number of studies for the content of biogenic matters in water samples from the northeastern Sakhalin bays are shown in Table 1.3. A total of 256 determinations on 4 ingredients have been performed.

Table 1.3 Composition and numbers of studies of the biogenic matters in water samples from the northeastern Sakhalin bays in 2002 Name Numbers of studies in bays Piltun Chaivo Nyisky Nabil Lunsky Phosphorus 11 12 16 14 11 (orthophosphates) Silicon 11 12 16 14 11 Nitrite nitrogen 11 12 16 14 11 Nitrate nitrogen 11 12 16 14 11

15 Mass concentration of petroleum products A measurement of mass concentration of petroleum hydrocarbons (PHC) in water was conducted by the fluorimetric method on the fluid analyzer “Fluorate-02-M” (PND F 14.1:2:4.128-98). A work of the instrument is based on measuring a signal of the petroleum product fluorescence in the hexane solution in conditional instrumental units with the further mathematical processing and displaying the results on the indicator as a concentration of petroleum products in the hexane extract. A sensitivity of the method is 0.005 mg/dm3, error not less than 65 %. Chlorophyll-а A content of chlorophyll a was determined by the spectrophotometric method according to the GOST 17.1.04.02-90. A method is based on a spectrophotometry of the pigment extract before and after its acidulating by the solution of hydrochloric acid. Calculations of the chlorophyll a concentration are based on the known specific spectrum indices of the light absorption by the chlorophyll a and basic components preventing the analysis. A sensitivity of the method is 0.02 mkg/dm3; the error for chlorophyll a concentrations from 0.2 to 0.7 mkg/dm3 is 20 %, higher than 0.7 mkg/dm3 – 10.0 %. Suspended matters Suspended matters were determined by the gravimetric method, and their definition was based on their distinguishing from a sample by means of the water filtration through a prepared filter and weighing the filter cake after its drying at the temperature 105 °С until the constant mass (RD 52.24.468-95). The minimum determined concentration is 2.0 mg/dm3; the error of the method for concentration of suspended matters from 2.0 to 10.0 mg/dm3 is 1 %, from 10.0 to 50.0 mg/dm3 –2 %, over 50.0 mg/dm3 – 5 %.

1.2.2. Quality control of hydrochemical studies In order to provide for a quality control of the conducted studies, some conditions have been carried out (GOST 17.1.5.05-85, RD 52.24.509-96, RD 52.24.268-86): • applying the means of control (state standard patterns – GSO, certified mixtures); • using devices of measurement, checked and calibrated directly before a chemical analysis with the use of GSO; • choosing the certified methods to analyze indices of the water composition according to the region of accrediting a chemical-analytical laboratory; • collecting the representative samples; • analyzing the blank field samples and blank laboratory samples (3 samples for a series of 10- 15 samples); • performing the control for measurement errors on the reproducibility of results of the measurements in the iterated work samples, and by the method of the standard addition to the work samples. Composition and a total number of hydrochemical analyses in water samples from the northeastern Sakhalin bays are shown in Table 1.2.

1.2.3. Determination of a total content of petroleum hydrocarbons in bottom sediments Samples were prepared for analysis according to STP 18.54-2001. The analysis was carried out by the method of a high-effective gas-fluid chromatography according to STP 18.48- 2001 (modified method EPA#8015B USA). The patterns were presented frozen according to the methodical demands made for this type of analysis. Extraction of patterns and purification of extracts The pattern of bottom sediments was defrosted before the beginning of analysis; some part was weighed and being wet put into the Erlenmeyer bottle. Then it was mixed with the equal size of the dehydrated natrium sulphate and crushed to powder with the help of a palette knife. Then the ersatz standard (2.22 mkg n-C24 D50) was introduced into the sample, added 30 ml of 16 hexane and thoroughly mixed with a palette knife. The Erlenmeyer bottle was put into the ultrasonic bath and extracted for 12 minutes. The liquid was decanted, and the extraction procedure was repeated, and extracts were united. The extracts were dried with the help of natrium sulphate, evaporated on the rotor evaporator to the volume of 1 ml and placed on the column filled with 4 g of activated alumina (activity 1 by Brockman). A fraction containing hydrocarbons was eluated by 20 ml of hexane. The purified extract was concentrated to 1 ml and placed into microampoule. To determine the outcome of ersatz standard, a recovery standard (5.25 mkg of 9,10-dibromoanthracene) was introduced directly before the instrumental analysis. Instrumental analysis The analysis was made on the chromatographs Carlo Erba Mega 5300 at the following conditions: Type of injector on column Type of detector PID Type of column Ultra-1 (HP-1) Length of column 30 m Diameter of column 0.32 mm Thickness of a phase film 0.17 mk Initial temperature of column 60 0С Initial time of delay 2 min. Rate of heating 30 0С/min Final temperature 300 0С Temperature of detector 300 0С Temperature of injector 60 0С Introduced volume 1 mkl Rates of gas flows: air 320 ml/min hydrogen 40 ml/min helium 2 ml/min A calibration test of the instrument was made using the standard solutions of heavy petroleum, close to the analyzed patterns by composition, and also using the standard solutions of n-alcanes of С10-С36 composition. A linearity of instrument was proved to be true by calibration for 5 points in the petroleum concentration interval of 4-100 mkg/ml. TRPH Standard SFL-601, lot. № L0435 of ULTRA Scientific production, Canada was used as a standard solution of n-alcanes. After each analytical series the calibration was proved to be true by the analysis of a standard solution of mean concentration. The received chromatograms were treated by the computer method using the applied programs of MultiChrom, version 5.4.

Computation of results A total content of petroleum hydrocarbons (C mkg/g) was computed based on the sum signal of hydrocarbons excreted by a chromatograph system, in the interval of time retentivity from n-C10 to n-C36 by the equation:

C mkg/g = ( ATPH - As - AR)(mS) / (AS) (M) (RRFTPH) where: ATPH - total area of hydrocarbon peaks in the interval of time retentivity, AS - area of the ersatz standard peak, AR - area of the internal standard peak, mS - quantity of ersatz standard, mkg, RRFTPH - relative factor of response for total petroleum hydrocarbons, M - weight of pattern (g).

RRFTPH was computed by analyzing the calibration solutions of petroleum: 17

RRFTPH = (ATPH - AS - AR) (CS) / (AS ) (CTPH ) where: CTPH - total petroleum concentration in a calibration standard, CS - ersatz concentration.

Analysis accuracy The analysis accuracy was determined by a series of 8 control patterns of bottom sediments containing 10 mkg/g of heavy petroleum. An average percentage of the petroleum extraction was 95 % under the standard deviation of the mean extraction 10 %. Detection limit of the method The limit of detection estimated statistically with the probability of 99 % by a series of repeated analyses of blank samples was 0.5 mkg/g for petroleum products in bottom sediments. The above limits of detection were tested during the analysis of a prepared control pattern series.

1.2.4. Quality control of determination of the petroleum hydrocarbon contents in bottom sediments The delivered samples were analyzed by series. Each series included 8-13 patterns, one of which was analyzed twice (duplicate), a control pattern prepared in laboratory, and a blank sample (procedural form). To prepare control patterns, the duplicates were used (sample DO, analyzed twice in the given series). A solution of petroleum (U.S. EPA-API Reference Bay Crude Oil WP681) of the known concentration in hexane was introduced in the hanging taken for analysis. A deuterative n-tetracosane n-C24D50 was used as the ersatz standard. 9,10- dibromoanthracene was used as the recovery standard. The petroleum-averaged content in a sample, received at the duplicate analysis was subtracted from the control pattern of petroleum hydrocarbon content, obtained by the results of analysis. Admissible criteria of the analysis quality: A content of petroleum products in a blank sample is lower than 20 mkg; n-alcanes С10 - С36 is lower than 1.0 mkg. A content of petroleum hydrocarbons being determined in the control pattern is from 65 to 120 % of the introduced number. Deviation of results during the duplicate analysis is not more than %±25 of a mean value plus a value of threshold of the method detectability, mkg/g. A range of meanings for the value of extraction of the ersatz standard is 60-120 %. Quality of instrumental data A sensitivity of instrument was determined once a day (or after the instrument adjustment) by the analysis of a standard solution, containing the mixture of n-alcanes from n- С10 to n-C36. An admissible criterion of quality is a correlation “signal:noise = 3:1” for 0.05 ng tetradecane in the injected volume. Chromatographic resolution was proved by the analysis of calibrating standards, carried out after each analytical series. A criterion of quality is a division of peaks of two standards n-C24Н50 and n-C24D50 along the base line. Instrument calibration linearity was determined by the analysis of 5 standard solutions of petroleum with concentrations from 4 to 100 mkg/ml. A criterion of quality – a tolerant standard deviation of the computed relative factor of response RRFTPH should be lower than 20 %. A working stability of the instrument was proved after the analysis of each series of patterns, analyzing a calibration petroleum solution of the mean concentration. A criterion of quality – differences in meanings of the value of relative factor of response RRFTPH computed after the analysis of each series of patterns should not exceed ± 15 %. An instrument purification test for the content of analyzed components was carried out after each analysis of the calibration standard solution by means of hexane injection. This gives the possibility to make certain that a signal of the analyzed components in the sample 18 was not evoked by a previous sample. An admissible criterion – a value of the introduced error due to the instrument background should not exceed 1 % of the mean value of determined concentrations. Under the discrepancy of quality criteria for the obtained values after conducting the analytical series, the causes of deviation are ascertained and the analysis of series is repeated. A total of 50 samples were analyzed for the content of petroleum hydrocarbons in bottom sediments from the northeastern Sakhalin bays.

1.2.5. Processing the hydrobiological samples

Phytoplankton Materials were processed with the help of the light microscope “LOMO-15-2”. A total of 64 phytoplankton samples were analyzed. Some keys were used to identify species (Konovalova et al., 1989; Konovalova, 1998; Cupp, 1993; Tomas, 1996, and others). Each sample was processed in two chambers: nannoplankton in the Nojott’s chamber (0.055 ml volume), microplankton and rare species in the “Penal” chamber (1 ml volume). Biomass was determined comparing the microphyte cells to the definite geometric figures (Koltsova, 1970; Makarova, Pichkily, 1970). The dominating species were considered those which abundance was not less than 20 % of the total microalgae abundance. Zooplankton Samples were processed by the count-weight method (Instruction…, 1978; Recommendations…, 1984; Svirskaya, 1987). Organisms were counted in the Bogorov’s chamber in 5 cm3 of the sample volume, reduced to 50-200 cm3, after which total sample sediment was examined, and large organisms were counted. The samples were diluted if the number of the counted organisms was more than 1000 in a portion, or less than 100 were concentrated. If the waters were «poor» regarding to plankton, zooplankton organisms were counted in total throughout the sample. Weights of organisms were determined according to the Tables of mean weights and formulae of linear dependence «length-weight» (Ulomsky, 1952; Mordukhay-Boltovsky, 1954; Braginsky, 1957; Borutsky, 1960; Borutsky, Stepanova, Kos, 1991; Balushkina, Vinberg, 1979, 1979 а; Lubny-Gertsyk, 1959; Kun, 1975), under the absence of data – by the Chislenko nomographic charts (1968). All the calculations were made at 1 m3. Identification of zooplankton forms was realized by the key-books (Rylov, 1940, 1940 а, 1948; Borutsky, 1952; Brodsky, 1948, 1950; Manuylova, 1964; Kutikova, 1970; Chislenko, 1971; Key-book …, 1977; Key-book …V. 1, 1994; Key-book …V. 2, 1995; Smirnov, 1971, 1976) up to a species, if possible. A total of 50 zooplankton samples were analyzed. 19 2. PILTUN BAY

2.1. General physic-geographic characteristics of the Piltun Bay

The Piltun Bay is the largest lagoon of the northeastern Sakhalin coast. Like the majority of other lagoons, Piltun Bay is very stretched from south to the north (56 km) and located between 52° 51’and 53° 22‘N. Its greatest width (mouths of rivers Sabo and Kadylanyi) reaches 11-12 km. The bay extension is 57 km (with the Astokh Bay – about 71 km). The maximum width of the bay is about 12 km, area - 435 km2. The bay is separated from the sea by two plain spits. The southern spit, so-called Astokh spit, is short; its extension is about 15.4 km, width - 0.2-0.7 km. The sand hills 6-10 m high occur on the spit; hills' slopes are flat and grown with grass and small bushes. The extension of the northern spit, so-called Piltun spit, is about 56 km; its width changes from 0.3 km to 1.8 km, in the region of channel to 0.7-7.3 km in the northern part of the bay. The southern part (the narrowest) of the Piltun spit is sandy with small hills 5-12 m high, covered with grass and rare cedar creeping. Sandy hills 25-43 m high rise in the northern part (the widest) of the Piltun spit. They are covered with cedar shrubbery and sparse growth of trees. The lower places are swamped; a lot of lakes are located there. The largest lakes: Gniloye, Zerkalnoye, Karasevoye, Lebyazhye, and Utinoye have the extension of 0.5 to 1.8 km. The bay inlet (about 500 m wide and 6 m deep) divides the bay into two unequal parts: a small (extension about 15.5 km and width 400-800 m) and shallow Astokh Bay, and a proper Piltun Bay. The Piltun Bay is connected with a sea by a channel of about 12.3 km in extension. The width of channel is from 0.7 to 1 km, depths on the fairway 2.0-6.6 m, at the outlet into a sea to 19 m. The prevailing depth in the Piltun Bay is about 3 m. The exception is the fairway part, where the depths reach 4-6 m. The main fairway passes along the channel, turns to the north-west near Cape Argivo, and disappears rapidly on the line of Cape Kashkalebagsh. The depths in the Astokh Bay are 1-2 m and increase up to 3-5 m only close to the outlet into the sea (Ecological studies…, 2001). Southern and northern coasts of the Piltun Bay are plain, swamped in some places, and grown with grass and shrubs. The western coast in the central part of the bay forms a terrace 15-30 m high, covered with creep brushwood and sparse growth of trees. A forest reaches the shore only in the region of Cape of Verkhoturov and in the northeastern part of the bay. The sites of high coast are interrupted by the low swamped areas in the river mouths. The eastern coast in the southern part of Piltun spit is low-lying, mainly, sandy, swamped in some places. In the widest part of the northern spit the shore presents a high (to 7-20 m) terrace, ended toward the bay mainly like a swamped low shore. The northeastern coast of the bay presents the swamped peatbogs. The following rivers flow into the bay: Sabo, Erri, Kadylanyi, Mukhto, Poromay, and Piltun; all of them are of tundra origin (Table 2.1.1). All Sakhalin rivers are related to the mixed type of feeding with a snow domination. The exception are rivers from the North-East Plain, where a ground feeding, constituting more than 50 %, prevails in the annual volume of run-off; this is greatly caused by the existance of wide bog tracts. Occurrence of the individual types of feeding changes during a year: a role of water melted from snow increases in spring, rain-water prevails in summer and autumn, and subterranean waters serve as a single source of river feeding in winter.

20 Table 2.1.1 Characteristics of the Piltun Bay rivers’ run-off River Mean annual A volume of run-off A volume of run-off during a discharge (m3/sec) during a flood flood in percentage of the (million m3) annual (%) Erri 0.25 2.8 25 Kadylanyi 4.50 54.5 31 Piltun 7.82 75.3 30

A root shore of the bay is sandy; it makes up flood-lands of the above rivers interchanging with ridges of low sandy hills covered with the undersized tundra forest. The major part of this forest is burnt at the site from the mouth of Poromay River to the mouth of Kadylanyi River. During the ebb, a coastal line of lagoon (up to 10 m wide) is being dried; an area of about 1 km is being dried near the mouth of Kadylanyi River (Labay et al., 1999). A considered region is located within the northeastern Sakhalin shelf and exposed to the influence of monsoon from the temperate latitudes. A seasonal change in predominant wind flows and significant differences between individual meteorological elements in the annual run is a distinctive climate peculiarity. The southeastern and southern winds’ prevailing is common for the period of summer monsoon. In summer the wind velocities are minimal, a recurrence of calms and weak winds in this period constitutes 40-50 %, storms are very rare. Since September, due to the beginning of reformation of the atmospheric processes, the recurrence of winds of the northern rhumbs increases: from the second half of October they appeared to be predominant, a transition to the winter monsoon takes place. As its consequence, a roughness of southeastern and southern directions with waves of 1- 1.5 m prevails in summer. The recurrence of calms and weak seaway in this period is high and reaches 30-45 %. In September a stable character of seaway is being disturbed, the prevailing heights of waves increase, reaching 2-2.5 m. Since October, with starting the formation of the winter monsoon, the roughness of northern rhumbs with waves 2-3 m high appears to be dominant. The greatest number of storms occurs in the autumn-winter period. Tidal fluctuations of a sea level affect greatly the formation of the lagoon hydrodynamics regime. In the study region the tidal fluctuations have a daily character, that is, one high and one low tide are being observed during 24 hours. A mean estimate of the daily tide at the inlet of the Piltun Bay makes up about 1.0 m, the maximum estimate 2.3 m. During the tidal waves penetration into the narrow channel, as a rule, the decrease in their amplitudes and increase in their phases take place due to diffraction and increase in the influence of bottom and lateral friction. The tidal wave penetration into the lagoon is accompanied with the rise of strong tidal streamline currents. These currents reach the maximum values in the channel, directly at the bay outlet. By the data of measurements, their mean values constitute 0.7-0.8 m/sec, and maximum values exceed 1.8 m/sec. The active dynamic processes in the strait cause a constant change in position of the Piltun Bay outlet. The shifting is stably oriented for the south; its mean velocity is the greatest for all the bays from northeastern Sakhalin – approximately 35 m/year.

2.2. Hydrology and hydrochemistry of the Piltun Bay

2.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data The archive data on the Piltun Bay are presented by the results of monitoring studies in lagoons and coastal zone of the northeastern Sakhalin in 1995-1996 (Samatov et al., 1997), and materials collected during the joint scientific expedition of SakhNIRO – “Ecological Company of Sakhalin” in June-July 1999 (Labay et al., 1999; Ecological studies…, 2001). The data on hydrologo-hydrochemical regime practically are absent in the literary. 21 Surveys on the bay hydrochemical regime in August 1996 included only the analysis of samples for biogenic element contents. A total of 6 stations embracing the southwestern coast, southern extremity of Astokh Bay and a region of Peschanoye Lake were performed. Water sampling and determining the content of biogenic elements were carried out according to the certified methods (RD 52.10.243-92) in the Laboratory of Biological Oceanography, SakhNIRO. In June-July 1999, during the complex expedition, a series of hydrochemical samples and those of bottom sediments (BS) have been collected; it allowed a rather detail description of state of the Piltun Bay ecosystem. In order to determine hydrochemical characteristics, suspended matters, and chlorophyll-a, a total of 11 stations were performed, one of which was a daily station. A temperature regime of the Piltun Bay is determined by the seawater flow through the channel, radiation warming and in-shore run-off. In the summer period, the lowest water temperatures have been recorded in the deep-water near-strait part of the bay, where the thermal regime is determined by the cold seawater influence. During the survey, a water temperature in the region was 10-12 °С, on the rest area the temperature varied insignificantly, constituting 16- 18 °С in the surface layer, and 15-17 °С in the near-bottom layer. The increase in temperature up to 19-22 °С was recorded only in shallow zones near the bay coast. A vertical structure of the temperature field was characterized almost by the full homogeneity in shallow zones and temperature lowering from the surface to the bottom (1-2 °С lesser) on the major part of the area. Only in the near-strait part a temperature contrast between the surface and near-bottom layers was more expressed and constituted 2-4 °С. A salinity regime of the bay water is determined by the joint influence of sea tides and river run-off. The water with more than 20 ‰ of salinity in the surface layer was recorded only in the channel, near the bottom the penetration of salt waters was observed up to 3 km to the west of Cape Argivo. When moving away from the channel, salinity is lowering rapidly; on the major part of the area north of Cape Kashkalegbagsh its value does not exceed 2-5 ‰, and in the western part of the bay near the coast - 0-2 ‰. A vertical salinity distribution on the major area of the bay is practically homogeneous: differences do not exceed 1-2 ‰. Only directly in the channel the vertical salinity gradients increase up to 2-4 ‰. The analysis of the daily temperature and salinity run shows that under the tide the seawaters are being distributed, first, over the bottom of the lagoon deep part. They underlay a river run-off and, being impossible to move farther to the north, force out fresh river waters to the shallow zone, where their active confusion and transformation occur later on. During the ebb, fresh river waters are being distributed over the major part of the lagoon and occupy a predominant position on the shallow area (Ecological studies…, 2002). pH values of the bay water varied within 5.4 – 7.1. The low pH values were associated with the inflow of acidic waters with a terrigenous run-off. The content of dissolved oxygen varied within 7.6 – 11.1 mg/dm3 that proved a good saturation of surface waters with oxygen. In the shallow zones near the southeastern bay coast, concentrations of oxygen constituted 5.7 – 7.2 mg/dm3. Suspended matters in the bay water ranged from 4.0 to 21.0 mg/dm3 in the central part of the bay in the region of mouths of rivers Erri, Khalchkova, and Sabo. The maximum concentrations of suspended matters (102.0 – 105.0 mg/dm3) were recorded at the outlet of Liman Lake and in the mouth of Sabo River. The estimates of biochemical oxygen demand on the transect in the central part of the bay constituted 2.79 – 4.10 mg/dm3, at the daily station – 2.26 – 6.21 mg/dm3, averaged 4.93 mg/dm3. The values of permanganate oxidation at two 3 stations in the central part of the bay constituted 9.6 and 12.8 mgО2/dm . At the daily station in 3 3 the channel, values varied from 7.62 to 14.85 mgО2/dm , averaged 12.93 mgО2/dm . A ratio between the BOD5 and permanganate oxidation values practically at all stations was significantly lesser than 1; this proves the active inflow of humus acids with the terrigenous run-off. Concentrations of biogenic matters in the bay water in 1996 were rather high and varied as follows: nitrates from 0.80 to 11.20 mkg/dm3; nitrites from 3.44 to 10.81 mkg/dm3; ammonium ions from 0.00 to 104.39 mkg/dm3; silicon from 449.0 to 6820.00 mkg/dm3. A 22 content of general phosphorus on the major part of the area varied within 15.0 - 89.2 mkg/dm3, only at the outlet of Sabo River a concentration of 215.0 mkg/dm3 was recorded; phosphates constituted from 44.0 to 68.0 mkg/dm3. In 1999, concentrations of inorganic phosphorus in the bay varied from 1.5 to 26.0 mkg/dm3, organic phosphorus from 3.0 to 82.0 mkg/dm3. The domination of organic phosphorus is associated with the great influence of the continental run-off. At the daily station in the strait a content of general phosphorus varied from 32.0 to 72.3 mkg/dm3, averaged 65.8 mkg/dm3. The mean concentration of inorganic phosphorus was 39.5 mkg/dm3, organic phosphorus 21.2 mkg/dm3. The domination of inorganic phosphorus is associated with the influence of seawaters. The increase in silicon concentration was observed with moving away from the channel and fairway. In the near-strait part, where the influence of seawaters is great, silicon concentrations at the surface varied, mainly, within 497.0 – 2995.0 mkg/dm3. Along the coast at the mouth sites of rivers with the increase in the terrigenous run-off influence, silicon contents increased to 3626.0 - 7700.0 mkg/dm3. Nitrite contents during the survey varied from 0.0 to 2.24 mkg/dm3 at all stations. Nitrates were not found in water samples; this indicated practically a full exhaustion of nitrogen supply for the photosynthesis in conditions of the mass phytoplankton development. Concentrations of chlorophyll-a at the daily station in the channel were 2.58 – 12.18 mkg/dm3, averaged 5.62 mkg/dm3. In the near-strait part of the bay a chlorophyll-a content in water was 6.18-6.88 mkg/l; with moving away from the channel, concentrations were lowering to 1.0 - 4.4. mkg/dm3.

2.2.2. Results of hydrologo-hydrochemical researches in 2002 Results of hydrologo-hydrochemical studies of the Piltun Bay samples in September 2002 are given in Appendix 2.2.1. Some statistic characteristics of the determined parameters are shown in Table 2.2.1. Since the depth of Piltun Bay at all stations did not exceed 0.9 m, sampling was conducted only from surface horizons. Due to the shallow waters of the bay, the mean water temperature was rather high, compared to other bays of the northeastern Sakhalin, and constituted 14.8ºС during sampling. The minimum water temperature was observed at station 6 located between the mouths of rivers Piltun and Paromay (11.4 °С), maximum at station 5 (17.8 °С) (Table 2.2.1, Appendix 2.2.1). The minimum estimates of salinity (0.1-0.3 ‰) were recorded at stations 6 and 7; this is also associated with the influence of fresh waters of rivers Piltun and Paromay. The maximum values (11.8, 13.0, 13.5 ‰) were recorded at stations located closely to the bay inlet, where the influence of seawaters was the strongest (stations 4, 10, 9, respectively).

Table 2.2.1 Some statistic characteristics of hydrochemical parameters in Piltun Bay in September 2002 Ingredients Xav Xmax Xmin Depth, m 0.7 0.9 0.3 Temperature, °С 14.8 17.8 11.4 Salinity, ‰ 6.7 13.5 0.1 pH value 8.17 9.04 6.92 Dissolved oxygen, mg/dm3 9.78 10.30 8.93 Nitrogen nitrite, mkg/dm3 < 0.5 1.1 < 0.5 Nitrogen nitrate, mkg/dm3 < 5.0 11.0 < 5.0 Phosphorus (orthophosphates), mkg/dm3 43.4 110.2 17.6 Silicon, mkg/dm3 857.3 1953.7 264.0 Mass concentration of petroleum hydrocarbons, mg/dm3 < 0.005 < 0.005 < 0.005 Suspended matters, mg/dm3 14.70 39.27 2.50 Chlorophyll-а, mkg/dm3 3.85 8.02 1.02 23 On the whole, a concentration of dissolved oxygen in water samples from the Piltun Bay was rather high, despite the high temperatures, constituting 9.78 mg/dm3, on average. Stations 6, 9, 11 located in the southern and southwestern parts of the bay were distinguished among others. There the concentrations of dissolved oxygen were minimal and significantly lower than average (8.93, 9.09, 9.22 mg/dm3, respectively), evidently, due to the discharge for oxidizing humus matters being washed from the swamped areas. This supposition is proved by the comparatively low pH values of water samples at these stations (7.27, 7.98, 8.13). The maximum concentrations of dissolved oxygen were recorded at stations 1 and 5 (10.30 mg/dm3). Concentrations of nitrite and nitrate nitrogen were minimal in major cases and occurred below a threshold detectability of the method (0.5 and 5.0 mkg/dm3, respectively) or were equal to it. Only at several stations from the southern and southwestern parts of the bay (stations 3, 7, 9, 10), nitrites were found in concentrations from 0.6 to 1.1 mkg/dm3, and only at two stations (6, 7) nitrates were found, concentrations of which in water samples were 5.0 and 11.0 mkg/dm3, respectively. Phosphorus (orthophosphates) and silicon distribution patterns over the bay area were rather uneven. A content of phosphorus varied from 17.6 mkg/dm3 (st. 8) to 110.2 mkg/dm3 (st. 1). The mean estimate of phosphorus concentration in Piltun Bay was 43.4 mkg/dm3. Silicon contents in water samples varied from 264.0 to 1953.7 mkg/dm3 (st. 3 and 7, respectively). The mean estimate of silicon concentration was 857.3 mkg/dm3. Examinations of water samples from the Piltun Bay for petroleum products did not give positive results; all estimates occurred below a threshold detectability of the method (< 0.005 mg/dm3). Distribution patterns of suspended matters in water samples over the study area were extremely heterogeneous and varied from 2.50 to 39.27 mg/dm3 (stations 6 and 9, respectively). The averaged sample showed a presence of suspended matters in the concentration of 14.70 mg/dm3. The mean chlorophyll-a concentration was 3.85 mkg/dm3, varying widely from 1.02 to 8.02 mkg/dm3 (stations 6 and 4). The maximum contents of chlorophyll-a were recorded at stations (2, 4, 9, 10), located in a zone of influence of seawaters (salinity from 8.8 to 13.5 ‰), minimum at stations (1, 6, 7), undergone by the influence of river run-off (salinity from 0.1 to 2.8 ‰). Thus, by the results of studies we may conclude that sea and river waters and terrigenous run-off influence upon the distribution of the main determined hydrochemical parameters over the Piltun Bay area. Seawaters affect the northern part of the bay and stations located close to the channel joining the bay and the sea. River waters and terrigenous run-off affect the southern and southwestern parts of the bay and coastal stations. Estimates of concentrations of all the determined ingredients were within the standard in accordance with the demands to water composition and characteristics of water objects used for fisheries aims (List of fisheries standards, 1999); often the concentrations of determined parameters were below a threshold detectability of the method.

2.3. Particle-size composition of bottom sediments in the Piltun Bay

In 1999, a particle-size composition of bottom sediments was studied at 43 stations. The analysis of a particle-size composition of bottom sediments was carried out by the sieve and aerometric methods according to the GOST 12536-79 in the laboratory of Far East Marine Engineer-Geologic Expedition (DMIGE, Yuzhno-Sakhalinsk). All types of grounds occurred in the bay: from the graveled sand to loamy silts. The maximum estimates of coarse-grained fractions of sediments (gravel and coarse-sandy) were observed in the mouth zones of rivers, where the ground was represented by graveled sand. The higher numbers of aleuro-pelite fractions of ground were recorded in the central and southern parts of the bay. A rather great volume of studies on the particle-size composition of the Piltun 24 Bay bottom sediments let us to make diagrams of spatial distribution of the main particle-size fractions of grounds and to construct a map-scheme of distribution patterns for the main types of grounds (Fig. 2.3.1).

53.3353° 20' р. Эрри

7.00 7 6.50 6 5.50 5 4.50 р. Сабо 4 3.50 3 2.50 2 1.50 р. Кадыланьи 53.0053° 00' 1 0.50

р. Паромай

р. Пильтун

143.08143° 05' 143.25143° 15'

Fig. 2.3.1. Distribution of the main types of grounds in the Piltun Bay 1. Loamy silts 2. Loams 3. Fine sand 4. Medium sand 5. Coarse sand 6. Gravel small-sized 7. Gravel medium-sized 25

2.4. Content of pollutants in the Piltun Bay

2.4.1. Content of pollutants in bottom sediments by the archive and literary data During the August 1996 researches, the tasks of estimation of the Piltun Bay pollution level have been solved. A character of anthropogenic pressure in the northeastern Sakhalin bays has determined the choice of toxicants for examination. This group included petroleum hydrocarbons (PHC), phenols, metals, chlororganic pesticides (COP), and polychlorinated biphenyls (PCB). Based on the collected data, the levels of contents of toxic matters in bottom sediments, fish tissues, and Zostera were analyzed. Both a rod grab was used for ground sampling and the ground was collected directly in the before-treated ware. In order to conduct an instrumental analysis, samples were stored deeply frozen (-18 ºС). In 1995, the analysis of ground samples for the content of PHC was carried out by the chromatic-mass-spectrometric method in the Auke Bay Laboratory (Djuna, Alaska, USA). Chlororganic pesticides were determined by the chromatograph method there too (J. Short et all Standard…). In 1996, the contents of polyaromatic hydrocarbons (PAHC), non-volatile hydrocarbons, and resinous matters were analyzed in Azov Research Institute of Fisheries (AzNIIRKH, Rostov-on-Don) by the method of thin-layer chromatography. Pesticides in the same year were analyzed by the method of gas-chromatography (RD 15-258-94 – RD 15-267- 94); the analysis of heavy metals and arsenic was carried out by the roentgen fluorescent method (RFA) (RD 15-268-94 – RD 15-270-94, RD 15-273-94 - RD 15-275-94) and that of atomic- absorption spectrophotometry (AAS) (RD 15-226-91, RD 15-228-91, RD 15-229-91, RD 15- 231-91, RD 15-232-91) in the AzNIIRKH laboratory too. In 1995, microelements in bottom sediments were determined by the above atomic- absorption methods, phenols by the spectrophotometric method (Methodical instructions…, 1979) in the Laboratory of Applied Ecology and Toxicology, TINRO (Vladivostok). In 1999, concentrations of PHC and COP in bottom sediments were studied at 5 stations, contents of metals in bottom sediments at 37 stations, and contents of metals in Zostera at 3 stations. Fish tissues (muscles and liver) were examined for the content of metals in the region of channel and in the mouth of Sabo River. In addition, at 43 stations the bottom sediments were examined for the content of organic carbon. Contents of PHC and COP in bottom sediments and hydrobiont tissues were determined by the method of gas chromatography in the laboratory NPO “Ocean” (Vladivostok) by the standard methods (Ravinsky et al., 1999). The metal analysis was carried out by the AAS method according to standard methods of determination (Methodical recommendations…, 1987). Organic carbon was determined by the method of dry burning under the temperature 440 ºС (GOST 23740-79). Studies of the bay bottom sediments for the content of petroleum hydrocarbons (PHC) had shown that in 1996 the mouth of Paromay River was the most polluted (110.0 – 400.0 mkg/g). A proportion of resinous matters was about 30 %. At the rest sites the concentrations of resinous matters were insignificant (8.0 – 70.0 mkg/g). The range of non-volatile hydrocarbons was within 50.0 – 400.0 mkg/g. On the whole, a great range of fluctuations for the total content of components was observed (from 60.0 to 510.0 mkg/g). Contents of polyaromatic hydrocarbons in bottom sediments varied from 0.09 to 0.25 mkg/g, averaged 0.16 mkg/g. In 1999, a content of petroleum products in the Piltun Bay bottom sediments was determined, mainly, in its southern part. Concentrations of petroleum products varied from 0.0 to 1.7 mkg/g, averaged 0.41 mkg/g. The maximum content of petroleum products (1.7 mkg/g) was recorded along the coast in the southern part of the bay. At the rest stations the petroleum product concentrations in bottom sediments had a trace character. It is difficult to estimate a distribution of petroleum products in the bay bottom sediments due to the limitation of observing stations. Nevertheless, the higher concentrations of petroleum products were mainly observed in the stagnant zones. In 1999, a content of organic carbon varied from 0.0 to 5.3 %. Concentrations of organic 26 carbon in bottom sediments varied within 1.5-2.5 % in the central and southern parts of the bay, and they lowered up to 0-1 % along the coast in the northern part of the bay and in the channel. The maximum concentration (5.3 %) was recorded in silty sediments in the central part of the bay. A character of distribution of the organic carbon coincided with the distribution of thin (<0.1 mm) fractions of bottom sediments. By the data of chromatic-mass-spectrometry, the mean content of chlorinated phenols in the Piltun Bay bottom sediments in 1996 was 12.33 ng/g and varied from the trace estimates (n/o) to 38.00 ng/g. The maximum concentrations of chlorinated phenols were observed in the southern (codened) part of the bay. Trichlorophenols prevailed among chlorophenols. Their proportion was 67.7 % of the total number of chlorophenols; tetrachlorophenol and monochlorophenols followed them. In 1996, chlororganic pesticides (COP) in bottom sediments were found in the Piltun Bay only at one station (in the south of the codened part); a sum content in this place was 0.17 ng/g. Of HCCH (hexachlorocyclohexane) isomers, only γ-HCCH (0.04 ng/g of the dry weight) was found there. Metabolites of DDT (dichlordiphenyltrichloroethane) were represented more widely. о, p-DDE, p,p-DDE, o,p-DDD were found, their total number constituted 0.13 ng/g. In 1999, the presence of COP was found in grounds of 2 stations. Two of 5 compounds being determined were found on the study area. DDT was found in one sample, its metabolite DDD – in two samples. The mean sum content of pesticides in the Piltun Bay bottom sediments was 0.04 ± 0.06 ng/g. The maximum of summarized COP concentrations (0.14 ng/g) was found at the outlet of the channel.

In Table 2.4.1 some statistic characteristics and a gross content of metals in the Piltun Bay bottom sediments are given by the results of studies in August 1996.

Table 2.4.1 A gross content of metals in the Piltun Bay bottom sediments in August 1996 (mkg/g of the dry weight, Аl and Fe - in %) n* Index Al, % Fe, % Mn Ba Zn Cr Ni Cu Co Pb As 6 Mean 4.0 0.71 118 592 16.6 127.3 38.5 17.2 2.95 15.2 4.80 St.dev. 1.3 0.39 86 96 11.8 112.5 6.7 1.0 1.38 4.2 0.68 Min 2.5 0.37 37 410 5.9 49.0 32.0 16.0 1.10 11.0 3.90 Max 5.7 1.28 275 660 35.0 350.0 48.0 18.0 4.30 21.0 5.90 *n – a number of stations

Statistic parameters of the content of mobile metal forms in the surface layer of the Piltun Bay bottom sediments in June-July 1999 are given in Table 2.4.2. According to correlation matrixes of the metal acid-dissolved forms, particle-size composition of bottom sediments, and depths for Piltun Bay (Ecological studies of the bays…, 2001), a significant positive relation of one with another occurred practically for all the elements, except for cadmium (coefficients of correlation 0.50-0.96). Correlation coefficients of metals with mercury were a little lower (0.38-0.53). For the majority of elements (except for cadmium, copper, and mercury) a significant positive relation with a depth was found. Concentrations of the major active forms of metals in bottom sediments showed a negative relation with sandy and gravel-pebble fractions. For fractions from 0.5 to 5.0 mm the noted relation with the major elements (except for cadmium, copper, and mercury) reached significant values (correlation coefficients from -0.34 to -0.49). Contents of major metals showed a high positive correlation with the content of fractions less than 0.1 mm in size (correlation coefficients 0.44-0.87, for mercury 0.37-0.68). The exceptions were cadmium, which relation with the fractional composition of grounds was not found, and lead, for the content of which a significant positive relation with fractions less than 0.01 mm was recorded.

27 Table 2.4.2. Statistic parameters of metal distribution (n=37, mkg/g of the dry weight, Al and Fe – in %) in the Piltun Bay bottom sediments in June-July 1999 Metal Xav σ Median Mode Min Max Al 2.6 2.0 2.0 2.0 3.0 12.5 Fe 4.8 3.9 3.6 1.4 2.5 15.3 Mn 38,2 36,4 24,0 10,0 1,3 225 Zn 15,3 13,8 8,5 8,0 2,0 52,0 Cr 14,6 13,1 9,5 4,0 2,0 46,3 Ni 13,5 14,3 7,5 1,0 0,4 51,0 Cu 4,44 2,30 4,00 2,00 1,30 11,3 V 11,6 9,36 15,00 20,00 0,00 30,0 Co 1,56 1,41 1,00 0,40 0,12 8,00 Pb 1,79 1,68 1,25 0,50 0,50 7,50 Cd 0,17 0,13 0,15 0,05 0,05 0,50 Hg 0,009 0,004 0,007 0,006 0,005 0,020

Thus, the obtained results of the correlation analysis proved the fact that contents of the metal acid-dissolved forms in bottom sediments were determined, mainly, by one factor – sorption abilities of bottom sediments. The affect of sorption peculiarities of grounds, to a less extent, determined the concentrations of metals-tracers of the anthropogenic impact: cadmium, mercury, lead.

2.4.2. Content of pollutants in biota On average, a level of accumulation of general carbons in the bay Zostera in August 1996 was 1.4 mg/100g of the wet weight, PHC– 0.001 mg/100 g. When analyzing Zostera for the COP and PCB contents, only one kind of pesticides (α- HCCH) was found; its concentration constituted 0.06 ng/n of the wet weight. The mean concentrations of metals in plants are presented in Table 2.4.3.

Table 2.4.3. Mean metal contents in Zostera of the Piltun Bay in August 1996, mkg/g of the wet weight Metal Concentration Zn 0.001 Cu 0.0004 Hg 0.000003 Pb 0.00004 Cd 0.00011 Cr 0.0014

There are not many data on the metal content in Zostera in June-July 1999. Surveys have been conducted at four stations, and results are given in Table 2.4.4. Contents of Zn, Cu and Pb in Zostera of Piltun Bay in 1999 were higher than those observed during the earlier surveys for this region (Krasavtsev et al., 1991; Samatov et al., 1997). Concentrations of Cd appeared to be within the earlier noted limits. 28

Table 2.4.4 Mean metal contents in Zostera of the Piltun Bay in June-July 1999, mkg/g of the dry weight Station Length, mm Object Fe Mn Cu Zn Pb Cd Ni r. Sabo 87,4±14,6 whole 2746 68,5 5,31 62,6 6,12 0,71 6,57 20 77.0±20,8 whole 5564 159 10,5 74,6 9,49 0,98 7,80 26 111±30,7 whole 1068 207 0,56 15,8 2,34 0,23 1,69 39 667±194 leaves 1487 207 5,10 43,5 7,06 1,77 5,66

By the results of surveys, HM contents in the Piltun Bay Zostera tissues were significantly higher in 1999 compared to those in 1996; this may be connected with differences in methods used for analysis (in 1996 a dry weight was analyzed, and in 1999 – a wet weight). Reducing the results to similar units of measure is impossible because of the absence of information on water content (humidity) in a wet weight. In addition, differences in time sampling play an essential part: in growing organisms (June) the higher concentrations of metals (especially zinc and copper) are always being marked. The results of study of the metal distribution in fish organs (Fig. 2.4.1, 2.4.2, 2.4.3) of the Piltun Bay showed the essential differences in the microelement composition of liver and muscle tissues of female and male flathead sculpin. Evidently, this reflects physiological and biochemical peculiarities of organs for different sexes. Species peculiarities in metal accumulation by fish tissues were also watched on the example of females of sculpin and flounder: flounders’ liver contained more Al, Zn, Mn, and Cd, compared to sculpins. The levels of Fe, Cu, Mn, Ni, and Cd accumulation were lower and Zn, Cr, and Co higher in flounders’ muscles. 29

1000

100 массы . сух

г

/ 10 печень мкг , мышцы 1

0.1 Концентрации 0.01 Al Fe Zn Cu Mn Cr Co Ni Cd Hg Металлы

Fig. 2.4.1. Metal concentrations in tissues of male flathead sculpin from Piltun Bay in June-July 1999 (logarithmic scale)

10000

1000

массы .

сух 100

г

/ печень 10 мкг , мышцы 1 0.1

Концетрации 0.01 Al Fe Zn Cu Mn Cr Co Ni Cd Hg Металлы

Fig. 2.4.2. Metal concentrations in tissues of female flathead sculpin from Piltun Bay in June-July 1999 (logarithmic scale) 1000

массы

. 100

сух печень г / 10 мышцы

мкг , 1

0.1

Концентрации 0.01 Al Fe Zn Cu Mn Cr Co Ni Cd Hg

Металлы

Fig. 2.4.3. Metal concentrations in tissues of the female banded flounder from Piltun Bay in June-July 1999 (logarithmic scale) 30

2.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 Results of analysis of the bottom sediment samples for the content of petroleum products in the Piltun Bay are given in Table 2.4.5. As one can see from the Table, the estimates of petroleum hydrocarbons (PHC) in the Piltun Bay bottom sediment are distributed very unevenly over the study area, and their concentrations in samples varied widely from 0.74 to 22.3 mkg/g. The maximum estimates were observed at stations 7, 11 (22.3, 18.6 mkg/g, respectively), minimum at stations 2, 10 (0.74, 1.09 mkg/g, respectively). The definite regularities for the petroleum products distribution in bottom sediments were not found, but we should note the higher level of PHC accumulation at stations exposed to the influence of terrigenous and river run-offs (rivers Paromay and Kadylanyi) (st. 7, 11), whereas at stations 2 and 10, being under the influence of seawaters (8.8-13.0 ‰), the accumulation of PHC in bottom sediments was minimal.

Table 2.4.5 A summarized concentration of petroleum products in samples of bottom sediments in 2002 and results of the analysis quality control № st. Concentration of Mean Extraction of ersatz standard,% petroleum products, divergence of mkg/g duplicates, % Mean Relative standard deviation Pi 1 7.36 23 75 35 Pi 2 0.74 Pi 3 1.78 Pi 4 5.66 Pi 5 5.62 Pi 6 5.42 Pi 7 22.3 Pi 8 11.6 Pi 9 4.66 Pi 10 1.09 Pi 11 18.6

The analysis of results of the quality control has shown that % of the duplicate divergence and % of the extraction of ersatz standard did not exceed the tolerance criteria of quality. Thus, by the archive data and results of studies of abiotic parameters, we can do the following conclusions. A hydrochemical regime of the bay is determined by the inflow of sea and river waters, and terrigenous run-off, and it is closely connected with the hydrodynamics regime of Piltun Bay. A particle-size composition of bottom sediments is presented by all types of grounds – from graveled sand to loamy silts. Coarse sediments are recorded near the river mouths, thin grounds in the central part of the bay. The occurrence of COP in Piltun Bay is explained by the external terrigenous sources of inflow. The maximum estimates of organic carbon were recorded in silty sediments of the central part of the bay. The content of metals in bottom sediments is not high; concentrations can be noted as background. The results of correlation analysis prove the fact that contents of the metal acid- dissolved forms in bottom sediments are determined, mainly, by one factor – sorption abilities of 31 bottom sediments. A basic source of the metal inflow is the thin suspended matters of terrigenous run-off. The higher lead content is common for metal concentrations in Zostera; this is caused by the high regional background. Sex differences were noted for metal distribution in fish organs. Rather high concentrations of zinc in fish tissues require the additional studies of migratory processes in order to find the sources of its inflow. Concentrations of petroleum products in bottom sediments had, mainly, a trace character (except for the 1996 surveys) and were predominantly of the natural origin. Their higher contents were recorded in the southern part of the bay near the mouth of Paromay and Kadylanyi rivers, where the occurrence of phenols was observed too. Rather significant differences between the results of the 1996 surveys and those of the following years can be caused, to some extent, by using a rough method of researches in 1996 (a thin-layer chromatography), and unfavorable ecological conditions during a sampling period.

2.5. Microbiological researches in the Piltun Bay

When studying a structure of the water microbe cenosis in the Piltun Bay in July 1999, a total of 2 water samples were collected (conditionally named stations 1, 2). Numbers of the following physiological groups of aerobic heterotrophic colony-forming microorganisms were determined in water: saprophyte heterotrophic bacteria, growing on RPA, marine heterotrophic organisms, developing under the different water salinity (environment of Yoshimitsu-Kimura); petroleum-oxidizing, phenol-resistant, and metal-resistant; proteolytic bacteria. A content of saprophyte heterotrophic bacteria in the examined water samples from the Piltun Bay stations in 1999 was 104 cell/ml. A number of marine heterotrophic bacteria adapted to the salinity gradient were 104 – 105 cell/ml in all samples. The mean number of phenol- resistant microorganisms was 104 cell/ml, a number of petroleum-oxidizing microorganisms ranged within 103 - 104 cell/ml (Table 2.5.1).

Table 2.5.1 Indices of numbers of the physiological groups from the aerobic saprotrophic microorganism community in seawater of the Piltun Bay studied stations, (cell/ml) Physiological groups of Numbers of microorganisms microorganisms st.1 st.2 Marine saprotrophic organisms 105 104 Heterotrophic organisms 104 104 Phenol destructors 104 104 Petroleum destructors 103 104

The number of proteolytic bacteria was determined only in one water sample, where the microorganisms from this group constituted 28.2% of the total numbers of heterotrophic organisms (Table 2.5.2). The indices of numbers of the metal-resistant microorganisms were rather high. They appeared to be in Cu-, Ni-, Pb-, Fe-resistant microorganisms, which higher numbers were recorded in all the studied bays of the northeastern Sakhalin, and explained by the geochemistry of this region and occurrence of Pacific ore belt.

32 Table 2.5.2 Relative numbers of some physiological groups from the aerobic saprotrophic microorganism community in seawater from the Piltun Bay stations (% of the total numbers of heterotrophs) Physiological groups of Numbers of microorganisms microorganisms st. 1 st. 2 Proteolytic 28.24 - Pb-resistant 24.4 97.3 Cu- resistant 13.7 36.8 Ni- resistant 33.6 65.8 Zn- resistant 0.76 23.7 Fe- resistant - 63.2

2.6. Phytoplankton of the Piltun Bay

2.6.1. Description of phytoplankton by the archive and literary data In 1999, a total of 14 phytoplankton samples were collected in the surface layer (0-50 cm) of the Piltun Bay during the joint expedition of SakhNIRO and ECS. In total, more than 280 species and intraspecific taxons belonging to 7 divisions have been found. Diatom algae made the main contribution to species diversity. Freshwater species prevailed (38 – 65 %), a proportion of marine species reached the maximum in the strait at the outlet from the bay into the sea (38 %). Four divisions: diatom, bluegreen, green, and cryptophyte algae played the main part in the phytoplankton biomass formation. Species indicating the eutrophication of the Piltun Bay waters dominated (by numbers) in the surface waters: in the freshened northern regions – a bluegreen alga Anabaena scheremetievii, in the bay center - Anabaenopsis hadsonii (bluegreen), Scenedesmus quadricauda (green), and Anabaena scheremetievii (bluegreen). Closer to the outlet from the bay to the sea, a brackish diatom Cylindrotheca closterium dominated. Based on the index of similarity, Shoener’s index, phytoplankton communities were distinguished. The community Cylindrotheca closterium was distinguished at the highest level of similarity in the southern part of the bay. The community Navicula directa formed in the mouths of rivers Sabo and Kadylanyi was distinguished at the lesser level of similarity. The community Podosira parvula + Melosira moniliformis was distinguished at the low level of similarity in waters of the central part of the bay and those washing the western shore in the narrowest part of the bay. In all communities diatoms had the greatest species diversity. A group of diatom algae also made the main contribution to the total (Labay et al., 1999).

2.6.2. Characteristic of phytoplankton in 2002 In September 2002, phytoplankton of the Piltun Bay area was formed by 8 divisions of microalgae; diatoms Bacillariophyta (123 species and intraspecific taxons) dominated among them by the number of species. The rest divisions were not abundant regarding to species representation: dinoflagellates (Dinophyta) – 14, green (Chlorophyta) – 14, bluegreen (Cyanophyta) – 10, cryptophytes (Cryptophyta) – 9, chrysophytes (Chrysophyta) – 4, euglenic (Euglenophyta) – 4, and rhaphidophytes (Rhaphidophyta) – 1. A total of 179 species and intraspecific taxons have been found. Among diatom algae, genera Navicula (20), Nitzschia (12), Achnanthes (8) were the most abundant by species (Appendix 1). Numbers of species at stations varied from 24 to 64. Diatoms were the most diverse. Cocconeis scutellum Ehr. (frequency 91 %), Nitzschia palea (Kutz.) W.Sm. (91 %), Ankistrodesmus convolutus Corda (91 %), Achnanthes lanceolata var. rostrata (Oestr.) Hust. (82 %), Navicula cryptocephala Kutz. (82 %) were the most frequent. The ecological characteristic is given for 22 species and intraspecific taxons (Appendix 1). Neritic species prevailed on the bay area (95 % of the total number of species with the known 33 ecological characteristic); pantalass species made up 5 %. A phytogeographic analysis was carried out for 30 species and intraspecific taxons with the known ecological belonging (Appendix 2.6.1). In the study region, 8 groups of species with the similar type of area were found; of them the following widely distributed species dominated: cosmopolites (30 %) and boreal species (26 %). Freshwater species (41 %) and fresh-brackish ones (27 %) played the main part in forming the main species composition. Marine species constituted 11 %, brackish and fresh- brackish by 9 %, and freshwater, perhaps, brackish-marine – 3 %. In the study region the estimates of quantitative indices ranged widely: biomass from 24,83 mg/m3 to 901,87 mg/m3, averaged 382,131 mg/m3, cell density from 144,108 thousand cell/l to 2,061 million cell/l, averaged 746,646 thousand cell/l. The minimum estimates of quantitative indices were recorded at station 3 (cell density - 144.108 thousand cell/l, biomass - 24.825 mg/m3). The maximum estimates of the colonies density were recorded at stations 2 (2,061 million cell/l) and 8 (1913.581 million cell/l), where the mass development of green algae Ankistrodesmus convolutus Corda and Scenedesmus quadricauda (Turp.) Breb. was observed, and the maximum boimass estimates were recorded at station 4 (the dominant was a dinoflagellate alga Heterocapsa triquetra (Ehr.) Stein). Among divisions, the bluegreen algae (22 % - 90 % of the total abundance) dominated almost at all stations by numbers, yielding to green algae at stations 2 and 8 (54-59 % of the total abundance) and diatom algae at stations 5 and 7 (82-86 %). Green algae (30-79 % of the total biomass) dominated by biomass at stations 1, 2, 5, and 8, located in the northern part of the bay, whereas in the southern part the diatom algae (58-93 %) dominated at stations 5, 6, 7, 9 and 10, excluding stations 4 and 11, where dinoflagellates prevailed (66 % - 81 % of the total biomass) (Appendix 2.6.2). Seven dominating species (20-87 % of the total abundance) were distinguished by abundance in the study region: in the northern part – green algae Ankistrodesmus convolutus Corda. and Scenedesmus quadricauda (Turp.) Breb., in the southern part – bluegreen algae Microcystis aeruginosa Kutz., Coelosphaerium kuetzingianum Nag. f. Kuetzingianum, Anabaena spiroides Kleb., Lyngbia sp,. Merismopedia tenuissima Lemm. Different species dominated at different stations by biomass: diatoms Amphiprora sp., Melosira varians Ag., Thalassiosira eccentrica (Ehr.) Cl. and dinoflagellate Heterocapsa triquetra (Ehr.) Stein. Thus, species of the neritic complex formed the base of phytoplankton community of Piltun Bay in September 2002. In the study region the widely distributed species: cosmopolites and boreal species dominated. In the study region the mean estimate of biomass was 355,51 mg/m3, cell density – 746,646 thousand cell/l. Station 3 was the poorest regarding to phytoplankton. The maximum estimates of colonies density were recorded at stations 2 and 8, where the mass development of green algae Ankistrodesmus convolutus Corda and Scenedesmus quadricauda (Turp.) Breb.was observed, the maximum biomass estimates – at station 4 (the dominant was a dinoflagellate alga Heterocapsa triquetra (Ehr.) Stein). Bluegreen and green algae made the main contribution to the abundance formation, and diatom and dinoflagellate algae contributed greatly to the biomass formation.

2.7. Zooplankton of the Piltun Bay

2.7.1. Description of zooplankton by the archive and literary data In 1999, only 16 animal forms belonging to 2 types and 3 classes were found from samples obtained during the surface water filtration, including 1 benthic form of the order Coleoptera and 1 neiston form of the suborder Collembola. Zooplankton fauna was represented, mainly, by species common for the freshened waters. Zooplankton being observed in mass in the coastal zone, but enduring a significant 34 freshening, for example, Pseudocalanus minutus1 (a habitat salinity amplitude is from 33 до 7 о /оо) was watched at the daily station. The order of copepods was represented the mostly complete (9 forms). The mean zooplankton biomass was 141,4 mg/g3. The maximum densities of catches were observed at individual stations of the very northern transect of the lagoon (st. 6 – 1047,5 mg/m3) and in the central part (st. 18 – 297 mg/m3) under the water salinity 0.05-0.41 ‰. A distribution pattern of biomass minimum estimates (from 2 to 15 mg/m3) was mosaic. Copepodids and adult specimens from the family Temoridae: Eurytemora gracilis and Eurytemora herdmanni dominated by numbers; the mean number of the representatives of this genus was 3988 ind./m3. The maximum density of species the genus Eurytemora was recorded in the northern part of the bay. The biomass of the noted species was 78.48 % of the total biomass over the bay. Fish larvae made up about 15 % of the total biomass. Based on the station similarity by the Shoener’s index, the species complex with dominants Eurytemora gracilis and Sinocalanus tenellus was distinguished. A total of 8 plankton forms entered the complex composition; the mean number of organisms was 10258 ind./m3, mean biomass 337,75 mg/m3. Copepods Eurytemora gracilis (3703 ind./m3; 189.53 mg/m3) and Sinocalanus tenellus (690 ind./m3; 0,7743 mg/m3) dominated in the community. These species formed 76,5 % of the total biomass. In addition, four copepod species more and fish larvae were common for this community; a systematic belonging of the latter ones is not identified for the present moment. The biomass of the mentioned organisms was a little more than 23 % of the total biomass of this community. Early copepodids of the genus Eurytemora (5250 ind./m3) dominated among the typical species by numbers; it is difficult to identify them up to a species at this stage of development. Their biomass was more than 51 % of the total biomass. Another complex was formed by Pseudocalanus minutus1, Acartia clausi2, and Eurytemora gracilis. The mean biomass of this complex was significantly lower than the index of the above community – 23.61 mg/m3, abundance 866 ind./m3. Three species, making up a base of biomass of this group (77.6 %), constituted the same proportion in the total abundance and were related to copepods. The typical species were represented both by copepods and gammarides, which had a high relative biomass, although being occurred sporadically. Among the typical species, nauplii of copepods (64 % of the number of typical species) prevailed by numbers, although having insignificant biomass (0.46 mg/m3). In the third complex, freshwater Sinocalanus tenellus were the dominants; their biomass was 65 % of the total estimate at 60 % of the total abundance. Copepods Pseudocalanus minutus and Eurytemora herdmani, which numbers constituted 5 ind./m3 for each species, and biomass did not exceed 0.5 mg/m3 were recorded from samples among other species of the indicated group of stations. We should note that these species were common for the coastal waters of northeastern Sakhalin. It needs to be noted that it is impossible to monitor a relationship between biomass of plankton animals, salinity, and time period for fishing by the results of the performed survey; this proves the absence of the distinctly separated water masses in the Piltun Bay and a significant confusion of the bay waters. Thus, zooplankton of the Piltun Bay is presented, mainly, by freshwater forms. The maximum biomass of zooplankters was recorded in the northern freshwater part of the bay (1047,5 mg/m3). The mean biomass was 141,4 mg/m3. Three main zooplankton complexes were described: • A group Eurytemora gracilis + Sinocalanus tenellus (a total of 8 forms; mean abundance 10258 ind./m3; mean biomass 337,75 mg/m3)

1 At present this species is redetermined as Pseudocalanus newmani 2 At present this species is redetermined as Acartia hudsonica. 35 • A group Pseudocalanus minutus + Acartia clausi + Eurytemora gracilis (a total of 12 forms; mean abundance 866 ind./m3; mean biomass 23,61 mg/m3) • A group Sinocalanus tenellus (a total of 3 species; mean abundance 25 ind./m3; mean biomass 2,3 mg/m3) (Labay et al., 1999). By the 1999 data of ECS, a total of 14 species of plankton animals belonging to 7 taxonomic groups of organisms were found in the Piltun Bay during zooplankton surveys. At 10 stations 10 zooplankton species belonging to 4 groups of organisms were recorded from samples. Copepods dominated in the species composition making up 57 % of species. The representatives of this zooplankton group were found at all stations, except for station 14 located in the mouth of Erri River. Of other groups of plankton organisms, amphipods were found from two samples, insect larvae occurred at station 14, and fish larvae at station 18. The mean biomass of plankton organisms in the Piltun Bay was 141,4 mg/m3. The maximum biomass of zooplankton (1047,5 mg/m3) was recorded in the very northern part of the bay. The rather high biomass of zooplankton (297 mg/m3) was recorded also in the northern part of the bay west of Cape Laida. At the rest stations the biomass estimates varied within 2-21 mg/m3. Copepods Eurytemora gracilis and Sinocalanus tenellus dominated in samples by biomass. The mean abundance of plankton organisms from samples was 4260 ind./m3. The maximum zooplankton number (34750 ind./m3) was recorded in the very northern part of the bay. The rather high abundance of zooplankton (6115 ind./m3) was recorded in the northern part of the bay. At the rest stations the numbers of plankton organisms varied within 5-1070 ind./m3. Juvenile copepod specimens from the genus Eurytemora and a copepod Eurytemora gracilis dominated in samples by numbers. At the daily station along the bar coast in the region of Cape Ozerny the mean zooplankton biomass was 51,5 mg/m3, abundance - 1953 ind./m3. On the whole, a temporal changeability in zooplankton quantitative indices was characterized by the maximum estimates in the period close to the high water. This is also related to the species diversity of plankton organisms (Ecological studies…, 2001).

2.7.2. Characteristic of zooplankton in 2002 A total of 13 forms of organisms from 5 groups (Table 2.7.1) were found in samples; among them, copepods (8 forms) were represented the most completely.

Table 2.7.1 A list of zooplankton organisms in the Piltun Bay in September 2002 № Group Form 1 Protozoa Tintina sp. 2 Notholca acuminata Rotatoria 3 Synchaeta sp. 4 Cladocera Chydorus sp. 5 Sinocalanus tenellus 6 Schmackeria inopina 7 Eurytemora con. raboti 8 Acartia hudsonica Copepoda 9 Oithona similis 10 Harpacticoidae indet. 11 Ergasilus sp. 12 Nauplii copepoda 13 Hydracarina Hydracarina indet

Due to the relatively small depth of the bay, a great number of the near-bottom forms were observed in samples. The majority of species are related to brackish and euryhaline ones. 36 The abundance of zooplankters (Table 2.7.2) in the bay varied within 300,0-72000,0 ind./m3, biomass 1,56-406,30 mg/m3, averaged 137,85 mg/m3. Nauplii of different copepods dominated both by biomass and abundance. We should note the occurrence of the free-living stages of ergasilides – gill fish parasites in the plankton.

Table 2.7.2 Zooplankton abundance and biomass in the Piltun Bay by stations Station Abundance, ind./m3 Biomass, mg/m3 Pil1 36975 343,19 Pil2 20550 79,58 Pil3 8150 114,7 Pil4 5800 29,6 Pil5 5200 73,2 Pil6 300 1,56 Pil7 700 15,47 Pil8 9850 85,75 Pil9 38900 406,3 Pil10 2250 18,5 Pil11 72000 348,5

Zooplankton is distributed unevenly over the bay area. This is connected with some factors: a level of water mineralization and temperature; river, brook, and tide run-off affect; uneven bottom relief; vegetation development. By the 2002 survey materials, the analysis of zooplankton similarity and difference by stations for all the bays according to the Shoener's index was done. A total of 33 zooplankton species and forms were identified during the 2002 surveys in the bays of northeastern Sakhalin (Appendix 2.7.1). As a result, three zooplankton complexes (groups) were distinguished (Fig. 2.7.1), common for all the bays.

Fig. 2.7.1. Dendrogram of similarity of zooplankton stations in the northeastern Sakhalin bays in 2002 by the Shoener’s index

37 The first group (a dominant species Copepoda nauplii) is marked red on the dendrogram. Its mean biomass was 251,57 mg/m3, mean abundance 45878,9 ind/m3 (Appendix 2.7.2). Nauplii of different copepods (mainly Euritemora and Acartia) dominated, reaching in sum 45,5 % of the total biomass. The second group (a dominant species Acartia hudsonica) is marked green on the dendrogram. It timed to the sites at the outlet of the bays undergrown with Zostera. Its mean biomass was 140,74 mg/m3, mean abundance 8723,8 ind/m3 (Appendix 2.7.3). Acartia hudsonica and its juveniles with some juveniles of A. longiremis dominated, reaching in sum 54,6 % of the total biomass. The third group (dominant species Euritemora herdmani + Acartia spp.) is marked blue on the dendrogram. It had the highest mean biomass - 404,62 mg/m3, mean abundance 17099,7 ind/m3 (Appendix 2.7.4). Euritemora herdmani and Acartia hudsonicai and its juveniles with some juveniles of A. longiremis dominated, reaching in sum 69,4 % of the total biomass. The representatives of genera Schmackeria and Sinocalanus constituted a significant proportion in the total biomass too. A spatial distribution of groups in the Piltun Bay is given in Fig. 2.7.2.

38

Fig. 2.7.2. Distribution of zooplankton complexes in the Piltun Bay in 2002

39 2.8. Benthos of the Piltun Bay

2.8.1. General characteristics of benthos Benthos studies of the Piltun Bay were carried out by the complex expedition of SakhNIRO and ECS in June-July 1999 (Labay et al., 1999, 2000). The data of 50 dredged stations were described. Sampling was being conducted with the help of Petersen's grab (0.025 m2) or Levanidov's benthometer (0.16 m2). A total of 17 algal and higher plant species were found in the Piltun Bay in June-July 1999 (Appendix 2.8.1). Only one species was observed among diatoms, three species among bluegreen algae, and six species among green algae. The higher plants were represented the most mass (7 species). Marine grasses of the genus Zostera, Ruppia cf. maritime, algae Cladophora cf. Glomerata, and pondweeds were the key species. A distribution of the general phytobenthos biomass had a heterogeneous character (Fig. 2.8.1). In general over the bay, the phytobenthos biomass varied from 0.2 to 1709.1 g/m2, averaged 135.5 g/m2. Three sites with high biomasses were distinguished; to the periphery of them the biomass declined. In the southern part of the bay a site with the maximum phytobenthos biomass (467.4 g/m2) appeared at station 40 located on the sandy ground at the depth of 0.8 m. The mean phytobenthos biomass at this site was 78.2 g/m2, varying from 0.4 to 467.4 g/m2. The base of biomass was formed by Zostera japonica. In the central part of the bay the maximum biomass, making up, mainly, Ruppia cf. maritima, was timed to the mouth of Sabo River, averaged 78.4 g/m2, ranging from 0.2 to 470,9 g/m2. The highest estimates of phytobenthos biomass (2.3– 1709.5 g/m2; averaged 210.8 g/m2) are formed by the filamentous algae, Cladophora cf. glomerata in particular. The highest phytobenthos biomasses were timed to the near-mouth sites of rivers Paromay, Piltun, Erri, and Sabo, where the content of biogenic elements was higher (Labay et al., 1999); this is favorable to growth and development of water vegetation. Among zoobenthos organisms, a total of 102 species and subspecies were found (Table 2.8.1). Larvae of Chironomidae (24), Oligochaeta (22), Amphipoda (9), and Gastropoda (7) dominated by species numbers. Polychaetes and bivalves presented by 4 species. Bivalves played the dominating part in forming the Piltun Bay biomass. Amphipods, larval chironomides, and bivalves were the most abundant. Bivalves Macoma balthica and Corbicula japonica and amphipod Kamaka kuthae were the key species of the Piltun Bay zoobenthos.

Table 2.8.1 Characteristics of abundance of the main macrozoobenthos groups in the Piltun Bay Taxonomic groups Numbers of N, ind./m2 В, g/m2 species Polychaeta 4 49 1.2 Oligochaeta 22 - 1.3 Amphipoda 9 2620 1.5 Chironomidae larvae 24 374 0.8 Bivalvia 4 135 15.0 Gastropoda 7 53 0.5 Isopoda 3 23 0.3 Other 29 107 0.4 Total 102 3361 21.0

A distribution of zoobenthos biomass had a gradient character with the gradual decreasing in biomass from the near-strait part toward the northern and, to the less extent, southern codened sites (Fig. 2.8.2).

40

53.35 1300 р. Эрри

1000 оз. Лиман м. Бон - Бон 750

500

м. Лайда 300

м. Лебединный 200 м. Верхотурова

100 р. Сабо

м. Чиркпа о. Врангеля 0

р. Кадыланьи

м. Агиво

р. Мухто

р. Паромай

52.85 р. Пильтун 143 143.3 Fig. 2.8.1. Distribution of the total phytobenthos biomass (g/m2) in the Piltun Bay in 1999 (according to Labay et al., 1999) 41 The individual small zones of the higher biomass are common for the river mouths. A distribution of bivalve biomass, making up a base of animal inhabitants, commonly repeats the distribution of the zoobenthos biomass in general. The maximum biomass of Bivalvia (more than 200 g/m2) was recorded at the southern near-strait site. Chironomidae larvae were the most abundant (to 20 g/m2) in the northern freshened part of the lagoon.

53.35

р. Эрри 200

оз. Лиман м. Бон - Бон 150

100

м. Лайда

50

м. Лебединный м. Верхотурова 25

р. Сабо

м. Чиркпа о. Врангеля 0

р. Кадыланьи

м. Агиво

р. Мухто

р. Паромай

52.85 р. Пильтун 143 143.3

Fig. 2.8.2. Distribution of the total zoobenthos biomass (g/m2) in the Piltun Bay in 1999 (according to Labay et al., 1999) 42

2.8.2. Benthos communities Several macrobenthos communities are distinguished in the Piltun Bay (Fig. 2.8.3).

53.35

р. Эрри . 1 оз. Лиман м. Бон - Бон 2

3

м. Лайда 4

м. Лебединный м. Верхотурова

р. Сабо

м. Чиркпа о. Врангеля

р. Кадыланьи

м. Агиво

р. Мухто

р. Паро май

52.85 р. Пильтун

143 143.3 Fig. 2.8.3. Distribution of the main macrobenthos communities in the Piltun Bay in 1999. Communities: 1 - Zostera japonica; 2 - Corbicula japonica; 3 - Potamogeton perfolatus + Kamaka kutchae; 4 - Potamogeton perfolatus (according to Labay et al., 1999).

43 Community Potamogeton perfolatus + Kamaka kutchae This community occupies the middle part of the lagoon and the coastal sites from the Kadylanyi River along the western coast to Cape Laida along the eastern coast. The community is mainly distributed on slimy-sand grounds at the depth of 0.4 – 2.8 m. A total of 41 representatives of macrobenthos enter the community composition; of them Chironomidae larvae are the most diverse (15 species) (Table 2.8.2).

Table 2.8.2 Composition and structure of the community Potamogeton perfolatus +Kamaka kutchae Species Group N, ind./m2 В, g/m2 Biomass, % F, % Plants Potamogeton perfolatus Magnoliophyta + 5.37 29.38 100 Zostera japonica Magnoliophyta + 0.35 1.89 25 Ruppia maritima Magnoliophyta + 0.02 0.12 25 Cladophora glomerata Algae + 1.91 10.43 75 Tolypothrix sp. Algae + 0.57 3.09 50 Melosira sp. Algae + 0.30 1.64 50 Chlorophyta indet. Algae + 0.79 4.32 25 Phytobenthos, total 9.30 Animals Kamaka kutchae Amphipoda 7390 3.18 17.37 100 Spirosperma apapillatus Oligochaeta + 1.84 10.06 50 Propappus volki Oligochaeta + 1.10 6.00 25 Glyptotendipes paripes Diptera 273 0.99 5.39 50 Dicrotendipes pelochloris Diptera 263 0.59 3.24 75 Uncinais uncinata Oligochaeta + 0.24 1.30 25 Donacia sp. Coleoptera 35 0.22 1.22 50 Cincinna sirotskii Gastropoda 13 0.17 0.93 25 Eogammarus kygi Amphipoda 18 0.11 0.60 75 Neomysis awatschensis Mysidae 6 0.09 0.49 50 Rhyacodrilus coccineous Oligochaeta + 0.08 0.44 25 Paranais litoralis Oligochaeta + 0.05 0.26 25 Locustogammarus hirsutimanus Amphipoda 3 0.04 0.23 25 Polipedium (Tripodura) Diptera 168 0.04 0.23 50 bicrenatum Cryptochironomus cf. defectus Diptera 8 0.04 0.21 25 Pristinella bilobata Oligochaeta + 0.03 0.17 25 Procladius sp. Diptera 66 0.03 0.15 25 Glyptotendipes gripekoveni Diptera 33 0.02 0.10 25 Cladotanytarsus cf. mancus Diptera 367 0.02 0.09 25 Anisus acronicus Gastropoda 2 0.02 0.09 25 Paratanytarsus sp. Diptera 13 0.02 0.09 25 Oecetis ochracea Trichoptera 22 0.02 0.08 50 Paratendipes intermedius Diptera 42 0.01 0.06 75 Chironominae indet. Diptera 29 0.01 0.06 75 Cladopelma cf. Lateralis Diptera 50 0.01 0.06 50 Psectrocladius cf. Barbimanus Diptera 7 0.01 0.06 25 Tanytarsus verralli Diptera 56 0.00 0.03 75 Haliplus sp. Coleoptera 5 0.00 0.02 25 Nais barbata Oligochaeta + 0.00 0.02 25 Limnodrilus profundicola Oligochaeta + 0.00 0.02 25 Cladotanytarsus cf. Vanderwulpi Diptera 106 0.00 0.01 25 Cricotopus cf. Sylvestris Diptera 2 0.00 0.00 25 Mystacides nigra Trichoptera 2 0.00 0.00 25 Lamprops korroensis Cumacea 2 0.00 0.00 25 Zoobenthos, total 8977 8.98 Total biomass 18.28

44 The mean biomass of the community was insignificant and constitutes 18.28 g/m2. Dominant species made up 5.37 g/m2 and 3.18 g/m2, respectively. The mean density of macrobenthos organisms was rather high and constituted more than 8000 ind./m2. Amphipods K. Kuthae dominated by abundance. The colony density of this species varied by stations from 3225 to 29558 ind./m2. The abundance of chironomide larvae, reaching more than 250 ind./m2 was high too. Such high indices of the colonies density in community for these organisms, evidently, are explained by the closeness of the mouth sites of rivers Kadylanyi and Sabo, flowing river waters enriched by the biogenic elements to the lagoon. Being the gathering detritophagans, K. kuthae and chironomide larvae find at this site the feeding elements necessary for their vital activity. A green alga Cladophora glomerata, polychaete Spirosperma apapillatus, and chironomide larvae Glyptotendipes paripes, Dicrotendipes pelochloris were distinguished among the typical species.

Community Potamogeton perfolatus The pondweed community Potamogeton perfolatus, observed at stations 1, 2, 6, 7, 14, 30, and 44 was distinguished at the high enough level of similarity. This community was timed to the freshwater northern part of the bay. It was distributed from the coastal shallow zone to the depth of 1.9 m, mainly on sandy grounds. 3 species of phytobenthos and 28 representatives of zoobenthos entered the community composition (Table 2.8.3). Polychaetes (7 species), freshwater gastropods, chironomide and trichoptera larvae (by 4 species in each group) were the most diverse by species numbers.

Table 2.8.3 Composition and structure of the community Potamogeton perfolatus Species Group N, ind./m2 В, g/m2 Biomass, % F, % Plants Potamogeton perfolatus Magnoliophyta + 53.49 70.99 100 Ruppia occidentalis Magnoliophyta + 17.07 22.65 14 Tolypothrix sp. Algae + 0.29 0.38 14 Phytobenthos, total 70.84 Animals Anisus acronicus Gastropoda 13 1.09 1.44 14 Fluviocingula nipponica Gastropoda 23 0.77 1.02 14 Kamaka kutchae Amphipoda 12 0.45 0.60 71 Cincinna sirotskii Gastropoda 208 0.39 0.52 14 Uncinais uncinata Oligochaeta 0 0.36 0.48 14 Pisidium decurtatum Bivalvia 894 0.34 0.45 14 Donacia sp. Coleoptera 24 0.30 0.40 43 Cryptochironomus cf. defectus Diptera 53 0.18 0.24 29 Spirosperma velutinus Oligochaeta 0 0.16 0.21 29 Limnodrilus profundicola Oligochaeta 1 0.14 0.19 14 Limnaea schubinae Gastropoda 120 0.13 0.17 14 Eogammarus kygi Amphipoda 15 0.09 0.12 57 Spirosperma nikolskyi Oligochaeta 0 0.04 0.06 14 Eteone longa Polychaeta 25 0.02 0.03 14 Turbellaria fam. sp. Turbellaria 4 0.01 0.01 14 Neomysis awatschensis Mysidae 0 0.01 0.01 14 Oecetis ochracea Trichoptera 4 0.00 0.01 57 Polipedium (Tripodura) Diptera 1 0.00 0.01 14 bicrenatum Mystacides nigra Trichoptera 3 0.00 0.01 14 Mystacides longicornis Trichoptera 0 0.00 0.00 14 Asellus hilgendorphi Isopoda 0 0.00 0.00 14 Tubifex tubifex Oligochaeta 0 0.00 0.00 14 Lumbriculus variegatus Oligochaeta 0 0.00 0.00 14 Lebertia porosa Hydrachnidia 0 0.00 0.00 14 45

Species Group N, ind./m2 В, g/m2 Biomass, % F, % Nais barbata Oligochaeta 0 0.00 0.00 14 Glyptotendipes paripes Diptera + 0.00 0.00 14 Glyptotendipes glaucus Diptera 26 0.00 0.00 14 Molanna angustata Trichoptera 0 0.00 0.00 14 Zoobenthos, total 1426 4.51 Total biomass of the community 75.35

The mean biomass of the community was 75.35 g/m2, where 70 % of the biomass was formed by the dominant pondweed P. perfolatus. The mean density of macrobenthos colonies was 1426 ind./m2. A bivalve Pisidium decurtatum and gastropods Cincinna sirotskii, Limnaea schubinae made up the highest density. Amphipods Kamaka kuthae and larvae of leaves-eating beetles Donacia sp. are typical. The major part of organisms was related to the secondary species with mean biomasses not exceeding 0.01 g/m2. As a rule, these species occurred in the community sporadically. The above-described communities characterize, in general, those of the freshwater macrozoobenthos, modified by the influence of brackish waters in this or that degree. The commonly brackish communities are located in a zone of fresh and seawater confusion, where the main dominants are marine grass Zostera japonica and bivalves M. balthica and C. japonica.

Community Zostera japonica Stations 34, 40, 39, 33, 47, 36, 27, 32, 26, and 42, timed to the brackish part of the bay and characterizing the community Zostera japonica on sandy, silty, and silty-sand grounds at the depth to 1,5 m in the southern part of the bay and in its near-strait site were distinguished in the well isolated claster. A total of 55 representatives of macrobenthos entered the community composition; of them, 9 species were related to phytobenthos (Table 2.8.4).

Table 2.8.4 Composition and structure of the community Zostera japonica Species Group N, ind./m2 В, g/m2 Biomass, % F, % Plants Zostera japonica Magnoliophyta + 86.73 84.09 100 Stigonema sp. Algae + 3.87 3.7 20 Cladophora glomerata Algae + 2.57 2.5 20 Zostera marina Magnoliophyta + 0.84 0.8 30 Ulothrix implexa Algae + 0.86 0.8 20 Spirogyra sp. Algae + 0.72 0.7 20 Enteromorpha sp. Algae + 0.77 0.7 10 Melosira sp. Algae + 0.43 0.4 10 Chlorophyta indet. Algae + 0.05 0.0 10 Phytobenthos, total 96.84 Animals Glyptotendipes paripes Diptera 709 1.98 1.9 50 Kamaka kutchae Amphipoda 3694 1.15 1.1 20 Hediste japonica Polychaeta 203 0.75 0.7 20 Spirosperma apapillatus Oligochaeta + 0.45 0.4 20 Spirosperma velutinus Oligochaeta + 0.43 0.4 10 Paranais litoralis Oligochaeta + 0.27 0.3 20 Dicrotendipes pelochloris Diptera 54 0.25 0.2 20 Eogammarus kygi Amphipoda 28 0.21 0.2 40 Phyllodoce groenlandica Polychaeta 1 0.11 0.1 10 Cryptochironomus cf. defectus Diptera 24 0.09 0.1 20 Locustogammarus hirsutimanus Amphipoda 26 0.08 0.1 20 Pontoporeia affinis Amphipoda 40 0.07 0.1 10 Lamprops korroensis Cumacea 31 0.06 0.1 30 Propappus volki Oligochaeta + 0.06 0.1 10 46

Species Group N, ind./m2 В, g/m2 Biomass, % F, % Neomysis awatschensis Mysidae 24 0.05 0.0 40 Nais barbata Oligochaeta + 0.04 0.0 20 Turbellaria fam. sp. Turbellaria 3 0.03 0.0 10 Eogammarus tiusсhovi Amphipoda 9 0.03 0.0 30 Anisus stroemi Gastropoda 1 0.03 0.0 10 Donacia sp. Coleoptera 1 0.02 0.0 10 Cladopelma cf. lateralis Diptera 52 0.02 0.0 20 Psectrocladius cf. barbimanus Diptera 23 0.01 0.0 50 Dogielinotus moskvitini Amphipoda 10 0.01 0.0 30 Tubifex tubifex Oligochaeta + 0.01 0.0 10 Saduria entomon Isopoda 6 0.01 0.0 30 Anisus acronicus Gastropoda 1 0.01 0.0 10 Polipedium (Tripodura) Diptera 36 0.01 0.0 20 bicrenatum Limnodrilus hoffmeisteri Oligochaeta + 0.01 0.0 10 Stictochironomus cf. histrio Diptera 1 0.00 0.0 10 Cricotopus cf. sylvestris Diptera 9 0.00 0.0 20 Einfeldia sp. Diptera 2 0.00 0.0 10 Oecetis ochracea Trichoptera 2 0.00 0.0 20 Paratendipes intermedius Diptera 7 0.00 0.0 10 Chaetogaster langi Oligochaeta + 0.00 0.0 10 Corophium steinegeri Amphipoda 1 0.00 0.0 10 Chironominae indet. Diptera 3 0.00 0.0 10 Lumbriculus variegatus Oligochaeta 2 0.00 0.0 10 Cladotanytarsus cf. mancus Diptera 3 0.00 0.0 10 Aulodrilus limnobius Oligochaeta + 0.00 0.0 10 Eteone longa Polychaeta 7 0.00 0.0 10 Enchytraeus albidus Oligochaeta + 0.00 0.0 10 Tanytarsus verralli Diptera 3 0.00 0.0 10 Procladius sp. Diptera 1 0.00 0.0 10 Haliplus sp. Coleoptera + 0.00 0.0 10 Ischyrocerus elongatus Amphipoda 1 0.00 0.0 10 Psammoryctides barbaus Oligochaeta + 0.00 0.0 10 Zoobenthos, total 4994 6.25 Total biomass of the community 103.09

A number of species at stations varied from 4 to 18. Larval insects and polychaetes (14 and 12 species) were the most diverse. Amphipods were represented by 8 species, polychaetes – 3 species. The other groups of macrobenthos were represented by 1-3 species. The mean biomass of community was more than 100 g/m2. The dominant species Z. japonica constituted more than 86 % of the total community biomass. The mean density of macrobenthos colonies constituted 4994 ind./m2. Larval insects, amphipods, and polychaetes made up the highest density. Of the typical species for II order the following species were recorded in the community: green algae C. glomerata and Stigonema sp., chironomide larvae G. Paripes, and amphipods K. kutchae. Their summarized biomass was 9.3 % of the total biomass, abundance 88 % of the mean community density. Major species in the community were related to the secondary species. Their mean biomass did not exceed 1 g/m2, and frequency, as a rule, was less than 30 %. More than 50 % of the secondary species were found only at one station.

Community Corbicula japonica Stations 12, 19, 13, 45, 46, and 11, characterizing the community C. japonica were distinguished into the isolated claster. The community occurred on silty and silty-sand grounds at the depth of 1.3 – 2.3 m and was discontinuous, occupying two areas in the bay: in central and northwestern parts. The area in the central part can be distinguished into the individual group with the dominant species Corbicula japonica and co-dominants M. balthica and Potamocorbula amurensis. In general, a total number of species in the community reached 21 (Table 2.8.5). 47 Polychaetes (6 species) were the most diverse in the community. Phytobenthos was represented by 4 species of flower plants. The mean biomass of the community was 96.33 g/m2. The main biomass (92.11 g/m2) was formed by bivalves C. japonica, M. balthica and P. amurensis. Together with K. kutchae they formed the highest density of macrobenthos colonies too.

Table 2.8.5 Composition and structure of the community Corbicula japonica Species Group Ind./m2 G/m2 Biomass, % F, % Plants Potamogeton perfolatus Magnoliophyta + 0.63 0.65 17 Ruppia occidentalis Magnoliophyta + 0.53 0.55 17 Ruppia maritima Magnoliophyta + 1.24 1.29 17 Myriophyllum spicatum Magnoliophyta + 0.38 0.39 17 Phytobenthos, total 2.78 Animals Corbicula japonica Bivalvia 251 56.89 59.05 100 Macoma balthica Bivalvia 698 24.33 25.26 33 Potamocarbula amurensis Bivalvia 118 10.89 11.30 33 Kamaka kutchae Amphipoda 871 0.35 0.36 50 Limnodrilus hoffmeisteri Oligochaeta + 0.40 0.41 83 Donacia sp. Coleoptera 22 0.20 0.21 17 Uncinais uncinata Oligochaeta + 0.18 0.19 33 Eogammarus kygi Amphipoda 20 0.13 0.14 50 Chironomus sp.1 Diptera 2 0.07 0.07 17 Lumbriculus variegatus Oligochaeta + 0.06 0.06 33 Fluviocingula nipponica Gastropoda 11 0.02 0.02 17 Eteone longa Polychaeta 9 0.01 0.01 17 Hediste japonica Polychaeta 2 0.01 0.01 17 Dogielinotus moskvitini Amphipoda 2 0.00 0.00 17 Limnodrilus profundicola Oligochaeta + 0.00 0.00 17 Propappus volki Oligochaeta + 0.00 0.00 17 Spirosperma velutinus Oligochaeta + 0.00 0.00 17 Zoobenthos, total 2006 93.55 Total biomass of the community 96.33

These species constituted 97 % of the total community abundance. Like in the previous community, the majority of macrobenthos representatives were related to the secondary species. Their mean biomasses varied from 0.001 to 0.6 g/m2, and their abundance did not exceed 20 ind./m2. The distinguished group in the central part of the bay was characterized by the presence of brackish species in its composition, not found in the northwestern part. They included two species of bivalves (M. balthica and P. amurensis), and two species of polychaetes (Eteone longa and Hediste japonica). Taking into account peculiarities of the hydrologic regime of the bay, a central brackish part is more favorable for development of these species in contrast to the northern freshwater part.

48 A spatial distribution of macrobenthos communities in the Piltun Bay, evidently, is determined by the mean annual distribution of the near-bottom salinity. The northwestern part of the bay practically is not exposed to the influence of seawaters and characterized by the freshwater communities with the domination of pondweed and Corbicula. A distribution of freshwater communities is connected, to the great extent, with the distribution of near-mouth sites and has a mosaic character determined both by the volume and character of the fluid and solid run-off, and the peculiarities of the near-mouth sedimentation processes.

Benthos of strait joining the bay with the sea A detail description of bottom inhabitants of the near-mouth part of lagoon strait joining Piltun Bay with the sea was performed by V.D. Tabunkov et al. (1988) by the data of complex expedition of Zoological Institute of AS USSR in July-August 1978 at R/V “Posseidon”. By the data of Tabunkov et al. (1988), a littoral zone of the western side of the strait throat is practically lifeless. In the eastern part, benthos is rather abundant and presented by the biocenosis Blidingia minima (Fig. 2.8.4, Table 2.8.6). A total of 13 species of plants and animals were found. The inhabitants were represented, mainly, by the epifauna organisms, among which amphipods dominated. M. balthica was the most abundant in the infauna. The base of biocenosis biomass was formed by autotrophic organisms (96 %); detritophagans prevailed among animals.

Fig. 2.8.4. Vertical distribution of communities in the strait of Piltun Bay (А – a mouth part, B – a near-mouth part) (according to Tabunkov et al., 1988). Indication: 1 – Blidingia minima; 2 – colonial diatoms, 3 – Sertularia cupressoides, 4 – Arenicola marina, 5 – Macoma balthica, 6 – Mya uxenensis, 7 – Dogielinotus moskvitini, 8 – other amphipods, 9 – Saduria entomon; communities: I - Blidingia minima, II - Macoma balthica, III – Liocyma fluctuosa+ Macoma balthica, IV и V – Mytilus trossulus, VI - Mytilus trossulus +Macoma sp. + Macoma balthica + Arenicola marina, VII - Sertularia cupressoides + Mya uxenensis, VIII - – Dogielinotus moskvitini, IX – colonial diatoms, X – Zostera marina + Macoma balthica + Littorina sitkana. Figures left and right of thick vertical lines indicate depths (m).

49

Table 2.8.6 Composition of the biocenosis Blidingia minima Species Group N, ind./m2 В, g/m2 Plants Blidingia minima Chlorophyta 150 173.32 Epifauna Amphipoda (2 species) Amphipoda 200 2,84 Dogielinotus moskvitini Amphipoda 117 0,83 Spinulogammarus sp. Amphipoda 68 0.54 Saduria entomon Isopoda 218 0.45 Anisogammarus sp. Amphipoda 110 0.42 Mytilus trossulus Bivalvia 17 0.34 Ischyrocerus sp. Amphipoda 100 0.33 Infauna Macoma balthica Bivalvia 50 0.8 Spio filicornis Polychaeta 17 0.67 Ampharete arctica Polychaeta 17 0.2 Oligochaeta indet. Oligochaeta 15 0.05 Total 13 1079 180,79

Biocenosis Macoma balthica was found in the very upper horizon of the sublittoral zone at depths to 1 m on sandy grounds without vegetation (Fig. 2.8.4, Table 2.8.7). The base of biomass was formed by the infauna representatives (99,4 %). Bivalves M. trossulus occurred close to the lower boundary of biocenosis, but their biomass was extremely low. Two species of bivalves: M. balthica and Liocyma fluctuosa (99.35 %) formed the base of biomass. A trophic structure of biocenosis was determined by the domination of detritophagans (90,7 %).

Table 2.8.7 Composition of the biocenosis Macoma balthica Species Group N, ind./m2 В, g/m2 Nektobenthos Neomysis chernjavskii Mysidae 10 0.09 Epifauna Amphipoda (3 species) Amphipoda 100 0.59 Saduria entomon Isopoda 40 0.07 Mytilus trossulus Bivalvia 10 0.01 Infauna Macoma balthica Bivalvia 160 109.2 Liocyma fluctuosa Bivalvia 10 10.5 Cumacea indet. Cumacea - 0.02 Total 10 330 120.68

Biocenosis Liocyma fluctuosa + Macoma balthica was observed from the western side at the same depths (Fig. 2.8.4, Table 2.8.8). Like in the above biocenosis, the representatives of infauna dominated, however, the change in dominants took place. The epifauna organisms formed insignificant biomass; actinians Bunodactis sp. and Phyllactis excelsa prevailed among them. In the trophic respect, sestonophagans dominated there (55,9 % of the total biomass); detritophagans formed only 38,1 % of the total biomass.

50 Table 2.8.8 Composition of the biocenosis Liocyma fluctuosa + Macoma balthica Species Group N, ind./m2 В, g/m2 Epifauna Bunodactis sp. Actiniaria 20 164.6 Phyllactis excelsa Actiniaria 10 40 Falsicingula sp. Gastropoda 880 7.2 Littorina sitkana Gastropoda 30 4.44 Capitellidae indet. Polychaeta 1.55 Mytilus trossulus Bivalvia 80 1.16 Saduria entomon Isopoda 240 0.8 Amphipoda indet. Amphipoda 40 0.16 Infauna Liocyma fluctuosa Bivalvia 1550 1901.5 Macoma balthica Bivalvia 1120 1283 Oligochaeta indet. Oligochaeta 120 0.3 Total 11 4090 3404.71

Biocenosis Mytilus trossulus was located by the both sides of the strait at depths more than 1 m (Fig. 2.8.4), however, from eastern and western sides it differed by composition and structure (Table 2.8.9, 2.8.10). From the western side this biocenosis extended to the depth of 6 m. There the epifauna included the greatest number of species (77 %). The base of biomass was formed by mussels (92.2 %). Only 3 species of bivalves forming a rather significant biomass (446 g/m2; 6,4 %) were found in the infauna composition. The base of the trophic structure of biocenosis was formed by filtrators and sestonophagans (94 %). From the eastern side the biocenosis was observed to the depth of 4 m. However, the greatest number of species occurred in the infauna (63,6 %). Mussels (91.8 %) also formed the base of biomass. The biomass of infauna organisms constituted only 5.7 %. The base of the trophic structure of biocenosis was formed by filtrators and sestonophagans (93.4 %).

Table 2.8.9 Composition of the biocenosis Mytilus trossulus from the western side of the strait Species Group N, ind./m2 В, g/m2 Epifauna Mytilus trossulus Bivalvia 2280 6400 Balanus sp. Cirripedia 268 81.2 Spinulogammarus sp. Amphipoda 176 4.712 Isopoda indet. Isopoda 148 3.476 Falsicingula sp. Gastropoda 64 1.024 Bunodactis sp. Actiniaria 76 0.576 Anisogammarus sp. Amphipoda 104 0.372 Ischyrocerus sp. Amphipoda 88 0.308 Amphipoda indet. Amphipoda 4 0.036 Pantopoda indet. Pantopoda 4 0.02 Infauna Macoma moesta Bivalvia 546 278 Macoma balthica Bivalvia 568 168 Mya priapus Bivalvia 8 0.284 Total 13 4334 6938.008 51

Table 2.8.10 Composition of the biocenosis Mytilus trossulus from the eastern side of the strait Species Group N, ind./m2 В, g/m2 Epifauna Mytilus trossulus Bivalvia 1050 1546,24 Saduria entomon Isopoda 20 40,55 Nereis pelagica Polychaeta 10 0.47 Anisogammarus sp. Amphipoda 20 0.24 Infauna Arenicola marina Polychaeta 50 29.9 Oligochaeta indet. Oligochaeta 5710 26.9 Mya japonica Bivalvia 50 20.1 Liocyma fluctuosa Bivalvia 60 16 Ampharete arctica Polychaeta 150 2.1 Capitella capitata Polychaeta 90 1.34 Chone teres Polychaeta 10 0.33 Total 13 4334 6938.008

From the eastern side of the strait, beginning from the depth of 4 m, the biocenosis Mytilus trossulus was replaced by the polymixed biocenosis Mytilus trossulus + Macoma calcarea + Macoma balthica + Arenicola marina (Fig. 2.8.4, Table 2.8.11). Biomasses of the dominating species of biocenosis were close and varied within 193-235 g/m2. The base of biomass was formed by the infauna species, although a half of noted species was related to the epifauna. Detritophagans prevailed in the trophic structure.

Table 2.8.11 Composition of the biocenosis Mytilus trossulus + Macoma calcarea + Macoma balthica + Arenicola marina Species Group N, ind./m2 В, g/m2 Epifauna Mytilus trossulus Bivalvia 20 235 Saduria entomon Isopoda 3210 37,4 Amphipoda (5 species) Amphipoda 830 2,71 Pontoporeia affinis Amphipoda 140 2.04 Oenopota sp. Gastropoda 10 0.98 Bunodactis sp. Actiniaria 10 0.05 Infauna Macoma calcarea Bivalvia 220 231 Macoma balthica Bivalvia 3210 225.7 Arenicola marina Polychaeta 210 193 Macoma moesta Bivalvia 30 8.24 Macoma sp. Bivalvia 30 7.36 Liocyma fluctuosa Bivalvia 10 7.33 Notomastus latericeus Polychaeta 10 0.81 Eteone ornata Polychaeta 10 0.08 Ampharete arctica Polychaeta 10 0.06 Total 19 4970 951.76

52 Biocenosis Sertularia cupressoides + Mya priapus was located in the central part of the fairway at depths of 6-7 m (Fig. 2.8.4, Table 2.8.12). There, the total number of species was lower than in the above biocenosis (15); about a half of species were related to the epifauna, which species formed 57,3 % of the total biomass. In the trophic structure of this biocenosis, filtrators and sestonophagans significantly exceeded the other groups by biomass (81,4 %).

Table 2.8.12 Composition of the biocenosis Sertularia cupressoides + Mya priapus Species Group N, ind./m2 В, g/m2 Epifauna Sertularia cupressoides Hydrozoa 1100 Saduria entomon Isopoda 7470 120 Phyllactis excelsa Actiniaria 90 87.8 Synidotea sp. Isopoda 870 60.9 Amphipoda (2 species) Amphipoda 540 2.07 Idotea sp. Isopoda 10 1 Ischyrocerus sp. Amphipoda 10 0.04 Infauna Mya priapus Bivalvia 20 845.9 Notomastus latericeus Polychaeta 3860 148.7 Arenicola marina Polychaeta 10 9.38 Ampharete arctica Polychaeta 480 6.4 Ampharete acutifrons Polychaeta 60 5.33 Nephthys ciliata Polychaeta 10 2.95 Chone teres Polychaeta 30 2.4 Total 15 20000 2392.87

2.9. Ichthyofauna of the Piltun Bay

Four bays of the northeastern Sakhalin Island (Piltun, Chaivo, Nyisky, and Nabil) have large rivers in their basins. Anadromous fishes, reproducing in rivers flowing into the bays, make up the main abundance and biomass in all these lagoons. So, regularities of changes in abundance and biomass in these lagoons have a general trend in many cases. The existing papers on the Piltun Bay ichthyofauna contain, mainly, the materials on species composition (Taranets, 1937б; Tabunkov et al., 1988; Zemnukhov et al., 2001; Safronov et al., 2003). During the expedition works carried out by the staff of Laboratory of Applied Ecology, SakhNIRO in June-July 1999, a total of 24 fish species belonging to 15 families were found in the Piltun Bay, including the following fish being not indicated before: Amur bitterling, Sakhalin lake minnow, common wild goldfish, and loach Cobitis lutheri (Labay et al., 1999). After summarizing the obtained data, the presented list includes not less than 47 fish species belonging to 21 families (Table 2.9.1). A general species composition of fishes in the bay is not similar in different years. Many sea species occurring in the bay in small numbers are not found there every year.

Table 2.9.1 A list of fish and fish-like species of the Piltun Bay Family Species and subspecies Petromyzontidae Lethenteron japonicum – arctic lamprey **Clupea pallasii – herring Clupeidae ****Sardinops sagax melanosticta – ivasi (west Pacific sardine) *Acipenser medirostris – Sakhalin sturgeon Acipenseridae *Huso dauricus – kaluga sturgeon 53

Family Species and subspecies Oncorhynchus gorbuscha – pink salmon Oncorhynchus keta – chum salmon Oncorhynchus masou – masu salmon Salmonidae Oncorhynchus kisutch – coho salmon ***Salvelinus leucomaenis – Sakhalin char *** Salvelinus malma krascheninnikovi – southern malma *Parahucho perryi – Sakhalin taimen Coregonidae Coregonus ussuriensis – Ussuri whitefish H. nipponensis – wakasagi Osmeridae H. olidus – pond smelt Osmerus mordax – Asiatic smelt, rainbow smelt Carassius auratus gibelio – common wild goldfish Phoxinus perenurus – Sakhalin lake minnow Rodeus sericeus – Amur bitterling Cyprinidae ***Tribolodon brandtii – eastern redfin ***Tribolodon ezoe – Pacific redfin ***Tribolodon hakuensis – big-scaled redfin Cobitis lutheri – loach Cobitidae Misgurnus nikolsky – Nikolsky's loach Balitoridae Barbatula toni – Siberian stone loach Gadus macrocephalus – Pacific cod Gadidae **Eleginus gracilis – saffron cod Mugilidae Mugil cephalus – Pacific mullet Gasterosteus aculeatus – threespine stickleback Pungitius pungitius – ninespine stickleback Gasterosteidae Pungitius sinensis – Amur stickleback Pungitius tymensis – Sakhalin stickleback Opisthocentrus ocellatus – spottyfin gunnel Stihaeidae Pholidapus dybowskii – Dybowsky's blenny Zoarcidae Zoarces elongates – Pacific eelpout Agonidae Brachyopsis segaliensis – long-snouted poacher Gobiidae Chaenogobius urotaenia Megalocottus platycephalus –flathead sculpin Cottidae Myoxocephalus jaok – plain sculpin Myoxocephalus stelleri – Steller's sculpin Hemitripteridae Hemitripterus villosus – sea raven Cyclopteridae Liparis kusnetzovi – Kuznetsov’s snailfish Ammodytidae Ammodytes hexapterus – Pacific sand lance Limanda aspera – yellowfin sole Limanda proboscideus – snout sole Limanda punctatissima – longsnout flounder Pleuronectidae ***Platichthys stellatus – starry flounder Liopsetta pinnifasciata – banded flounder Pleuronectes quadrituberculatus – Alaska plaice * Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the last years A species composition of ichthyofauna, and abundance and biomass of fishes in the bay are very dynamic. Marine euryhaline species (banded flounder Pleuronectes (Liopsetta) pinnifasciata, flathead sculpin Megalocottus platycephaluis, some adult species and juveniles of starry flounder Platihthys stellstus, and others) inhabit it during the major part of the year or constantly. Some anadromous fishes (Sakhalin char Salvelinus leucomaenis, pond smelts Hypomesus, sticklebacks Gasterosteidae, and others) leave the bay for the open sea only during a short period of time. Practically always the abundance and biomass of these fishes in the bay are relatively stable. At the same time, these indices for the other anadromous species (Pacific salmon Oncorhynchus, southern malma Salvelinus malma krascheninnikovi, big-scaled redfin Tribolodon hakuensis, and others) vary significantly during a year. Abundance and biomass of the non-abundant sea species (greenlings Hexagrammos, some species from the family 54 Pleuronectidae, and others), which inhabit the parts of lagoons adjoining to the straits, are not constant. The maximum fish biomass in the bay is observed in the period, when the greatest numbers of species (euryhaline, anadromous, and marine) inhabit it. As a rule, this takes place from July through October when species from all the groups occur in the bay. Of anadromous fishes, the most abundant species having great biomass (pink salmon Oncorhynchus gorbuscha, chum salmon O.keta, coho salmon O.kisutch, stone loachs Salvelinus, and others) migrate for spawning in this time period. A total fish biomass increases a little in the lagoon when saffron cod Eleginus gracilis inhabit it during the winter period. Fish numbers reach maximum values in the bay when the downstream migrants of Pacific salmon leave the rivers and migrate to the sea through the bay. In the second half of May – July, a number of pink and chum fry from the water body can reach a million of individuals. In July-October 1999 and 2000, the most mass species in the bay were pink salmon, big- scaled redfin, saffron cod, threespine stickleback Gasterosteus aculeatus, Amur stickleback Pungitius sinensis, pond smelt Osmerus olidus, Pacific eelpout Zoarces elogatus, flathead sculpin, starry flounder, banded flounder, Sakhalin char Salvelinus leucomaenis, and others (Zemnukhov et al., 2001). By our data (Labay et al., 1999), in June-July 1999, pond smelt (85,7 %) and flathead sculpin (85,7 %) prevailed by frequency from catches obtained with the help of a beach seine. Threespine stickleback Gasterosteus aculeatus, Amur stickleback Pungitius sinensis, and Pacific redfins from the genus Tribolodon (by 71,4 %) were the mass species. Other fish species constituted from 14,3 % to 57,1 %. Some species were absent in catches due to the time period of woks (majority of Pacific salmon) or the place of sampling (fishing was conducted at freshwater or weakly brackish sites). Fish abundance and biomass in the coastal zone ranged widely from 0,01 ind./m2 to 10,84 ind./m2 and from 0,06 g/m2 to 23,66 g/m2, averaged 24,43 ind./m2 and 100,69 g/m2 (Table 2.9.2). Amur stickleback (10,84 ind./m2 and 23,66 g/m2) and pond smelt from genus Hypomesus (5,49 ind./m2 and 20,90 g/m2) had high abundance and biomass. The high biomass was formed by threespine stickleback (16,61 g/m2), flathead sculpin (11,98 g/m2), and Sakhalin char (8,53 g/m2). The rest species did not occur all over the bay area and were found in small numbers.

Table 2.9.2 Fish frequency, abundance and biomass in the Piltun Bay in June-July 1999 from the beach seine catches Abundance, Biomass, Relative Species Frequency, % ind./m2 g/m2 biomass, % Clupea pallasii 14,3 0,07 0,49 0,49 Salvelinus leucomaenis 43,9 0,06 8,53 8,47 Osmerus mordax dentex 14,3 0,03 0,75 0,74 Hypomesus spp. 85,7 5,49 20,90 20,75 Tribolodon spp. 71,4 1,72 11,04 10,96 Rhodeus sericeus 57,1 0,61 0,49 0,49 Carassius auratus gibelio 14,3 0,01 0,06 0,06 Gasterosteus aculeatus 71,4 4,32 16,61 16,50 Pungitius tymensis 42,9 0,07 0,20 0,19 Pungitius sinensis 71,4 10,84 23,66 23,49 Zoarces elongatus 14,3 0,04 1,15 1,14 Megalocottus platycephalus 85,7 0,12 11,98 11,90 Platichthys stellatus 42,9 0,04 2,79 2,77 Liopsetta pinnifasciata 14,3 0,01 2,05 2,04 Total 100,0 23,43 100,69 100,00 55

The bay fishery has a seasonal character. Pacific salmon are captured in summer and autumn during their mass run for spawning, saffron cod and flathead sculpin are captured in winter. Pacific redfins, smelts, Sakhalin char, and flounders are fished as a bycatch. The fishing collective farm “Vostok” is engaged in fishery. Sakhalin char, southern malma, and Pacific redfins are the main object for the amateur fishery. Like other lagoons of the northeastern Sakhalin, Piltun Bay is of great importance for Sakhalin aboriginal people living on the island shores. Their economy is based on fishery in many respects. A patrimonial community of nivkhs «Kekr-vo» is located on the bay shore. In total, 9 persons live in the settlement (information was obtained in the Department of National Policy of Administration of Sakhalin Region). During the anadromous migration of Pacific salmon to the river mouths, the community receives special quota for fishing in the bay. In addition, nivkhs conduct the capture of other fish species in different year seasons.

2.9.1. Main commercial species Among Pacific salmon, pink, chum, masu, and coho salmon enter the rivers flowing into the bay for spawning. Pink (in odd years) and chum salmon have a commercial importance. At the same time their numbers do not reach significant values. Spawning grounds in the bay have, mainly, a “pink salmon” type. A total area of salmon spawning grounds in rivers flowing into the Piltun Bay is 104000 m2 (Table 2.9.3) (Report…, 1957).

Table 2.9.3 Rivers of the Piltun Bay basin and their spawning areas Water catchment Species of Pacific River Length, km Spawning area, m2 area, km2 salmon Sabo 36 587 1000 Pink Kadylanyi 51 440 500 Pink Mukhto 20 90,5 500 Pink Paromay 44 212 2000 Pink Piltun 77 633 100000 Pink Total - 1962,5 104000 -

Pink salmon Under the mean density (140 ind./100 m2) of filling the spawning grounds with pink spawners in the rivers of northeastern Sakhalin, on average, 145,6 thousand fish run through the Piltun Bay during the period of their anadromous migration. At the mean long-term weight of one individual of 1,22 kg, the annual pink biomass constitutes 177,6 t, on average. Based on the data of numbers of the pink downstream migrants leaving the rivers of the northeastern coast, a proportion of fry produced by the watercources flowing into the Piltun Bay was calculated. In odd years about 2,1 million pink fry run through the bay for the sea feeding. In even years – 10,6 million fry. Pink salmon are captured in small numbers by the fishing collective farm “Vostok” (not every year) and patrimonital community «Kekr-vo». The boundaries of the fishery sites are given in Table 2.9.4 (A list of commercial sites…, 1998).

Table 2.9.4 Commercial sites used by companies in the Piltun Bay № of site Boundaries Extension, km User Southern boundary of Astokh Bay – 1 Patrimonial community 1 14 km south of the lighthouse «Kekr-vo» 1 km south of the lighthouse - 3 km Fishing collective farm 2 - north of Cape Agivo «Vostok» 56

Chum salmon This species is not abundant. Fish are captured in small numbers by the patrimonial community “Kekr-vo”. Coho and masu salmon Coho and masu are not abundant, due to that a specialized fishery is not conducted. Saffron cod In the northeastern Sakhalin bays the maximum body length of saffron cod is 54,0 cm, which is the greatest estimate for Sakhalin-Kuril Region (Safronov, 1986). Specimens 18,0-26,0 cm long are the most frequent in commercial catches. The mean body length of saffron cod varied by years in bays. In the Piltun Bay an insignificant change in the mean length was observed to 1994 (from 21,5 cm in 1994 to 24,5 cm in 1988), in 1996-1997 the number of large fish appreciably increased, and the mean length of saffron cod enlarged to 27,4-28,6 cm (Fig. 2.9.1). In December the major part of fish occur in the pre-spawning state. As a rule, the spawned fish make up several percents. By late January – early February the proportion of fish at IV stage of maturity increases to 70,0-80,0 %. A number of the spawned fish does not reach 10,0 %. A great percentage of the pre-spawning saffron cod practically up to February proves the fact that its spawning takes place out of the bay. Evidently, the main part of the spawned fish feed in the open sea.

31

см 29 , 27 АС 25 23 длина 21 19 17

Средняя 15 1988 1990 1992 1994 1996 1998 2000 2002

Годы наблюдений

Fig. 2.9.1. Dynamics of the mean length of saffron cod (cm) in the Piltun Bay, 1988-2002 (except for 1995)

A catch of saffron cod in the bay varied from 168 t (1992) to 40 t (2001), averaged 67,5 t. A number of gear changed from 35 to 73 units, averaged 41 units. Small forms of crustaceans are the most important in the fish diet. Saffron cod captured from the Piltun Bay constitute the maximum numbers compared to the other considered bays. The Piltun Bay proportion constituted from 40,0 to 85,0% of this species total catch in all the bays. In the recent ten-year period the number of gear settled in the bay varied from 37 to 80 units. Flathead sculpin This species is caught from the bay as a “bycatch” during the saffron cod fishing, although its total annual catch exceeds a size of catch of the main commercial species. A sex dimorphism expressed in female body prevailing over a male by the length is common for a flathead sculpin (Volodin, 1999). In our catches the maximum length of flathead sculpins reached 33,0 cm, weight 550 g (Labay et al., 1999). During the period of observations the length of females varied from 14,4 cm to 33,0 cm, averaged 19,0 cm. The length of males varied from 57 11,5 cm to 20,2 cm, averaged 16,4 cm. The weight of female flathead sculpins varied from 58 g to 550 g, averaged 138,8 g. The weight of males varied from 55 g to 138 g, averaged 86,8 g. The base of catches was formed by fish from 15,0 to 18,0 cm long. Specimens at age of 1+ to 6+ were found (Table 2.9.5); second-year fish prevailed (net catches), making up 65,5 % of the total number of fish. The maximum increment was observed at the first and second years of life; the growth rate of the older fish decreased. Flathead sculpin is a dominating species from the fyke net catches in winter period. From 34,2 to 45,4% of the total catch of «sculpin» in the region are captured in the Piltun Bay. A catch of flathead sculpin varied from 525 t (1986) to 200 t (2000). The 1990s practice of processing a multispecies catch in the conditions of northeastern Sakhalin shows that during sorting, only saffron cod and smelt are taken, and flounder and eelpout are named as “sculpin” in the report statistics. In addition, if saffron cod is not a dominant in the catch during lifting a trap, then all the catch is recorded as “sculpin”. By the data of SakhNIRO studies, one can see a percentage composition of “sculpin” in the Piltun Bay (Fig. 2.9.2).

Table 2.9.5 Mean sizes of a flathead sculpin in different age groups from the Piltun Bay in June-July 1999 Age (years) Index Sex 1+ 2+ 3+ 4+ 5+ 6+ female 15,3 18,0 20,9 243 27,5 33,0 Body length, cm male 15,2 17,6 20,2 - - - female 66,2 101,8 162,5 280,5 385,0 550,0 Body weight, g male 65,6 96,2 138,0 - - - Body length, cm 15,2 17,9 20,6 24,3 27,5 33,0 Both sexes Body weight, g 6,6 9,9 15,6 28,1 38,5 55,0

прочие

бельдюга

полосатая камбала

пл.бычок

навага

0 20406080 %

Fig. 2.9.2. A species composition of fishes from catches in the Piltun Bay (in %, by biomass) by the data of 2000

58 2.9.2. Secondary commercial and perspective for fishery species Sakhalin char Salvelinus leucomaenis This species has a potential commercial importance. By our data, the body length of the Piltun Bay Sakhalin char, inhabiting the region of Sabinsky inlet, varied from 15,1 cm to 50,0 cm in catches, and the weight was 39-1400 g (Labay et al., 1999). The age of fish ranged from 1+ to 7+. Two age groups (5+ and 6+) prevailed in net catches, which made up 48,0 and 28,0 %, respectively (Table 2.9.6).

Table 2.9.6 Sakhalin char's length and weight depending on its age from the Piltun Bay in June-July 1999 Age (years) Index min-max (M) 1+ 2+ 4+ 5+ 6+ 7+ Length (33,8-40,0) 15,1-50,0 15,1-16,3 (15,7) 21,4 33,9-44,2 (73,9) 39,3-47,5 (42,8) 50,0 АС, cm 38,0 (40,3) 455,0-780,0 (520,0-960,0) 610,0-1400,0 36,0-1400,0 Weight, g 36,0-40,0 (39,0) 93,0 1200,0 (601,0) 739,0 (894,0) (594,0) Ind. 2 1 8 24 14 1 50 % 4,0 2,0 16,0 48,0 28,0 2,0 100,0

A mature Sakhalin char is a common predator eating, mainly, small fish and Pacific salmon's eggs during their spawning. This species consumes juvenile salmon in great numbers during the pink and chum downstream migration (Savvaitova, 1964; Gritzenko, 1969; Gritzenko et al., 1987; Gritzenko, 2002). Our data prove this. In the summer period, small fish and salmon eggs make up a diet for Sakhalin char in the basin of Piltun Bay (a region of Sabinsky inlet) as well. A total of 6 fish species were recorded in the composition of its food bolus (Table 2.9.7). 0 The mean index of stomach fullness was 29,64 /000 over the region. Amur stickleback Pungitius 0 sinensis (a dominant by abundance) constituted 189 /000 in stomachs of Sakhalin char, lake 0 0 minnow and salmon eggs constituted 27 /000 and 4 /000, respectively. By frequency, Amur stickleback was the most common species (91,3 %). The rest species occurred sporadically. A size composition of food organisms varied from 0,5 to 15,0 cm. The analysis of species composition of the food bolus showed that the base of Sakhalin char diet in the study region was formed by organisms of size classes from 5,0 to 10,0 cm. One of the mass fish species in the region, pond smelt, occurred sporadically in the diet (4,3%), and Amur stickleback was the most frequent in the Sakhalin char stomachs (91,3%). Sakhalin char is an object for amateur fishery.

Table 2.9.7 A content composition of alimentaly canals of Sakhalin char from the Piltun Bay in June-July 1999 Mean Mean Index of Relative Index of Food object Frequency, % abundance, biomass, fullness, 0 biomass, % density ind. g /000 Amur Dominant 91,3 8,0 15,18 189 80,9 7390,296 stickleback Sakhalin 17,4 0,2 2,48 27 13,2 230,244 Typical lake minnow Salmon eggs 13,0 0,8 0,30 4 1,6 20,867 Threespine 4,3 0,1 0,40 3 2,1 9,173 stickleback Secondary Pond smelts 4,3 0,0 0,28 4 1,5 6,452 Sakhalin 4,3 0,0 0,12 1 0,6 2,722 stickleback Total 6 - 9,2 18,75 229,4 100,0 -

59 Pond smelts Hypomesus This species has a potential commercial importance. The length of pond smelts (Fig. 2.9.3) from the northern part of Piltun Bay varied from 3,1 to 8,5 cm, averaged 5,75 cm (Labay et al., 1999). Banded flounder Liopsetta pinnifaciatus This species is caught from the bay as a “bycatch” during fishing the other fish species. In our catches the length of fish varied from 6,2 to 31,4 cm, averaged 21,4 cm, weight from 5 to 572 g, averaged 178 g (Labay et al., 1999). Fish gonads were at I-Ш stages of maturity. A banded flounder constantly presents in catches during the winter fishing of saffron cod and «sculpin». Starry flounder This species is caught from the bay as a “bycatch” during fishing the other fish species. In our catches the length of starry flounder from the Piltun Bay varied from 5,0 cm to 27,3 cm, averaged 13,3 cm, weight from 3,3 to 350,0 g, averaged 176,6 g (Labay et al., 1999). This species is an object for amateur fishery.

40 30

% 20 10 0 456789 Длина, см

Fig. 2.9.3 . Distribution of pond smelts by lengths АС in the northern part of Piltun Bay in June-July 1999 (n = 162)

2.9.3. Mass non-commercial species Threespine stickleback Gasterosteus aculeatus This species reaches great numbers in the bay, but has not any commercial importance. Mainly, it is used in the diet of the other fish species or their juvenils (pond smelts, juvenile Pacific redfins and others). Threespine stickleback often eat eggs of the phytophilous fish during their spawning. The length of threespine stickleback (Fig. 2.9.4) from the Piltun Bay varied from 5,0 to 7,9 cm, averaged 6,94 cm (Labay et al., 1999). A spawning process of threespine stickleback was observed during the study period, which occurred under the water temperature of 21-23 °С. The beginning of mass spawning was recorded on 30 June, and its peak on 2 July. 60

40 30

% 20 10 0 5,5 6,0 6,5 7,0 7,5 8,0 Длина, см

Fig. 2.9.4. Distribution of threespine stickleback by lengths АD in the Piltun Bay in June-July 1999 (n = 429)

Amur stickleback Pungitius sinensis This species has not any commercial importance in the bay. The length of fish in the Piltun Bay varied from 3,1 to 9,6 cm (Fig. 2.9.5), averaged 7,53 cm (Labay et al., 1999). A ratio between females and males was 3:1 on spawning grounds. The majority of sticklebacks had ripe gonads. The spawned fish constituted 23,5%.

20 15

% 10 5 0 45678910 Длина, см

Fig. 2.9.5. Distribution of Amur stickleback by lengths АD in the Piltun Bay in June-July 1999 (n = 149)

Thus, the Piltun Bay has a commercial importance. The main commercial fish species are as follows: saffron cod, flathead sculpin, pink salmon (odd years). Banded flounder is captured as a bycatch. The greatest number of saffron cod (to 85 %) is caught in the Piltun Bay compared to other lagoons of northeastern Sakhalin. In summer-autumn period the herring spawning and feeding take place in the Piltun Bay. The migratory ways of adult Pacific salmon and their fry pass through the bay area to the mouths of spawning rivers. Pink salmon is the most abundant. In the freshened regions of the bay (Sabinsky inlet) the most mass fish species in the summer-autumn period are as follows: threespine and Amur sticklebacks, pond smelts, big- scaled redfin, saffron cod, flathead sculpin, starry and banded flounders. Pond smelt and flathead sculpin were dominants by frequency (by 85,7 %). Fish abundance and biomass in the coastal zone varied from 0,01 to 10,84 ind./m2 and from 0,06 to 23,66 g/m2, respectively. Amur stickleback was the dominant species by abundance and biomass (10,9 ind./m2 and 23,66 g/m2).

61 3. CHAIVO BAY

3.1. General physic-geographic characteristics of the Chaivo Bay

The Chaivo Bay is located between 52º17´ and 52º40´ N. Its extension is about 42 km, width to 6 km, area 126.4 km2. A bathymetric scheme of the Chaivo Bay is presented in Fig. 7.1.1. As one can see from this scheme, the bay is a common coastal semi-closed lagoon separated from the sea by two low-lying spits. A southern spit is short; its extension makes up about 8.5 km, width 0.3-1.7 km. The sand hills 3-7 m high occur on the spit; hills’ slopes are flat and grown with alder-trees and cedar forest. The extension of the northern spit is about 35 km; its width varies from 0.4 km in the narrowest part to 4 km in the widest part. The northern bar is covered with a lot of fresh-water lakes with 1-2 m depths. The banks of lakes are covered with grass and bushes. The bay is joined with a sea by the Kleye Strait occurring between the capes Kambrulbash on the southern spit and Ayash on the northern spit. The strait extension is about 4.5 km; depths on the fairway are from 3.5 to 12-16 m. By the morphogenetic type, the Chaivo Bay occupies an intermediate position between a common lagoon and a lagoon-estuary. On the one hand, the erosive narrows in the mouths of rivers flowing into the bay are expressed rather weakly; on the other hand, the lagoon basin is weakly expressed too. The main fairway of the Chaivo Bay passes to the north of the Kleye Strait along the western shore of the northern spit and turns round the Soniga Island being divided into two branches: one of them goes to the north (to the Irkimibu Island), another branch turns to the south. The branches of the main fairway to the west of the Kleye Strait are divided into two flows directed to the south (Cape Ulvo) and to the north (Soniga Island). The depths of the main fairway are from 2.0 to 4.0 m; the depths of its branches are 2.0-2.5 m. Due to the relative narrowness, the basin of the bay is weakly expressed. The bottom is like a plain with depths less than 1.5 m. A major part of the bottom is being dried during the ebb. The Chaivo Bay shores are low-lying; only on the western shore there are not any tall sandy steeps in the central part of the bay. The eastern shore of the bay is mainly sandy. The southern, northern, and major parts of the western coasts are covered with pitbogs, swamped here and there. A hydrographic net is well developed in the southern and western parts of the bay. The Evay River delta and a channel joining the bays Chaivo and Nyisky are located in the south. In the west a lot of brooks and rivers flow into the bay. The rivers Askasai, Val, Khanduza, Bolshoy and Maliy Goromai, and Ossoi are the largest among them. The mouths of rivers and brooks from the western coast are weakly branched and look like the swamped plains. Small brooks flow into the bay in the north. Tidal fluctuations of a sea level affect greatly the formation of the lagoon hydrodynamics regime. The existence of a short and deep channel and long fairways provides a penetration of the tidal wave practically all over the bay. In the study region the tidal fluctuations have a daily character, that is, one high and one low tide are being observed during 24 hours. A mean estimate of the daily tide at the entrance of the Chaivo Bay makes up about 0.9 m, the maximum estimate 1.9 m. During the tidal waves penetration into the bay along the fairway, a decrease in their amplitudes and increase in their phases take place due to the diffraction and increase in the influence of the bottom and lateral friction. The tidal wave penetration into the lagoon is accompanied with the rise of strong tidal streamline currents. These currents reach the maximum values on the main fairway, directly at the bay outlet. By the measuring data, their mean values constitute 0.4-0.7 m/sec, and maximum may exceed 2.2 m/sec. The influence of the tidal currents upon the hydrodynamics conditions of the bay is localized in the region of the channel and fairways. Moving off them, the periodic currents are rapidly weakened and become hardly noticeable in the shallow zones. Besides the tidal phenomena, a sea influence on the hydrodynamics regime of the Chaivo Bay is reflected in stormy raising of the water level. The raising origination is caused by

СахНИРО Отчет по договору Y-00571 62 meteorological phenomenon: the influence of atmospheric pressure and wind on the sea surface. The greatest raisings are observed in October-November and February-March, that is connected with passing the deep cyclones above the Okhotsk Sea. In this period the level raise may reach 0.5-1.0 m. The effect of raising the water level is usually strengthened by the influence of the heavy sea. As a rule, a duration of raising makes up more than 24 hours. During this time period a great volume of seawater enters the bay caused by the activity of the pressing wind. After stopping the activity of factors provoking raisings, the accumulated water mass flows to the sea out of the bay grasping solid material. The active dynamics in the strait causes a constant change in the outlet of the Chaivo Bay. A southern shore of the Kleye Strait is being eroded shifting to the south with the mean velocity of 20 m/year. Simultaneously, the inwash of the northern spit is going approximately with the same velocity. Along with the change in channel position, the fairways’ positions change greatly too. In the Chaivo Bay the tidal phenomena and stormy raisings of the water level influence significantly upon the position of fairways. The affect of a river run-off occurs, mainly, in the southern part of the bay, where the large rivers Evay, Vat, and Askasai flow. The affect of the river run-off is the greatest during a spring flood, the peak of which occurs in mid-May. In this time period the mean estimates of the water rise in the Val River reach 1.7-2.2 m. A period of the spring flood continues, as a rule, since late April to mid-June. About 30 % of the annual river run-off volume and up to 60 % of the annual alluvium run-off arrive to the bay. In autumn (usually in August-October), rainy floods take place, which are accompanied by the raise of water level up to 1.2 m. The duration of rainy floods makes up, as a rule, not more than 9-12 days. In the rest time (including summer and winter low water levels) the water level in rivers is rather stable, and the volume of water flowing to the bay practically remains invariable. The mean annual volume of water flowing out of the Val River constitutes about 720 million m3 a year. The annual alluvium run-off for rivers flowing into the Chaivo Bay was not estimated. For the Dagi River, flowing approximately in the same conditions, the annual alluvium run-off constitutes 7.6 thousand t/year under the mean annual water run-off 345 million m3/year.

3.2. Hydrology and hydrochemistry of the Chaivo Bay

3.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data The archive data on the Chaivo Bay are presented by the materials of monitoring studies of SakhNIRO in lagoons and coastal zone of the northeastern Sakhalin in 1995-1996 (Samatov et al., 1997), and results of researches conducted by the joint scientific expedition SakhNIRO – “Ecological Company of Sakhalin” in June-July 1999 (Ecological studies of the bays…, 2001). The data on hydrologo-hydrochemical regime, particle-size composition of bottom sediments and pollutant contents in them practically are absent in the literary. During the surveys conducted in June 1996, a total of 6 stations embracing the southwestern and central parts of the bay, and the channel had been performed; hydrochemical characteristics were determined and a level of the bay pollution was estimated. In June-July 1999, a total of 19 hydrochemical stations were performed, and a particle- size composition of BS was studied; at 15 stations BS were examined for the occurrence of heavy metals; at 7 stations BS were examined for the occurrence of other pollutants. Methods of sampling and studying are given in the chapter “Archive data of the Piltun Bay study”. A temperature regime of the lagoon is determined by the seawater flow through the channels, radiation warming, and in-shore run-off. In the summer period, the lowest water temperatures have been recorded in the near-strait part of the bay, where the thermal regime is determined by the cold seawater entrance. During the survey, a surface water temperature in the region of Kleye Strait and in the central part of the bay was 17-18 °С, in the northern part of the bay 17-19 °С, and in the southern part of the bay 17-20 °С. A vertical structure of the temperature field was characterized by the temperature lowering from the surface to the

СахНИРО Отчет по договору Y-00571 63 bottom in the Kleye Strait (5-6 °С lesser), in the central deep-water part of the bay approximately 3 °С. While moving away from the fairways, temperature differences reduced rapidly to 1-2 °С, practically disappearing on the shallows. A salinity regime of the bay water was determined by the joint influence of sea tides and river run-off. The water with more than 20 ‰ of salinity occupies practically all the central part of the bay; differences in salinity distribution at the surface and near the bottom are not significant. In the southeastern and northern parts of the bay, salinity declines to 4-10 ‰. There, the in-shore run-off affects the salt regime. A vertical salinity distribution in the Chaivo Bay is rather homogeneous: differences between salinity values at the surface and near the bottom do not exceed 1-3 ‰. This is promoted by the active water dynamics and relative shoal of the bay providing a good confusion (Ecological studies…, 2001). pH value of the bay water varied within 7.60 – 8.65 in 1996, water saturation with oxygen from 55.0 to 118.0 %. Concentrations of biogenic elements were low enough; estimates for nitrates and ammonium ions in major cases were lower than a threshold of detectability of the method. Nitrite contents in the bay water varied from 0.00 to 7.86 mkg/dm3, silicon from 480.5 to 1550.0 mkg/dm3. A content of dissolved oxygen varied, mainly, within 8.5-11.0 mg/dm3 by the 1999 data. The minimum of oxygen concentrations (6.3 mg/dm3) was recorded at the station near the base of the southern spit of the bay. The maximum concentration (13.0 mg/dm3) was observed not far from the Kleye Strait. A vertical distribution of dissolved oxygen in the region of fairways was characterized by a decline in concentrations from the surface to the bottom layers (0.1 - 0.7 mg/dm3 less). A content of suspended matters varied within 17.1 – 35.9 mg/dm3 in 1999; the maximum concentration was recorded in the mouth of Val River.

3.2.2. Results of hydrologic-hydrochemical researches in 2002 Results of hydrologic-hydrochemical analysis of samples from the Chaivo Bay are given in Appendix 3.2.1. Some statistic characteristics of the determined parameters are reflected in Table 3.2.1. As one can see from the presented data (Appendix 3.2.1), the bay depths at several stations let us to make sampling both from the surface and near-bottom horizons.

Table 3.2.1 Some statistic characteristics of the determined ingredients from the Chaivo Bay in September 2002 Ingredients Xav Xmax Xmin Depth, m * 5.0 0.4 Temperature, ºС 8.9 10.0 5.4 Salinity, ‰ 17.6 28.5 2.6 pН value 8.23 8.74 7.49 Dissolved oxygen, mg/dm3 9.67 11.00 8.43 Nitrite nitrogen, mkg/dm3 0.8 2.6 < 0.5 Nitrate nitrogen, mkg/dm3 < 5.0 9.0 < 5.0 Phosphorus (orthophosphates), mkg/dm3 37.3 76.5 12.0 Silicon, mkg/dm3 716.5 1699.0 1.3 Mass concentration of petroleum hydrocarbons, < 0.005 < 0.005 < 0.005 mg/dm3 Suspended matters, mg/dm3 20.04 49.70 10.35 Chlorophyll а, mkg/dm3 2.74 4.22 1.84 * insufficient data for a statistic processing

СахНИРО Отчет по договору Y-00571 64 A temperature distribution over the study area and by the horizons was uneven. The water temperature lowered gradually from the north to the south. The maximum temperature was recorded at the very north station (station 1-10 ºС), minimum at the very south station (station 9 – 5.4 ºС). In the center of the bay a gradual decrease in water temperature was observed (stations 4, 8 – 9.6, 7.9 ºС, respectively). The mean water temperature in samples from the Chaivo Bay was 8.9 ºС. The maximum salinity was recorded in the channel connecting the bay with the sea (station 6 – 28.5 ‰), minimum at station (9) being the remotest from the channel in the southern part of the bay – 2.6 ‰. The mean salinity estimate was 17.6 ‰. Temperature and salinity estimates in surface and near-bottom horizons practically do not differ, probably, due to the intensive confusion of water masses. The mean pH value of the water samples was 8.23. Seawaters influenced greatly, and terrigenous and river run-offs less on the distribution of pH over the bay area. Thus, the minimum pH values (7.49, 7.95) were observed at stations located near the river mouths (st. 9, 1); a gradual increase in pH value was observed as far as approaching to the channel. The maximum estimate was recorded at station 6 (a mid-channel) – 8.74. Due to the depth of sampling, pH slightly decreased from surface to near-bottom horizons (Appendix 3.2.1). The dissolved oxygen concentration in water samples was high enough and varied from 8.43 (a near-bottom horizon, st. 3) to 11.00 mg/dm3 (st. 7). The mean concentration estimate was 9.67 mg/dm3. At all deep-water stations an insignificant decrease in oxygen concentration from the surface to near-bottom horizons was observed, evidently, due to the discharge of bottom organic sediments for oxidation. The nitrite nitrogen concentration was 0.8 mkg/dm3, on average. The maximum estimate (2.6 mkg/dm3) was recorded in the water sample at station 6; as far as removing from the channel, the nitrite concentration in samples gradually lowered. At stations (1, 2, 7, 8, 9) nitrites were not found or their estimates were close to a threshold detectability of the method (0.5 mkg/dm3). The nitrate nitrogen concentrations were minimal in major cases and occurred below a threshold detectability of the method (5.0 mkg/dm3). Only at several stations (3, 4, 6), located close to the channel, the nitrites were found, which contents at each station were 9.0 mkg/dm3. Phosphorus and silicon distribution patterns over the bay area were uneven, their concentrations ranged widely. A content of phosphorus varied from 12.0 (st. 9) to 76.5 mkg/dm3 (st. 5, a near-bottom horizon). The mean content of phosphorus was 37.3 mkg/dm3. Its maximum concentrations were found at the deep-water stations in the center of the bay, minimum at the very edge stations in the southern and northern parts of the bay. The mean content of silicon was 716.5 mkg/dm3. Its maximum concentrations were recorded in water samples at stations located in a zone of influence of the terrigenous run-off (rivers Evay, Askasai, Val) – from 1211.2 to 1699.0 mkg/dm3, minimum at station 5 – 1.3 mkg/dm3. Examinations of water samples from the Chaivo Bay for petroleum hydrocarbon contents did not give positive results; all estimates occurred below a threshold detectability of the method (< 0.005 mg/dm3). The suspended matter concentrations ranged from 10.45 (st. 8) to 49.70 mg/dm3 (st. 9). The averaged sample showed a presence of suspended matters in the concentration of 20.04 mg/dm3. The mean chlorophyll concentration in samples was 2.74 mkg/dm3. The maximum content (4.22 mkg/dm3) was found in sample at station 1, minimum (1.84 mkg/dm3) in the surface horizon of station 5. On the whole, a distribution of chlorophyll a concentration over the study area was rather even. An increase in concentrations from surface to near-bottom horizons was observed for the distribution patterns of suspended matters and chlorophyll a by depths. Thus, the greatest influence upon the distribution pattern of the main determined components was made by seawaters, and the terrigenous run-off affected less. When distributing hydrochemical parameters by depths, an insignificant lowering of the dissolved oxygen concentration and increase in concentration of suspended matters and chlorophyll a from the

СахНИРО Отчет по договору Y-00571 65 surface to near-bottom horizons were observed. Estimates of concentrations of all the determined ingredients were within the standard or much lower the tolerance limit concentrations (List of fisheries standards …, 1999); often the concentrations of determined parameters were below a threshold detectability of the method.

3.3. Particle-size composition of bottom sediments in the Chaivo Bay

As a result of the particle-size analysis of BS in 1999, a total of 6 genetic aggregates of fractions of bottom sediments: pebble, gravel (particle size more than 2 mm); graveled and coarse sand (2-0.5 mm); medium sand (0.5-0.25 mm); fine sand (0.25-0.1 mm); pulverulent sand (0.1-0.05 mm); dust, clay (less than 0.05 mm) were found. A composition of the bay bottom sediments was determined, to a great extent, by the location of sampling stations relatively to the zones of hydrodynamics activity. Sediments of a gravel-pebble fraction in the Chaivo Bay occurred in very small numbers on the fairway near the Soniga Island and along the coast in the capes region. The maximum content of the coarse-fragmental fractions (33.5 %) was recorded at the in-shore stations near the southern extremity of Irkamibu Island. Fractions of graveled and coarse sand were distributed rather even (4 – 8 %); the maximum of their content was recorded on the fairway near the northern extremity of Soniga Island. Fractions of medium and fine sand (14 – 20 % and 25 – 40 %, respectively) were recorded on the fairways and near the shore. Particles of 0.1 – 0.05 mm prevailed in the southern part of the bay, where their contents in samples reached 20 %. Fractions of 0.05 mm prevailed in the southern part of the bay, in the stagnant zone along the western coast, and in the northern codened part and made up 40 – 60 % of the sample composition. In a zone of fairways the percentage content of aleuro-pelite fractions declined to 15 – 25 %. The sand domination was revealed to be common for the in- shore Chaivo stations by BS types: within the main fairway – prevailing the fine and pulverulent sand types; on the fairway branches – prevailing the loam and clay types. Directly in the bay the dominant type of bottom sediments was clay and loam, along the western coast – silts.

3.4. Content of pollutants in the Chaivo Bay

3.4.1. Content of pollutants in bottom sediments by the archive and literary data Petroleum hydrocarbons A content of petroleum hydrocarbons (PHC) in bottom sediments varied from 70.0 to 120.0 mkg/g in June 1996, and in major cases significantly declined to 10.0 mkg/g in August. The maximum concentration of petroleum resinous matters in June was recorded in the central part of the bay upper the Soniga Island – 29.0 mkg/g. By the end of August a portion of resinous matters declined significantly, and their concentrations in major cases constituted 0.1 mkg/g. Below we give the mean concentrations of PHC in the bay bottom sediments in June and August 1996 (Table 3.4.1).

Table 3.4.1 Mean content of PHC in the Chaivo Bay bottom sediments in June and August 1996 (mkg/g) Study period Non-volatile Resinous matters Total content hydrocarbons June 65.0 30.0 95.0 August 20.0 6.0 30.0

A content of PAHC varied from 0.02 to 0.34 mkg/g, the mean estimate was 0.20 mkg/g. In 1999, a content of petroleum products varied from 0.0 to 0.5 mkg/g, the mean estimate was 0.13 mkg/g. The maximum estimates were observed in the northern part of the

СахНИРО Отчет по договору Y-00571 66 bay near the Irkimibu Island and timed to the stagnant zones. A positive relationship of petroleum product concentrations with the content of thin fractions 0.05 mm size and with the concentrations of organic hydrocarbon (Ecological studies of the bays …, 2001) was revealed; this indicates the predominantly natural character of sources of the petroleum products inflow to the bay. Metals In June 1996, the bottom sediment sampling was conducted only at two stations. Despite the close location of these stations, significant differences between the concentrations of iron (300 and 20500 mkg/g), manganese (64 and 195 mkg/g), and zinc (17 and 63 mkg/g) were observed. In August, a great scatter of manganese and iron estimates occurred, and the variability of zinc concentrations decreased. The level of element content became significantly lower; this was associated with seasonal changes in the character and volume of the terrigenous run-off. The mean estimates of metals in the bay bottom sediments are reflected in Table 3.4.2.

Table 3.4.2 A gross content of metals (mkg/g of the dry weight) in the Chaivo Bay bottom sediments in June and August 1996 Determined metal Concentration, mkg/g of the dry weight June August range mean range mean Al, % 4.97 – 6.17 5.57 2.20 – 3.70 2.80 Fe, % 0.93 – 2.05 1.49 0.23 – 0.46 0.33 Mn 64 – 195 130 16 - 57 35 Ba 600 – 770 685 420 - 600 520 Zn 17.0 – 63.0 40.0 5.0 – 8.6 6.5 Cr 47.0 – 56.0 52.0 52.0 – 63.0 57.8 Ni 37 – 47 42 33.0 – 35.0 34.2 Cu 19.0 19.0 16.0 – 17.0 16.6 Co 2.5 – 5.1 3.8 2.0 – 2.2 2.1 Pb 19.0 – 20.0 19.0 10.0 – 15.0 12.2 As 6.3 – 8.6 7.5 3.0 – 4.8 3.9

In 1999, the fact of connection between the microelement distribution in bottom sediments and that of aleuro-pelite fraction (less than 0.05 mm) was revealed. Concentrations of major metals were higher in the stagnant zones along the southwestern and western coasts of the bay. The minimum of concentrations occurred in the region of the main fairway and coastal sites with sandy grounds. The mean concentrations of metals in the bay bottom sediments are presented in Table 3.4.3. Correlation dependence between the contents of the metal acid-dissolved forms and particle-size composition of bottom sediments was revealed; this proves a sorption ability of bottom sediments as the main factor determining the level of metal concentrations. By the microelement content, bottom sediments are distributed in the following order: silt>clay>loam>sand. Table 3.4.4 shows the mean concentrations of microelements in different types of the bay bottom sediments.

СахНИРО Отчет по договору Y-00571 67 Table 3.4.3 Mean contents of the metal acid-dissolved forms (mkg/g of the dry weight) in the Chaivo Bay bottom sediments in June 1999 Determined metal Concentration, mkg/g Al, % 7.4 Fe, % 8.6 Mn 91.1 Cd less than 0.05 Zn 24.2 Cr 20.5 Ni 16.6 Cu 6.9 Co 3.3 Pb 3.6 Hg 0.015

Table 3.4.4 Mean contents of the metal acid-dissolved forms (mkg/g of the dry weight) in different types of the Chaivo Bay bottom sediments in June 1999 Type of Concentration, mkg/g sediment Fe, % Al, % Mn Zn V Cr Ni Cu Pb Co Cd Hg Silt 14.6 17.4 199 58.8 55 34.929.5 13 8.8 6.3 <0.050.025 Clay 12.7 12.2 136 27.5 16.7 32.9 25.8 9.3 4.5 4.5 <0.050.010 Loam 7.0 3.4 52.121.7 - 14.313.0 5.1 1.7 2.5 <0.050.010 Sand 3.0 1.0 15.74.22 - 4.2 3.252.9 0.24 0.9 <0.050.007

Phenols In 1996, a total of 2 samples of bottom sediments were analyzed; concentrations constituted 1.4 and 4.4 mkg/g of the dry weight, respectively. Chlororganic pesticides and polychlorinated biphenyls In June 1996, alpha- and gamma-isomers HCCH, p,p-DDE and p,p-DDT were found in the bottom sediment samples. A total number of chlororganic pesticides (COP) were 0.24 and 1.24 ng/g of the dry weight, respectively. In August the mean content was 0.13 ng/g of dry weight, maximum estimate of the total COP was observed along the western shore near the railway (0.4 ng/g). Polychlorinated biphenyls (PCB) were not found in the bay bottom sediments (BS). By the results of the 1999 survey, COPs were found in bottom sediments of 5 stations. Three compounds of five being determined were found on the bay area. γ-HCCH and DDT were not found in samples, α-HCCH was once recorded, DDE – two times, DDD – four times. The mean pesticide content in the bay BS was 1.20 ± 0.92 ng/g. The maximum concentration of COP (2.1 ng/g) was found in the central part of the bay, not far from the Kleye Strait. High concentrations (1.7 - 2.0 ng/g) were recorded in the northern part of the bay. A quantitative domination of DDD and DDE (DDT metabolites) in samples under the absence of the initial form is evidence of the processes of pesticide destruction. Organic carbon By the results of the 1999 study, contents of organic carbon varied from 0.0 to 10.0 %. The mean concentration was 2.9 ± 2.7 %, coefficient of variation 94.6 %. Stagnant zones along the western coast of the bay were found to be distinguished during the distribution of organic carbon in the grounds over the area, where its concentrations increased to 5.0 %. The maximum estimates were recorded in the silty sediments. Formation of zones with the higher organic contents in the bay was supposed to be connected with the increase in dispersibility of bottom sediments. In the rest part of the bay the organic portion in bottom sediments varied within 1.5 – СахНИРО Отчет по договору Y-00571 68 3.5 %. A high correlation dependence was found between the content of organic carbon, composition of thin (less than 0.05 mm) fractions of BS, and concentration of petroleum products; based on this, the region is characterized as a pure one, and the absence of anthropogenic sources of organic inflow is being proved (Ecological studies of the bays…, 2001).

3.4.2. Content of pollutants in biota Hydrocarbons in Zostera A single observation was conducted. On average, a level of accumulation of general hydrocarbons in the bay was 2.6 mg/g of the wet weight, of which 23 % were made up by PHC. A concentration of PAHC was 1.4 mg/100 g of the wet weight. Metals in Zostera Studies were conducted at 3 stations. The found concentrations varied as follows: from 2.3 to 3.1 ng/n of the wet weight for zinc, from 1.00 to 1.30 ng/g for copper, from 0.007 to 0.080 ng/g for mercury, from 0.22 to 0.29 ng/g for lead, from 0.28 to 0.79 for cadmium, and from 1.8 to 2.1 ng/g for chromium. Chlororganic pesticides and polychlorinated biphenyls in Zostera One species of pesticides (α-HCCH) was found. Its concentration was from 0.05 to 0.08 ng/n of the wet weight.

3.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 Results of analysis of the bottom sediment samples for the content of petroleum products in the Chaivo Bay are given in Table 3.4.5.

Table 3.4.5 A summarized concentration of petroleum products in samples of bottom sediments and results of the analysis quality control № Concentration of Mean divergence of Extraction of ersatz standard, % st. petroleum products, duplicates, % mkg/g Mean Rel. st. deviation 1 15.2 20 83 21 2 6.04 3 15.5 4 22.1 5 26.5 6 1.01 7 8.54 8 4.44 9 0.95

As one can see from the given Table, the estimates of petroleum hydrocarbons (PHC) from the bottom sediment samples of the Chaivo Bay are distributed very unevenly and varied widely from 0.95 to 26.5 mkg/g. The maximum estimates of PHC concentrations were observed at stations 4 and 5 (22.1, 26.5 mkg/g, respectively), minimum at stations 6 and 9 (0.95, 1.01 mkg/g, respectively). The definite regularities for the petroleum products distribution in bottom sediments were not found, but we should note the higher level of PHC accumulation in bottom sediments of the deep-water stations 3, 4, and 5 (15.5 – 26.5 mkg/g), and at station 1 (15.2 mkg/g); at the rest stations the content of petroleum products in bottom sediments did not exceed 8.54 mkg/g. The analysis of results of the quality control has shown that % of the duplicate divergence and % of the extraction of ersatz standard did not exceed the tolerance criteria of quality. СахНИРО Отчет по договору Y-00571 69 3.5. Microbiological researches in the Chaivo Bay

When studying a structure of the water microbe cenosis in the Chaivo Bay in September 1998, a total of 3 water samples were collected (conventionally named stations 1, 2, 3). Numbers of the following physiological groups of aerobic heterotrophic colony-forming microorganisms were determined in water: saprophyte heterotrophic bacteria, growing on RPA, marine heterotrophic organisms, developing under the different water salinity (environment of Yoshimitsu-Kimura); petroleum-oxidizing, phenol-resistant, and metal-resistant; destructors of bipolymers of amylolytic, proteolytic, and lipolytic bacteria. A content of saprophyte heterotrophic bacteria in the examined water samples from the Chaivo Bay stations was 105 – 106 cell/ml. A number of marine heterotrophic bacteria adapted to the salinity gradient was the same in all samples - 106 cell/ml. Indices of petroleum-oxidizing microorganisms were high enough and constituted 105-106 cell/ml; a number of phenol-resistant microorganisms ranged within 102-104 cell/ml (Table 3.5.1). Table 3.5.1 Indices of numbers of the physiological groups from the aerobic saprotrophic microorganism community in seawater of the Chaivo Bay studied stations, (cell/ml) Physiological groups of Chaivo Bay microorganisms st.1 st.2 st.3 Marine saprotrophic organisms 106 106 106 Heterotrophic organisms 106 – 105 Phenol destructors 102 104 104 Petroleum destructors 105 106 106

The number of amylolytic bacteria was determined only in one water sample. It was 74.04% of the heterotrophic organism numbers. The Chaivo Bay is rich for its water flora, which is a supplier of organic matters with the carbohydrate chain, due to which a development of amylolytic microorganisms takes place. The high number of this physiological group indicates the presence of such matters in the bay water in great numbers. Proteolytic bacteria constituted from 0.91 to 21.25% of the total number of heterotrophic organisms. Indices of the number of lipolytic bacteria were the lowest. Their portion in the general structure of the microbe community did not exceed 12.1% (Table 3.5.2). Table 3.5.2 Relative numbers of some physiological groups from the aerobic saprotrophic microorganism community in 1 ml of seawater from the Chaivo Bay stations in 1998 (%) Physiological groups of Chaivo Bay microorganisms st. 1 st. 2 st. 3 Heterotrophic 100 100 100 Proteolytic 0,91 21,25 9,89 Lipolytic 8,57 7,08 12,2 Amylolytic –* – 74,07 Cd-resistant 0** 0 0 Pb- resistant 12,8 0,1 26,7 Co- resistant 3,4 0 4,15 Cu- resistant 4,85 0,14 3,26 Ni- resistant 40 0,12 21,48 Zn- resistant 0,045 0 0 Fe- resistant 17,7 0.88 6,67 *(–) - indefinite **(0) – absence of growth

СахНИРО Отчет по договору Y-00571 70

Cd-resistant microorganisms were not found in the examined water samples. The estimates of Zn- resistant microorganisms were minimal. The proportion of Ni- resistant forms was high – up to 40 %. The high indices of numbers were from individual samples of Pb- and Fe- resistant microorganisms; this reflects the geochemical peculiarities of the region.

3.6. Phytoplankton of the Chaivo Bay

3.6.1. Description of phytoplankton by the archive and literary data By the materials of a joint expedition of SakhNIRO and ECS (Sakhalin Ecological Company) in July 1999, a total of 125 species and intraspecific microalgal taxons have been found at 4 stations of the Chaivo Bay. Diatom algae division was distinguished by its richness of species composition (69 % of the total number of species). The second place by the number of species was occupied by green (11 %) and dinoflagellate algae (10 %). A portion of the rest divisions (bluegreen, cryptophytes, euglenic) was insignificant in the formation of species composition. Numbers in the bay during this period varied within 157,625 – 983,584 thousand cell/l, averaged 500 thousand cell/l, biomass 214,02-504,41 mg/m3, averaged 301,4 mg/m3. The maximum estimates of algae abundance were recorded in the northern part of the bay, where the green algae Ankistrodesmus convolutes vegetated greatly, minimum at the near-mouth site of Val River. The minimum biomass estimates were recorded there too. The maximum biomass was recorded at the site located nearby the outlet of the bay into the sea, where the cryptophyte alga Cryptomonas erosa dominated (Ecological studies…, 2001).

3.6.2. Characteristic of phytoplankton in 2002 A floristic composition of the Chaivo Bay was formed in late September, 2002 by 117 microalgal species belonging to 7 divisions: diatoms Bacillariophyta (100 species and intraspecific taxons), cryptomonades Cryptophyta (5), bluegreen Cyanophyta (4), dinoflagellates Dinophyta (3), euglenic Euglenophyta (3), chrysophytes Chrysophyta (1), and green Chlorophyta (1) (Appendix 2.6.1). Diatoms Cocconeis pediculus (Ehr.), Melosira varians Ag, Synedra tabulata (Ag.) Kutz.were found almost everywhere (83 % of frequency). The base of phytoplankton community was formed by freshwater and freshwater- brackish species, making up together 62 % of the total microalgae number. Brackish-marine (16 %) and marine species (12 %) contributed some portions into the formation of species composition too. The greatest number of these species was recorded at the outlet of the bay into the sea, as it was expected. Hydrologic peculiarities of the bay, including the tidal currents, temperature background, and others, determined heterogeneity of the spatial phytoplankton distribution. The analysis of quantitative phytoplankton characteristics let us to divide conditionally the bay into two regions: northern (north of the outlet from the bay to the sea) and southern (south of the outlet from the bay to the sea). Thus, the maximum estimates of abundance (122,258 – 217,141 thousand cell/l) and biomass (228,675-596,3 mg/m3) were recorded in the less warmed southern part of the bay, that was caused by the predominant developing of the diatom flora (96-100 % of the total abundance, 99-100 % of the total biomass) compared to the northern part (Appendix 2.6.2). The abundant vegetation of the freshwater-brackish diatom Melosira varians (41-45 % of the total abundance, 41-52 % of the total biomass) was observed at the more freshened sites of this part of the study area. The northern part of the bay, in the contrast, was characterized by the lower estimates of quantitative indices: the maximum estimates of abundance there were 41,039 – 91,714 thousand cell/l, biomass 42,877–224,324 mg/m3. Along with diatom algae (47-79 % of the total abundance, 73-95 % of the total biomass), which prevailed everywhere, the cryptophyte algae from the genus Plagioselmis (21-29 % of the total abundance) dominated at the very

СахНИРО Отчет по договору Y-00571 71 northern site. Among species-dominants, the diatom Cocconeis scutellum Ehr.(23-37 % of the total abundance, 24-49 % of the total biomass) and cryptophyte Plagioselmis punctata Butch (21-29 % of the total abundance) can be recorded. The analysis of vertical distribution (at so-called deep-water stations) showed that a distribution of phytoplankton numbers at the surface and in the near-bottom layer was practically even (Appendix 2.6.2). The maximum biomass estimates in the near-bottom layer were caused by the presence of large, facultative-plankton forms (different species of genera Navicula, Pinnularia, Campylodiscus, Nitzschia), and also the true-plankton Coscinodiscus and Thalassiosira, which were known to be able to stay in the deep water layers, having massive smooth folds. On average, the abundance in the study region was 75 thousand cell/l, biomass 152,23 mg/m3. Thus, along with the freshwater and freshwater-brackish species, a species composition was formed by marine and brackish-marine species, the maximum estimates of which were recorded at the outlet of the bay. The maximum estimates of quantitative indices were recorded in the southern part of the bay, where the predominant development of diatoms, compared to the northern site, was observed. Among divisions the diatom algae dominated; along with them the cryptophyte algae dominated at the northern site. The even vertical distribution of numbers should be noted in contrast to biomass, which maximum estimates, caused by the occurrence of benhthic and large centric diatoms, were recorded in the near-bottom layer. A diatom alga Cocconeis scutellum and cryptophyte Plagioselmis punctata dominated.

3.7. Zooplankton of the Chaivo Bay

3.7.1. Description of zooplankton by the archive and literary data By the 1999 data of ECS, zooplankton studies have been conducted only at two stations. A total of 11 species of organisms belonging to 3 conditional groups were found from samples. Copepods were the dominants in the species composition; they presented 9 species. In addition to copepods, a cladoceran Podon leuckarti and ostracodes were recorded in samples. At station 8, located near the southern extremity of the Irkimibu Island, zooplankton biomass was 678 mg/m3, abundance 41517 ind./m3. The base of biomass was formed by copepods Sinocalanus tenellus and Acartia clausi1. These copepods and juvenile copepods from the genus Eurytemora made up the greatest abundance of organisms. At station 18, located a little south of the outlet from the bay channel, zooplankton biomass constituted 114 mg/m3, abundance 3425 ind./m3. The base of biomass was formed by copepods Eurytemora americana and juvenile specimens from the genus Eurytemora. Juvenile copepods from the genus Eurytemora prevailed by numbers. The mean abundance of plankton organisms in the Chaivo Bay was 22471 ind./m3, mean biomass 396 mg/m3 by the data of observation at two stations (Ecological studies …, 2001). In 2001, a total of 23 organism forms from 7 groups were recorded in samples. Due to the relatively small depth of the bay, a high number of benthos forms, being untaken for calculations, were observed in samples. Of 23 forms, 16 were related to euplankton, 2 forms were meroplankton, that is, they were the larvae of benthic animals (Polychaeta and Cyrripedia), and 5 plankto-benthic forms (all Harpacticoida and Alona). The majority of species were related to brackish and euryhaline (Sinocalanus tenellus, Tachidius discipes). Freshwater species enduring salinity (Alona quadrangularis) and marine coastal species enduring freshening (Acartia hudsonica , Pseudocalanus newmani, Podon leuckarti)occurred; the latter species penetrate into the very remote parts of the bay.

1 At present this species is redetermined as Acartia hudsonica СахНИРО Отчет по договору Y-00571 72 Zooplankton biomass in the bay varied from 1,77 to 1527,75 mg/m3, averaged 286,14 mg/m3. A group of copepods, being represented by 3 suborders: Calanoida and Cyclopoida (common plankters) and Harpacticoida (plankto-benthos), was the most abundant both in quantitative and qualitative respects. Their mean biomass reached 67,2 %; Acartia hudsonica (31.4 % of the community) was the most abundant. All copepods are the important food organisms and make up the base for feeding the fish-planktophagans of the bay. As the surveys have shown, tidal phenomena change, mainly, the abundance of plankters in the mouth-part of the bay (Latkovskaya et al., 2003).

3.7.2. Characteristic of zooplankton in 2002 Zooplankton was distributed unevenly over the bay area. This is associated with some factors: a level of water mineralization and temperature; river, brook, and tide run-off affect; uneven bottom relief; vegetation development. Three groups (Fig. 3.7.1), described in Chapter 2 (Piltun Bay), formed the bay zooplankton. A total of 8 forms of organisms (Table 3.7.1) were found from samples. All of them were related to copepods. Due to the relatively small depth of the bay, a high number of the near-bottom forms were recorded in samples. The majority of species were related to brackish and euryhaline ones. The abundance of zooplankters in the bay varied within 1615,6 – 65360,0 ind./m3, biomass 36,11–380,90 mg/m3, averaged 187,13 mg/m3. The biomass maximum was specific for the third complex. Nauplii of different copepods prevailed both by abundance and biomass.

Table 3.7.1 A list of organisms occurred in the Chaivo Bay in 2002 № Group Form 1 Sinocalanus tenellus 2 Schmackeria inopina 3 Eurytemora asymmetrica 4 Eurytemora herdmani COPEPODA 5 Acartia hudsonica 6 Oithona similis 7 Harpacticoidae indet. 8 Nauplii copepoda

Table 3.7.2 Zooplankton abundance and biomass in the Chaivo Bay by stations № st. Ch1 Ch2 Ch3 Ch4 Ch5 Ch6 Ch7 Ch8 Ch9 N, 65360,0 31625,0 1768,4 4759,4 1615,6 7000,0 4500,0 6700,0 5100,0 ind./m3 B, mg/m3 380,90 207,00 36,11 161,99 47,68 174,45 148,30 263,85 263,90

СахНИРО Отчет по договору Y-00571 73

Fig. 3.7.1. Distribution of zooplankton complexes in the Chaivo Bay in 2002

СахНИРО Отчет по договору Y-00571 74

3.8. Benthos of the Chaivo Bay

3.8.1. General characteristics of benthos The first attempt of a detail study of the Chaivo Bay bottom biota was done in May- August 1982, when the complex expedition of DVGU (Far East University) collected 42 dredged benthos samples in the region of the Kleye Strait of lagoon, joining the bay with the sea up to the northern extremity of Soniga Island. Sampling was being conducted with the help of a small model of Petersen's grab (0.025 m2) (Volova, Kozmenko, 1984). A species list of benthos consisted of 46 benthic and nekto-benthic organisms, including coelenterates – 6, polychaetes – 11, gastropods – 4, bivalves – 5, mysids – 2, cumaceans – 1, isopods – 2, amphipods – 13, caprellides – 1, decapods – 1 species. The base of species composition was formed by marine euryhaline (79 %) and brackish (21 %) species. Freshwater forms were not found. A few species: Zostera marina, Nucella freicinetti, Littorina kurila, Macoma baltica, Liocyma fluctuosa, and Mytilus trossulus played a significant part in the formation of total biomass. The main biocenoses in the study region were as follows: Mytilus trossulus, Liocyma fluctuosa, Macoma balthica and Zostera marina + Littorina sitkana (Fig. 3.8.1). Biocenosis Mytilus trossulus was observed in the Kleye Strait at 4-5 m depths on coarse о sand with a touch of pebble and shell rock. The water salinity was 22-26 /оо, velocity of current 0,3-0,5 m/sec. The base of biocenosis was formed by marine euryhaline species (94,5 %). The dominating species (M. trossulus) made up more than a half of biomass. N. freicinetti, Chone teres, Aeginina aengimaticus and Nereis pelagica were significant by numbers (Table 3.8.1). Biocenosis Liocyma fluctuosa was located in the central part of the bay from Kleye Strait to the northeastern part of Soniga Island. The biocenosis was found at depths of 2,5-8 m on fine о and coarse sand with gravel under the water salinity of 21-23 /оо. A total of 19 species were recorded in this biocenosis. Its base was formed by marine euryhaline species (89,5 %). A number of brackish species increased, for instance, Eogammarus kygi, Pontoporeia femorata, Kamaka kuthae (Table 3.8.2).

СахНИРО Отчет по договору Y-00571 75

Fig. 3.8.1. Macrozoobenthos communities of the Chaivo Bay (according to Volova, Kozmenko, 1984). Communities: 1 – Mytilus trossulus, 2 – Liocyma fluctuosa, 3 – Macoma balthica, 4 - Littorina sitkana

Table 3.8.1 Composition of the biocenosis Mytilus edulis Species Group N, ind./m2 В, g/m2 M. trossulus Bivalvia 45 194 N. freicinetti Gastropoda 54 42 Sertularia cupressoides Hydrozoa 30 N. pelagica Polychaeta 18 22.8 Corallinomorpharia Rodophyta 22.2 Obelia longissima Hydrozoa 18 M. balthica Bivalvia 21 10.8 L. fluctuosa Bivalvia 6 2.1 Antopleura sp. (?) Ascidiacea 3 1.5 Saduria entomon Isopoda 12 1.02 Pectinaria brevicoma Polychaeta 8 0.6 A. aengimaticus Polychaeta 48 0.6 C. teres Polychaeta 54 0.38 P. granulata Polychaeta 3 0.3 Antopleura orientalis Ascidiacea 3 0.3 Phylodoce sp. Polychaeta 3 0.03 Neomysis orientalis Mysidae 12 0.03 Spinulogammarus spasski Amphipoda 3 0.006 Total 294 366,65

СахНИРО Отчет по договору Y-00571 76 Table 3.8.2 Composition of the biocenosis Liocyma fluctuosa Species Group Ind./m2 G/m2 L. fluctuosa Bivalvia 102 45.6 Abietinaria sp. Hydrozoa 1 M. balthica Bivalvia 3.9 0.95 Glycinde armigera Polychaeta 7 0.48 Cryptonatica aleutica Gastropoda 1.2 0.3 Nephthys caeca Polychaeta 1.2 0.24 L. sitkana Gastropoda 6 0.18 Capitella capitata Polychaeta 5.6 0.1 Ampharete arctica Polychaeta 8.4 0.072 Laternula sp. Bivalvia 6 0.043 Diastylopsis dawsoni Cumacea 6 0.042 Onuphis iridescens Polychaeta 1.2 0.0138 E. kygi Amphipoda 1.2 0.012 S. entomon Isopoda 3.6 0.012 Anisogammarus pugettensis Amphipoda 1.2 0.0084 Ischyrocerus anguipes Amphipoda 1.2 0.007 Echinogammarus viridis2 Amphipoda 1.2 0.005 P. femorata Amphipoda 1.2 0.0024 K. kuthae Amphipoda 1.2 0.0024 Total 164 49,04

Biocenosis Macoma balthica was located by the sides of the above noted one and timed to the undergrowth of Zostera on silty-sand grounds at the depth up to 5 m under the salinity of о 14-23 /оо. The base of this biocenosis was made by marine euryhaline species (75 %) and brackish species (25 %); the dominant species M. balthica is related to the latter ones. In the lagoon conditions, Macoma formed the colonies of 234 ind./m2 in numbers and biomass 83,4 g/m2 (Table 3.8.3).

Table 3.8.3 Composition of the biocenosis Macoma balthica Species Group Ind./m2 G/m2 M. balthica Bivalvia 234 83.4 L. fluctuosa Bivalvia 1.2 1.74 Eogammarus tjuschovi Amphipoda 4.3 0.79 L. sitkana Gastropoda 7.2 0.37 Fluviocingula nipponica Gastropoda 1.8 0.36 Idotea ochotensis Isopoda 1.8 0.24 Sipunculida Sipunculida 1.2 0.104 Bryozoa Bryozoa 0.1 P. femorata Amphipoda 1.2 0.024 S. entomon Isopoda 5.4 0.015 D. dawsini Cumacea 0.6 0.006 I. anguipes Amphipoda 11.4 0.005 Calliopius laeviusculus Amphipoda 2.5 0.0028 Ischyrocerus commensalis Amphipoda 1.2 0.002 Pontoporeia affinis Amphipoda 0.6 0.0012 K. kuthae Amphipoda 1.2 0.0007 Total 275,6 87,1

2 The occurrence of this species in our waters is a point of issue СахНИРО Отчет по договору Y-00571 77 Biocenosis Littorina sitkana was observed at small depths from the eastern side of Soniga Island on silty and silty-sand grounds in the Zostera undergrowth. Salinity in the places of о sampling was 14-22 /оо. This biocenosis was oligomixed; it included only 5 species (Table 3.8.4). The dominant species constituted 95,6 % of the total biomass. о In the conditions of Chaivo Bay, under 14-26 /оо salinity, the formation of oligomixed biocenoses with the domination of marine euryhaline species takes place. These biocenoses are widely distributed in the littoral and sublittoral zones of all the Far East seas. They are timed to the definite types of bottom sediments. Silty grounds are occupied by the biocenoses L. sitkana and M. balthica; M. edulis and L. fluctuosa are located on the coarse-grained grounds.

Table 3.8.4 Composition of the biocenosis Littorina sitkana Species Group Ind./m2 G/m2 L. sitkana Gastropoda 180 30 M. balthica Bivalvia 8 0.85 Sipunkulida Sipunkulida 6 0.32 E. tjuschovi Amphipoda 2 0.015 Idotea ochotensis Isopoda + + Total 196 31.38

The later studies of the Chaivo Bay benthos were conducted by the complex expedition of SakhNIRO and ECS in July 1999 (Ecological studies…, 2001). The processed data of 18 dredged stations, the samples of which were collected with the help of the Petersen’s grab (0.025 m2) or Levanidov’s benthometer (0.16 m2), served the base for the present description. However, due to the incorrect description, given by the authors of this report (for example, two benthos communities, in each of them the sea grass and bivalve Macoma balthica dominated by biomass), we were compeled to make our own description based on the primary materials of processing the benthos samples collected in 1999 (Ecological studies…, 2001). A total of 51 species and forms of benthos organisms were found in the bottom biota composition of Chaivo Bay by the results of a dredged survey (Appendix 3.8.1). Polychaetes (17 species) and amphipods (13 species) formed the base of species composition. Bivalves Macoma baltica (23,4 % of the total biomass), sea grass Zostera asiatica (11,5 %), Z. nana (8,7 %), Z. marina (34,3 %), and green algae Chaetomorpha sp. (11,3 %) were the key species (Table 3.8.5).

Table 3.8.5 Averaged quantitative characteristics of benthos groups from the Chaivo Bay N, Group Species numbers ind./m2 В, g/m2 Biomass, % Algae 2 0.0 83.640 15.7 Magnoliophyta 3 0.0 290.139 54.4 Nemertini 1 1.6 0.016 0.0 Polychaeta 17 279.3 2.687 0.5 Echiuridae 1 0.8 0.035 0.0 Sipuncula 1 0.8 0.002 0.0 Oligochaeta 1 118.5 0.197 0.0 Gastropoda 2 92.0 1.657 0.3 Bivalvia 5 247.7 150.990 28.3 Mysidae 1 6.8 0.099 0.0 Cumacea 1 7.0 0.019 0.0 Amphipoda 13 247.8 1.627 0.3 Isopoda 1 15.0 0.100 0.0

СахНИРО Отчет по договору Y-00571 78 N, Group Species numbers ind./m2 В, g/m2 Biomass, % Decapoda 1 2.3 1.655 0.3 Insecta 1 24.8 0.063 0.0 Total 51 1044.4 532.923 100.0

The mean abundance of organisms over the bay area was 1044 ind./m2. Polychaetes (279 ind./m2; 27 % of the total abundance), amphipods, and bivalves (by 248 ind./m2; 24 %) had the maximum abundance. The mass groups were also gastropods (92 ind./m2; 9 %) and oligochaetes (119 ind./m2; 11 %) (Fig. 3.8.2). The mean biomass of the bay bottom organisms was 530 g/m2. The maximum contribution was made by bivalves (150 g/m2; 28,3 % of the total biomass), sea grass (290 g/m2; 54,4 %), and green algae (84 g/m2; 15,7 %) (Fig. 3.8.3).

1% 2% 2% 9% 27% 11%

24% 24%

Polychaeta Amphipoda Bivalvia Oligochaeta Gastropoda Insecta Isopoda Прочие

Fig. 3.8.2. Ratio of numbers of the main benthos groups from the Chaivo Bay in 1999

2% 16%

54% 28%

Magnoliophyta Biv alv ia Algae Прочие

Fig. 3.8.3. Ratio of biomasses of the main benthos groups from the Chaivo Bay in 1999

A density of the bottom organism colonies in Chaivo Bay was heterogenous (Fig. 3.8.4). The higher estimates of abundance were timed to the place of the channel flowing into the

СахНИРО Отчет по договору Y-00571 79 lagoon and near the southern extremity of Soniga Island at st. №№ 7, 16, and 18 (to 3300 ind./m2). On the rest part of the open area the abundance of bottom organisms did not exceed 1300 ind./m2.

52.65

52.6 10

3000 52.55 89

11 2500 52.5

12 2000 14 13 52.45 7 1500

52.4 6 1615 1000

5 18 52.35 500

17 4 0 52.3 2 1

52.25

143.1 143.15 143.2 143.25 143.3 Fig. 3.8.4. Distribution of benthos numbers (ind./m2) in the Chaivo Bay in 1999 (decimal coordinates)

The biomass distribution of bottom organisms in the Chaivo Bay was heterogenous too (Fig. 3.8.5). The higher estimates were observed in the central part of the bay opposite the place of the channel flowing into the lagoon. There the sites with high biomass were timed, mainly, to the sandy-silt grounds at st. № 18 (2700 g/m2) and formed by the bivalve M. balthica and sea grass Zostera aggregations. The greatest biomass indices were recorded at station 10 (800 g/m2) on the bay periphery, where algae from the genus Cladophora formed its base. On the rest part of the open area the bottom biomass did not exceed 500 g/m2.

СахНИРО Отчет по договору Y-00571 80

52.65

52.6 10

52.55 89 2500

11

52.5 2000

12 14 13 1500 52.45 7

1000 52.4 6 1615

5 18 500 52.35

17 4 0 52.3 2 1

52.25 143.1 143.15 143.2 143.25 143.3 Fig. 3.8.5. Distribution of benthos biomass (g/m2) in the Chaivo Bay in 1999 (decimal coordinates)

3.8.2. Benthos communities When distinguishing the communities based on the clasterization of data by the Shoener’s index, a dendrogram on the similarity of dredged stations in the Chaivo Bay was built (Fig. 3.8.6). The dendrogram shows 3 types of communities, which are well harmonized with a hydrological description of the bay (see above) under the map image (Fig. 3.8.7). Community of sea grass Zostera var occupies the bay area in the region of penetration of the sea tidal waters outside the strong current. A described community was observed at the depth о range of 0,2-2 m on silty-fine sand grounds under the near-bottom water salinity 2,6-29,5 /оо (due to the tidal phase) at stations №№ 1, 2, 5, 6, 7, 8, 11, 13, and 14. Polychaetes (9 species of 32) and amphipods (11 species) made up the base of species composition in the community; the main biomass was formed by sea grass (89,6 %). On the whole, the quantitative indices constituted 1040 ind./m2 and 447 g/m2 (Table 3.8.6).

СахНИРО Отчет по договору Y-00571 81

Fig. 3.8.6. Dendrogram of similarity of the dredged stations in Chaivo Bay in 1999 by the Shoener’s index

Table 3.8.6 Ratio of benthos groups in the community Zostera var. Group Species numbers N, ind./m2 В, g/m2 Biomass, % Sipuncula 1 1.5 0.003 0.0 Polychaeta 9 156.8 0.838 0.2 Oligochaeta 1 143.4 0.268 0.1 Nemertini 1 3.0 0.030 0.0 Mysidae 1 6.9 0.068 0.0 Magnoliophyta 1 0.0 400.880 89.6 Isopoda 1 6.3 0.055 0.0 Insecta 1 34.7 0.087 0.0 Gastropoda 2 163.2 2.873 0.6 Decapoda 1 0.3 0.050 0.0 Cumacea 1 13.2 0.035 0.0 Bivalvia 1 103.7 39.852 8.9 Amphipoda 11 405.7 2.346 0.5 Total 32 1038.9 447.385 100.0

СахНИРО Отчет по договору Y-00571 82

52.65 Условные обозначения:

- сообщество 52.6 Zostera var.;

10 - сообщество Macoma balthica + 52.55 89 Zostera var.;

11 - сообщество Chaetomorpha sp. 52.5

12 14 13 52.45 7

52.4 6 1615

5 18 52.35

17 4 52.3 2 1

52.25

143.1 143.15 143.2 143.25 143.3 Fig. 3.8.7. Main benthos communities of the Chaivo Bay in 1999

Sea grass from the genus Zostera (400 g/m2; 89,6 %) dominated in the community. A significant contribution to the formation of total biomass was made by bivalves M. balthica too (8.9 % of the total biomass). Other species did not play a significant part in the community (1,5 % of the total biomass) (Table 3.8.6). The community with the sea grass Zostera and bivalve Macoma balthica being dominants was observed by the sides from the fairway in places of detritus accumulation. Community Macoma balthica + Zostera var. A described community was observed at depths of 0,7-4,7 m on the grounds from loam to о medium sand under the near-bottom water salinity 19-22 /оо at stations №№ 12, 15, and 18 during sampling. Amphipods and polychaetes (7 and 6 species of 24, respectively) formed the base of species composition; bivalves and sea grass (59 % and 34,1 % of the total biomass, respectively) formed the main biomass of the community. In general, the quantitative indices constituted 1504 ind./m2 and 1123 g/m2 (Table 3.8.7). Bivalves M. balthica (810 ind./m2; 563 g/m2; 50,1 % of the total biomass) and sea grass Zostera var. (383 g/m2; 34,1 %) dominated in the community. A great contribution to the formation of total biomass was also made by bivalves Mytilus trossulus and algae, indefinite to a

СахНИРО Отчет по договору Y-00571 83 species (a total contribution was 13,6 %). Other species did not play a significant part in the community (2,2 % of the total biomass) (Table 3.8.7).

Table 3.8.7 Ratio of benthos groups in the community Macoma balthica + Zostera var. Group Species numbers Ind./m2 G/m2 Biomass, % Polychaeta 6 125.0 0.552 0.0 Oligochaeta 1 222.2 0.244 0.0 Mysidae 1 17.8 0.356 0.0 Magnoliophyta 1 0.0 382.593 34.1 Isopoda 1 40.0 0.267 0.0 Gastropoda 1 22.8 0.593 0.1 Echiuridae 1 4.4 0.200 0.0 Decapoda 1 8.9 7.422 0.7 Bivalvia 3 938.5 662.710 59.0 Amphipoda 7 124.4 1.369 0.1 Algae 1 0.0 66.667 5.9 Total 24 1504.1 1122.971 100.0

A community with the dominant algae Chaetomorpha sp. was observed on the lagoon periphery at sites with the lower salinity. Community Chaetomorpha sp. was observed at depths to 1 m, mainly, on sandy grounds о under the near-bottom water salinity of 0,01-12 /оо at stations №№ 4, 9, and 10 during the survey. (We intentionally excluded station 17 from the list, because, occurring at the inlet into the lagoon, it was a common pattern of marine surf littoral zone, and the domination of algae Chaetomorpha sp. by biomass was, most probably, caused by the error of determination). The community was oligomixed being determined by its location in the brackish zone of the bay. The base of its species composition was formed by amphipods and polychaetes (5 and 4 species of 16, respectively); algae and sea grass made up the main biomass (88,1 % and 11,2 % of the total biomass, respectively). In general, the quantitative indices constituted 121 ind./m2 and 445 g/m2 (Table 3.8.8).

Table 3.8.8 Ratio of benthos groups in the community Chaetomorpha sp.

Group Species numbers N, ind./m2 В, g/m2 Biomass, % Polychaeta 4 26.0 0.192 0.0 Oligochaeta 1 10.7 0.055 0.0 Magnoliophyta 2 0.0 50.000 11.2 Insecta 1 31.9 0.078 0.0 Decapoda 1 3.1 1.807 0.4 Amphipoda 5 49.3 0.681 0.2 Algae 2 0.0 391.667 88.1 Total 16 121.0 444.480 100.0

Algae from the genus Chaetomorpha (325 g/m2; 73,1 % of the total biomass) dominated in the community. A great contribution to the formation of total biomass was also made by algae and sea grass Zostera var., indefinite to a species (a total contribution was 26,2 %). Other species did not play a significant part in the community (0,7 % of the total biomass) (Table 3.8.8).

СахНИРО Отчет по договору Y-00571 84 3.9. Ichthyofauna of the Chaivo Bay

Fish species composition, their abundance and biomass in the Chaivo Bay are undergoing change during a year with the same regularity as in the Piltun Bay. During the expedition works carried out by the Laboratory of Applied Ecology, SakhNIRO in September 2001, a total of 32 fish species from 14 families were found in the Chaivo Bay. By our and literary data, species composition of fish and fish-like species of the Chaivo Bay includes about 44 species (Latkovskaya et al., 2003; Safronov et al., 2003) (Table 3.9.1).

Table 3.9.1 A list of fish and fish-like species of the Chaivo Bay Family Species and subspecies Petromyzontidae Lethenteron japonicum - arctic lamprey **Clupea pallasii – herring Clupeidae ****Sardinops sagax melanosticta – west Pacific sardine *Acipenser medirostris – Sakhalin sturgeon Acipenseridae *Huso dauricus – kaluga sturgeon Oncorhynchus gorbuscha – pink salmon Oncorhynchus keta – chum salmon Oncorhynchus masou – masu salmon Salmonidae Oncorhynchus kisutch – coho salmon ***Salvelinus leucomaenis – Sakhalin char *** Salvelinus malma krascheninnikovi – southern malma *Parahucho perryi – Sakhalin taimen Coregonidae Coregonus ussuriensis – Ussuri whitefish Mallotus villosus – capelin Hypomesus japonicus – smelt Osmeridae H. nipponensis – wakasagi H. olidus – pond smelt Osmerus mordax – Asiatic smelt Carassius auratus gibelio – common wild goldfish Phoxinus perenurus – lake minnow Rodeus sericeus – Amur bitterling Cyprinidae ***Tribolodon brandtii – eastern redfin ***Tribolodon ezoe – Pacific redfin ***Tribolodon hakuensis – big-scaled redfin Cobitidae Cobitis lutheri – loach Misgurnus nikolsky – Nikolsky's loach Balitoridae Barbatula toni – Siberian stone loach Gadidae **Eleginus gracilis – saffron cod Gasterosteus aculeatus – threespine stickleback Pungitius pungitius – ninespine stickleback Gasterosteidae Pungitius sinensis – Amur stickleback Pungitius tymensis – Sakhalin stickleback Opisthocentrus ocellatus – spottyfin gunnel Stihaeidae Pholidapus dybowskii – Dybowsky's blenny Pholididiae Rhodimenichthys dolichogaster – stippled gunnel Zoarcidae Zoarces elongates – Pacific eelpout Hexagrammos octogrammus – masked greenling Hexagrammidae Hexagrammos stelleri – whitespotted greenling СахНИРО Отчет по договору Y-00571 85 Family Species and subspecies Agonidae Pallasina barbata – tubenose poacher Gobiidae Chaenogobius urotaenia Megalocottus platycephalus – flathead sculpin Cottidae Myoxocephalus stelleri – Steller's sculpin Limanda aspera – yellowfin sole ***Platichthys stellatus – starry flounder Pleuronectidae Liopsetta pinnifasciata – banded flounder Pleuronectes quadrituberculatus – Alaska plaice * Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the last years Both inhabitants of marine and brackish waters and anadromous fish are the most widely represented in the Chaivo Bay. Some anadromous fish migrate far for feeding (pink, chum, coho and others), other fish (pond smelts, Sakhalin char, Sakhalin taimen and others) inhabit the bays and not far in the open part of the sea. Dividing into marine and brackish is conditional, to some extent, for fishes, since both occur in a sea and bays. Evidently, some of anadromous fishes (pond smelt, Amur, ninespine, and threespine sticklebacks) feed, mainly, within the bay. Some species enter the bay periodically, are not abundant or fished hardly with gear. For example, Pacific mullet, Sakhalin sturgeon, and kaluga are known from the literary and answering information (Taranets, 1937а, 1937б; Gritzenko, Kostyunin, 1979; Gritzenko, 1990). Ussuri whitefish, being relatively non-abundant, is common in the northeastern bays of the island (Churikov, 1978; Gritzenko, 1990; own observations). By the opinion of some researchers, kaluga and Ussuri whitefish in the bays of northeastern Sakhalin are feeding migrants from the Amur estuary (Churikov, 1978; Gritzenko, 1990). Sakhalin taimen is presented in the bay both by juvenile and adult specimens. Arctic lamprey enters the rivers for spawning in the second half of autumn – early winter (Gritzenko, 1990). Evidently, such species as herring, spottyfin gunnel Opistocentrus ocellatus, Dybowsky's blenny Pholidapus dybowskii, masked greenling Hexagrammos octogrammus, whitespotted greenling Р. stelleri, Alaska plaice, tubenose poacher Pallasina barbata, Steller’s sculpin are more attached to sites with the higher water salinity. They occurred only in the central part of the bay and in the strait joining it with the sea. Sakhalin char, malma, pond and Asiatic smelts, saffron cod, threespine, ninespine and Amur sticklebacks, Pacific redfins, Pacific eelpout, flathead sculpin, starry and banded flounders can be related to the euryhaline species being observed on the major part of the bay area. Many of them (Sakhalin char, pond and Asiatic smelts, flathead sculpin, starry flounder and others) were observed both in the bay and in the sea. As a rule, species more inhabiting brackish waters, were not found far from the mouth of straits in the open part of the sea. For example, pond smelt Hypomesus olidus occurred in trawl catches close to the bays only at depths of about 20 m (Bukin et al., 1999). Freshwater fishes were found at sites of the bay with the very low water salinity. Lake minnow and Siberian stone loach Barbatula toni occurred in the bay bight in its northwestern part. It is interesting that no large rivers flow in the place of their occurrence. Perhaps, common wild goldfish inhabits the freshened sites in the southern part of the bay; earlier it was observed in the channel joining the bays Nyisky and Chaivo (Latkovskaya et al., 2001). In September 2001, by the results of our surveys (Latkovskaya et al., 2003), pond smelts, flathead sculpin, starry flounder, and threespine stickleback were the most frequent in the bay. Some species (malma, ninespine stickleback, whitespotted greenling, Steller’s sculpin, Alaska plaice) were found only at one of ichthyological stations (Table 3.9.2).

СахНИРО Отчет по договору Y-00571 86 Table 3.9.2 Fish frequency, abundance and biomass in the Chaivo Bay in September 2001 from the beach seine catches Mean Mean biomass, Relative biomass, Species Frequency, % abundance, g/m2 % ind./m2 Clupea pallasii 20,0 0,008 0,036 0,052 Salvelinus leucomaenis 50,0 0,014 2,814 4,086 S. malma krascheninnikovi 10,0 0,000 0,010 0,014 Hypomesus spp. 80,0 1,200 10,858 15,765 Osmerus mordax dentex 20,0 0,017 0,110 0,160 Tribolodon hakuensis 40,0 0,176 8,365 12,146 Tribolodon spp. (juveniles) 40,0 2,268 22,651 32,887 Eleginus gracilis 40,0 0,186 8,208 11,917 Gasterosteus aculeatus 70,0 0,021 0,054 0,078 Pungitius pungitius 10,0 0,018 0,025 0,037 Pungitius sinensis 50,0 0,283 0,543 0,788 Zoarces elongatus 40,0 0,074 3,106 4,510 Opisthocentrus ocellatus 20,0 0,028 0,370 0,537 Hexagrammos octogrammus 20,0 0,004 0,221 0,321 Hexagrammos stelleri 10,0 0,005 0,129 0,188 Megalocottus platycephalus 80,0 0,027 3,894 5,654 Myoxocephalus stelleri 10,0 0,001 0,368 0,535 Platichthys stellatus 80,0 0,228 5,450 7,913 Liopsetta pinnifasciata 50,0 0,060 1,636 2,376 Pleuronectes quadrituberculatus 10,0 0,001 0,023 0,033 Pallasina barbata 20,0 0,001 0,002 0,002

Mean estimates of fish abundance per m2 and their biomass per m2 varied widely: abundance from 0,001 to 2,268 ind./m2, biomass from 0,002 to 31,016 g/m2. A high frequency of pond smelts and starry flounder determines the relatively high estimates of their mean numbers (1,200 and 0,228 ind./m2) and biomasses (10,858 and 5,450 g/m2). At the same time, this dependence is not always expressed. For example, some species (Pacific redfins, saffron cod) have high mean biomasses on the relatively limited bay area (31,016 and 8,208, respectively) (Table 3.9.2). The bay fishery is based on different objects due to a season: Pacific herring in late spring – early summer, Pacific salmon in summer and autumn (during their run for spawning), saffron cod in winter. Pacific redfins, smelts, Sakhalin char, sculpins, flounders are captured as a “bycatch”. Chaivo Bay is of great importance for Sakhalin aboriginal people living on the island shores. Their economy is based on fishery in many respects. Five patrimonial communities: “Minmif”, “Koivongun”, “Ungir”, “Chaivo”, and “Nyivo” are located on the bay shore. In total, 22 persons live in these settlements (information was obtained in the Department of National Policy of Administration of Sakhalin Region). During the anadromous migration of Pacific salmon to the river mouths, the communities receive special quota for fishing in the bay. In addition, nivkhs conduct the fishing of other fish species in different year seasons.

3.9.1. Main commercial species Among Pacific salmon, pink, chum, masu, and coho salmon enter the rivers flowing into the Chaivo Bay for spawning. Pink and chum salmon have a commercial importance. Spawning grounds of a “pink salmon” type prevailed by size. However, in some rivers

СахНИРО Отчет по договору Y-00571 87 (Bolshoy Paromay, Val, Askasay and others) there are chum and coho spawning grounds too. A total area of salmon spawning grounds in rivers flowing into the Chaivo Bay is 578300 m2 (Table 3.9.3) (Report…, 1957).

Table 3.9.3 Rivers of the Chaivo Bay basin and their spawning areas Length, Spawning area, Species of Pacific River Water area, km2 km m2 salmon Ossoy 41 183 5400 pink Nutovo 35 102 16000 pink Maliy Garomay 40 119 24000 pink Bolshoy Garomay 42 204 33600 pink, chum, coho Khanduza 12 26,3 600 pink Val 112 1440 313500 pink, chum, coho Askasay 95 535 100700 pink, chum, coho Evay 117 578 84500 pink, chum, coho

Biology of Pacific salmon in the Chaivo Bay does not differ significantly from the other regions of northeastern Sakhalin.

Pink salmon. Under the mean density (140 ind./100 m2) of filling the spawning grounds with pink spawners, 809,6 thousand fish run through the Chaivo Bay during the period of their anadromous migration. At the mean long-term weight of one individual of 1,22 kg, the annual pink biomass constitutes 987,7 t, on average. In odd years about 11,9 million pink fry run through the bay for the sea feeding. In even years – 60,3 million fry.

Chum salmon. By the data of episodical observations (1994), specimens at 3+ and 4+ age prevail greatly by abundance. The elder age groups are practically absent (Kovtun, 1995). In September 2001, chum salmon, migrating from a sea, were observed in the strait in small numbers. Fish lengths varied from 68 to 79 cm, weights from 2975 to 5000 g. Their age was 4+ - 5+. Gonads of specimens were at IV stage of maturity, absolute individual fecundity of females was 2551 – 3657 eggs.

Coho salmon. By the data of episodical observations (1994), specimens at 32+ age prevail greatly by abundance among mature fish (Kovtun, 1995). In September 2001, this species was found in the strait during its anadromous migration. Fish lengths varied from 65,0 to 75,0 cm, weights from 3057 to 49322 g. Fish were at 21+ - 22+ age (Kovtun, 1989). Juveniles stayed in fresh waters at 1+ (36,4%) - 2+ (63,6%) age. Data on the chum salmon age from our samples do not differ from the data of other researches (Gritzenko, 1973; Zhulkov, 1978; Gritzenko, 1990). Only males occurred in samples.

Masu salmon. This species is not abundant. Fry are common in rivers flowing into the bay.

Pacific salmon are captured irregularly by the fishing companies due to the fish abundance. National patrimonial communities conduct fishing practically every year. The fishing sites attached to the companies in Chaivo Bay are given in Table 3.9.4 (A list of commercial sites…, 1998).

СахНИРО Отчет по договору Y-00571 88 Table 3.9.4 Commercial sites used by companies in the Chaivo Bay № of Borders Extension, km User site Evay River – 2 km south of Khanduza 1 River – northern extremity of the 11 NSKH «Ungyr» Arakovsky spit Patrimonial 2 km south of Khanduza River – 2 km 2 4 community north of Khanduza River “Kevongun” Northern extremity of Arakovsky spit – Fish collective farm 3 southern extremity of Soniga Island – 5 «Vostok» Chaivo spit Southern extrenity of Soniga Island – ООО «Fishing 4 8 northern extrenity of Soniga Island company Nogliki» Northern extrenity of Soniga Island – 5 9 MGP «Val» southern extremity of Irkimbu Island

Saffron cod In September 2001, saffron cod of 6,8 to 32,7 cm long and of 2,3 to 30,4 cm weigh at the age of 0+ to 4+ occurred in the bay (Latkovskaya et al., 2003). The dominants were fish 15-19 cm long (Fig. 3.9.1) and 30-50 g weigh (Fig. 3.9.2), at 1+ - 2+ age (Fig. 3.9.3). In the period of observations, mainly, immature and first maturing specimens inhabited the bay. Females dominated by abundance (64,0 %). In autumn, mature fish occurred, mainly, in the open part of the sea in northeastern Sakhalin (Bukin et al., 1999; Smirnov et al., 2000). Indices of fullness for saffron cod stomachs varied from 0 to 4; 15,3 % of specimens had empty stomachs.

25,0

20,0

15,0 % 10,0

5,0

0,0 7 8 9 101112131415161718192021222324252627282930313233 Длина, см

Fig. 3.9.1. Distribution of saffron cod by the length AC in the Chaivo Bay in September 2001 (n = 268)

СахНИРО Отчет по договору Y-00571 89

35,0

30,0

25,0

20,0 % 15,0

10,0

5,0

0,0 10 30 50 70 90 110 130 150 170 190 210 230 250 270 290 310 Масса, г

Fig. 3.9.2. Distribution of saffron cod by the body weight in the Chaivo Bay in September 2001 (n = 268)

80,0

70,0 60,0 50,0

% 40,0

30,0 20,0

10,0 0,0 0+ 1+ 2+ 3+ 4+ Возраст, годы

Fig. 3.9.3. Age composition of saffron cod in the Chaivo Bay in September 2001 (n = 122)

The mean length of saffron cod caught from the bay varied by years from 21,8 to 28,9 cm (Fig. 3.9.4).

31 29 см

, 27 АС 25 23 длина 21 19

Средняя 17 15 1988 1990 1992 1994 1996 1998 2000 2002 Годы наблюдений

Fig. 3.9.4. Dynamics of the mean length of saffron cod (cm) in the Chaivo Bay, 1988-2002 (except for 1991 and 1995)

СахНИРО Отчет по договору Y-00571 90

By the beginning of February, majority of fish (60,0-70 %), as a rule, are in the pre- spawning and spawning states. The completely spawned fish constituted from 5,0 to 20,0 %. Usually, a number of the annually settled gear in the Chaivo Bay does not exceed 60-70 units. By the official data (given to the management office of “Sakhalinrybvod”), a percentage of saffron cod in this bay varied from 0 to 23,2% of the total catch. Compositions of catches in January 1991 and 1992 have been identified during scientific-research works. In that period, saffron cod constituted to 28 % of the total catch (Fig. 3.9.5). A catch of saffron cod in the bay varied from 4 t (1992) to 82 t (1987), averaged 27,2 t. Numbers of gear used for fishery changed from 29 to 53 units.

Прочие

Сельдь

Корюшка

Бельдюга

Пол. камбала

Пл.бычок

Навага

0 1020304050 % состав в уловах

Fig. 3.9.5. A species composition of catches by biomass (in %) in the Chaivo Bay in January 1991-1992

Flathead sculpin In September 2001, specimens of 5,7 to 53,0 cm long and of 2,2 to 1496 g weigh at the age of 1+ - 11+ occurred in the bay (Latkovskaya et al., 2003). The dominants were fish 15,0 – 17,0 cm long at 2+ - 5+ age (Fig. 3.9.6, 3.9.7). Specimens longer than 41,0 cm were represented only by females. Flathead sculpin begins to mature in mass at 3+ age. Females dominated by abundance (62,7 %). Specimens with gonads at II, II-III, III stages of maturity were found. The maturing and mature fish prevailed (67,1 %). Indices of fullness for flathead sculpin stomachs varied from 0 to 3, averaged 1,1. 48,0 % of specimens had empty stomachs form catches by the beach seine. Pond smelts, Pacific eelpout, starry flounder, and molluscs, shrimps, small crabs (of invertebrates) were found in its food bolus. Biological indices of flathead sculpin in the Chaivo Bay do not differ from the earlier data (Volodin, 1999). A catch of flathead sculpin varied from 80 t (2000) to 315 t (1988), averaged 218,5 t.

СахНИРО Отчет по договору Y-00571 91

14,0

12,0

10,0

8,0 % 6,0

4,0

2,0

0,0 6 1014182226303438424650 Длина, см

Fig. 3.9.6. Distribution of flathead sculpin by the length AD in the Chaivo Bay in September 2001 (n = 133)

45,0 40,0 35,0 30,0 25,0 % 20,0 15,0 10,0 5,0 0,0 1+ 3+ 5+ 7+ 9+ 11+ Возраст, год ы

Fig. 3.9.7. Age composition of flathead sculpin in the Chaivo Bay in September 2001 (n = 87)

A situation, when during sorting the multiple-species catch only saffron cod and smelts are taken (smelts are used only by fishermen), and flounders and Pacific eelpout are not counted at all, being named together with flathead sculpin as “sculpin” in the statistic reports, is common for the Chaivo Bay as for the Piltun Bay. A percentage composition of catches is given in Fig. 3.9.8.

СахНИРО Отчет по договору Y-00571 92

Пол.камбала

Зубастая корюшка

Бельдюга

Пл.бычок

Навага

0 1020304050607080 %

1991 2000

Fig. 3.9.8. A species composition of «sculpin» from catches in the Chaivo Bay (in %, by biomass) by the data of 1991 and 2000

3.9.2. Secondary commercial and perspective for fishery species

Pacific herring During the summer, Pacific herring feed in the open part of the sea and bay, and spend winter in the lagoon (Gritzenko, 1990). In the Chaivo Bay, only juvenile herring were observed during the study period. Fish lengths varied from 6,6 to 13,8 cm, weight from 2,3 to 21,6 g. The occurrence of juvenile herring in the channel proves the fact that they periodically move out of the bay to the sea. Data on distribution of the herring size composition from catches in the Chaivo Bay are given in Fig. 3.9.9 and 3.9.10. Since 1995, herring fishery in the Chaivo Bay practically has been absent due to the disinterest of the fishery organizations.

45,0 40,0 35,0 30,0 25,0 % 20,0 15,0 10,0 5,0 0,0 7 8 9 1011121314 Длина, см

Fig. 3.9.9. Distribution of Pacific herring by the length AC in the Chaivo Bay in September 2001 (n = 26)

СахНИРО Отчет по договору Y-00571 93

70,0

60,0

50,0

40,0 % 30,0

20,0

10,0

0,0 468102030 Масса, г

Fig. 3.9.10. Distribution of Pacific herring by the body weight in the Chaivo Bay in September 2001 (n = 26)

Sakhalin char During the feeding period, Sakhalin char do not migrate far to the sea and inhabit, mainly, the freshened sites (Gritzenko, 1969; Gritzenko, 1990). By our data (Latkovskaya et al., 2003), in September 2001, fish of 16,3 to 65,5 cm long (Fig. 3.9.11) and of 53 to 2771 g weigh, at the age from 3+ to 9+ (Fig. 3.9.12) occurred in the Chaivo Bay. Specimens 16-24 cm long at 4+ - 5+ age prevailed. Both the present-year migrants and mature fish occurred in samples. Females dominated insignificantly by numbers (53,8 %). Specimens were at II, III, III-IV, IV, VI-II stages of maturity. Sakhalin char spawned in rivers during the study period. This was proved by the occurrence of fish with gonads at VI-II stages of maturity. Our data do not differ from the known ones. The main spawning of Sakhalin char in Sakhalin rivers takes place in September (Gritzenko, 1969; Gritzenko, 1990, 2002). Our data on the date of Sakhalin char spawning in Sakhalin rivers do not differ from the known ones (Gritzenko, 1969; Gritzenko, 1990, 2002).

25,0

20,0

15,0 % 10,0

5,0

0,0 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 Самцы, n = 28 Длина, см Самки, n = 29

Fig. 3.9.11. Distribution of Sakhalin char by the length AC in the Chaivo Bay in September 2001 (n = 57)

СахНИРО Отчет по договору Y-00571 94

35,0

30,0

25,0

20,0 % 15,0

10,0

5,0

0,0 3+ 4+ 5+ 6+ 7+ 8+ 9+ Возраст, годы

Fig. 3.9.12. Age composition of Sakhalin char in the Chaivo Bay in September 2001 (n = 54)

A fullness of stomachs for Sakhalin char was not high (1,8, on average). 23,2 % of specimens had empty stomachs. A content of stomachs was analyzed for 24 fish 17,0-65,0 cm long (Table 3.9.5). In the Chaivo Bay, Sakhalin char behaves like an ichthyophagan. Food objects from large Sakhalin char reached 18 cm in length (Asiatic smelt O. mordax dentex). Juveniles of three species of sticklebacks play an important part in its diet in the bay. Small crustaceans made up a significant part in stomachs of fish 17,0 – 25,6 cm long. This species is an object for the amateur fishery.

Table 3.9.5 A content composition of alimentaly canals of Sakhalin char from the Chaivo Bay in September 2001 (n = 24) Proportion of the total Food object Frequency, % n food objects, % Osmerus mordax dentex 12,50 33,45 3 Hypomesus spp. 4,17 1,27 1 Osmeridae indet. (semi-digested) 45,83 26,86 11 Osmeridae (total) 54,2 61,58 13 Gasterosteus aculeatus 8,33 4,69 2 Pungitius sp. 16,67 9,12 4 Gasterosteidae (total) 25,00 13,80 6 Clupea pallasi 4,17 12,71 1 Pisces (semi-digested) 16,67 5,94 4 Pisces (total) 91,67 94,11 22 Shrimps 16,67 5,62 4 Small crustaceans 16,67 0,35 4

Southern malma (Salvelinus malma krasheninnikovi) In September 2001, this species was of 23,0 to 41,0 cm long and of 24,8 to 750,0 g weigh, at the age of 3+ to 5+ from our catches (Latkovskaya et al., 2003). Juveniles stayed in fresh waters at the age of 3+ to 4+. Specimens had gonads at II-III, III, III-IV, IV stages of maturity. Fish at III and IV stages prevailed by numbers. All the examined fish had empty stomachs. This species does not feed in the northeastern Sakhalin bays (Gritzenko, 1990).

СахНИРО Отчет по договору Y-00571 95 Evidently, the fish, migrating to rivers for spawning were found in the Chaivo Bay. This species is an object for the amateur fishery.

Pond smelts In September 2001, three species of pond smelts: H. nipponensis, H. olidus, H. japonicus occurred in catches. Fish lengths varied from 2,5 to 18,0 cm, weight from 0,14 to 43,4 g (Latkovskaya et al., 2003). Their age varied from 0+ to 4+. Specimens of 9,0 to 12,0 cm long at 2+ age prevailed by numbers. Juveniles of 2,5 to 6,0 cm long and of 0,14 to 0,83 g were found in the northern part of the bay. A fullness of stomachs for pond smelts varied from 0 to 4. 28,6 % of fish had empty stomachs. Larval insects and mysids formed the base of the diet for pond smelts in the bay during the study period.

Asiatic smelt (Osmerus mordax dentex) During the study (Latkovskaya et al., 2003), Juvenile Asiatic smelts of 4,4 to 14,8 cm long (Fig. 3.9.13) were found in the Chaivo Bay. Smelt fry (4,4 cm long and 0,38 g weigh) was found in the sea strait. Along the northeastern Sakhalin shore, Asiatic smelt is common in the open part of the sea (Bukin et al., 1999; Smirnov et al., 2000). For instance, all age groups of the Asiatic smelt occur in the Nyisky Bay round the year (Gritzenko et al., 1984; Gritzenko, 1990, 2002). This species is captured in small numbers in winter during the saffron cod fishing as a bycatch.

50,0 45,0 40,0 35,0 30,0

% 25,0 20,0 15,0 10,0 5,0 0,0 5 7 9 111315171921232527293133 Длина, см

Fig. 3.9.13. Distribution of Asiatic smelt by the length AC in the Chaivo Bay in September 2001 (n = 198)

Eastern redfin (Tribolodon brandi) In September 2001, fish of 7,0 to 45,0 cm long were found in the Chaivo Bay (Latkovskaya et al., 2003). Specimens 35 - 38 cm long and 450 - 650 g weigh, at 4+ - 6+ age dominated by numbers among the mature fish (Fig. 3.9.14, 3.9.15, 3.9.16). Females prevailed by numbers among fish longer than 39,0 cm (Fig. 3.9.14). A small sample (25 ind.) made it impossible to conclude on the sex ratio. Males prevailed by numbers in the examined sample. Specimens at II and III stages of maturity dominated. Fish with gonads at IV stage of maturity occurred sporadically. By September, eastern redfins have already completed their spawning. Molluscs (24,0 % of the analyzed stomachs) and detritus (16,0 %) prevailed in fish stomachs by frequency. This species is an object for the amateur fishery.

СахНИРО Отчет по договору Y-00571 96

35,0

30,0

25,0

20,0 % 15,0

10,0

5,0

0,0 33 34 35 36 37 38 39 40 41 42 43 44 45

Самцы, n = 16 Длина, см Самки, n = 9

Fig. 3.9.14. Distribution of mature eastern redfin by the length AC in the Chaivo Bay in September 2001

30,0

25,0

20,0

% 15,0

10,0

5,0

0,0 450 500 550 600 650 700 750 800 850 900 950 1000 1050 Масса, г

Fig. 3.9.15. Distribution of mature eastern redfin by the body weight in the Chaivo Bay in September 2001 (n = 25)

50,0 45,0 40,0 35,0 30,0

% 25,0 20,0 15,0 10,0 5,0 0,0 4+ 5+ 6+ 7+ 8+ Возраст, годы

Fig. 3.9.16. Age composition of mature eastern redfin in the Chaivo Bay in September 2001 (n = 25)

СахНИРО Отчет по договору Y-00571 97 Big-scaled redfin (T. hakuensis) In September 2001, fish of 8,2 to 35,0 cm long and of 6,6 to 556,0 g weigh occurred in catches (Latkovskaya et al., 2003). Specimens 10 - 14 cm long and about 50 g weigh prevailed by numbers (Fig. 3.9.17, 3.9.18). The rest size groups were distributed relatively even. Fish to 19,0 cm and longer than 33,0 cm were represented only by females. Males significantly prevailed by numbers among specimens of 20,0 to 26,0 cm. Specimens at 4+ - 6+ age dominated by numbers among mature fish (Fig. 3.9.19). Females significantly prevailed by numbers (69,7 %) over the males. Big-scaled redfin were still spawning. Males always prevailed by numbers on spawning grounds (Gritzenko, 1990). Fish with gonads at II, III, IV, VI-II stages of maturity were found. The pre-spawning specimens at IV stage of maturity constituted 13,6 % in the bay. A fullness of fish stomachs varied from 0 to 4, averaged 1,3. 30,9 % of fish had empty stomachs. This species is an object for the amateur fishery.

16,0

14,0

12,0

10,0

% 8,0

6,0

4,0

2,0

0,0 9 1011121314151617181920212223242526272829303132333435 Длина, см

Fig. 3.9.17. Distribution of big-scaled redfin by the length AC in the Chaivo Bay in September 2001 (n = 113)

60,0

50,0

40,0

% 30,0

20,0

10,0

0,0 50 100 150 200 250 300 350 400 450 500 550 600 Масса, г

Fig. 3.9.18. Distribution of big-scaled redfin by the body weight in the Chaivo Bay in September 2001 (n = 113)

СахНИРО Отчет по договору Y-00571 98

30,0

25,0

20,0

% 15,0

10,0

5,0

0,0 3+ 4+ 5+ 6+ Возраст, годы

Fig. 3.9.19. Age composition of mature big-scaled redfin in the Chaivo Bay in September 2001 (n = 58)

Pacific eelpout In September, Pacific eelpout of 9,5 to 39,0 cm long occurred in catches (Latkovskaya et al., 2003). Specimens of 10 to 12 cm prevailed by numbers (Fig. 3.9.20). The rest size groups to 30 cm in length were distributed relatively even. Females to 21 cm long prevailed by numbers. Males dominated at the fish length more than 26 cm. The mean length of males (23,9 ± 1,03 cm) was more than of females (20,7 ± 1,11 cm). Mature specimens were at III stage of maturity. Fish with gonads at II and IV stages occurred in small numbers. A fullness of the eelpout stomachs was from 0 to 3. Pacific eelpout is captured in winter in small numbers as a bycatch during the saffron cod fishing.

25,0

20,0

15,0 % 10,0

5,0

0,0 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 Длина, см

Fig. 3.9.20. Distribution of Pacific eelpout by the length AB in the Chaivo Bay in September 2001 (n = 166)

Steller’s sculpin (Myoxocephalus stelleri) This species inhabit the open part of the sea at the relatively small depths. Fish of 22,6 to 58,0 cm long and of 220 to 2510 g weigh, at 3+ - 12+ age were found in the sea strait of the Chaivo Bay in September 2001 (Latkovskaya et al., 2003). The examined specimens had gonads, mainly, at III stage of maturity. This species occurs in winter catches in small numbers as a bycatch during the saffron cod fishing. Starry flounder

СахНИРО Отчет по договору Y-00571 99 In September 2001, fish of 2,4 to 33,5 cm long and of 0,14 to 470 g weigh, at the age of 0+ to 9+ occurred in the Chaivo Bay (Latkovskaya et al., 2003). Specimens with body lengths of 12,0–16,0 cm and at 1+ - 3+ age prevailed by numbers (Fig. 3.9.21, 3.9.22). Length and weight of different age groups of the flounder are given in Table 3.9.6. A ratio between females and males (138 ind.) was 2,9 : 1. It should be noted that a sex was determined not for all the examined specimens. Female domination by numbers in the bay is undoubted, although the given index may be a little lesser. Fingerlings were caught in the more freshened parts of the bay (southwestern and northwestern parts). In September their lengths varied from 2,4 to 6,5 cm, weights from 0,2 to 4,8 g. The occurrence of fingerlings in the bay proves the fact that after settling the larvae on the bottom, a part of juveniles migrate to the freshened zones of the sea. By our observations, they are common in Sakhalin rivers (Poronai, Naiba, Manuy and others) at a distance of several kilometers from their mouths. Fish from the elder age groups (5+ - 8+) were found only in the sea strait. During the study period, mainly, immature and maturing specimens with gonads at II stage of maturity fed in the bay.

25,0

20,0

15,0 % 10,0

5,0

0,0 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 Длина, см

Fig. 3.9.21. Distribution of starry flounder by the length AC in the Chaivo Bay in September 2001 (n = 443)

60,0 50,0 40,0

% 30,0 20,0 10,0 0,0 0+ 1+ 2+ 3+ 4+ 9+ 6+ 8+ 5+ Возраст, годы

Fig. 3.9.22. Age composition of starry flounder in the Chaivo Bay in September 2001 (n = 126)

Starry flounder fed relatively intensive in the bay. Only 5,0 % of fish had empty stomachs. A fullness of the flounder stomachs were 1-4, averaged 2,1. This species is an object of the amateur fishery.

СахНИРО Отчет по договору Y-00571 100

Table 3.9.6 Length and weight of starry flounder from the different age groups in the Chaivo Bay in September 2001 (n = 182) Length, cm Weight, g Age Sex n Lim M ± m σ Lim M ± m σ 0+ Juv 2,8 - 4,4 3,6 ± 0,19 0,61 0,2 - 1,0 0,4 ± 0,09 0,27 10 1+ Juv 8,2 - 13,0 9,5 ± 0,45 1,49 6,3 - 27,2 11,9 ± 2,16 7,17 11 Male 11,2 - 15,2 13,0 ± 0,26 1,03 16,3 - 43,0 26,6 ± 1,73 6,71 15 2+ Juv 7,5 - 14,3 11,8 ± 0,34 1,75 5,4 - 35,3 20,8 ± 1,72 8,77 26 Female 9,4 - 14,4 12,5 ± 0,19 1,30 9,7 - 38,5 24 ± 1,05 7,19 47 Juv 12,4 - 16,0 13,9 ± 0,31 1,02 20,5 - 53,2 33,4 ± 2,91 9,64 11 3+ Male 12,7 - 17,2 14,7 ± 0,82 1,83 23,7 - 69,2 40,4 ± 8,06 18,01 5 Female 12,4 - 18,2 14,8 ± 0,37 1,82 21,7 - 77,5 41,5 ± 3,59 17,58 24 Male 13,8 - 19,2 16,8 ± 0,69 1,82 30,8 - 77,5 55,9 ± 5,99 15,85 7 4+ Female 13,2 - 19,0 16,8 ± 0,40 1,64 27,8 - 77,7 56,8 ± 3,49 14,37 17 5+ Male 18,0 18,0 0,00 67,6 67,6 0,00 1 Female 17,0 - 24,5 19,9 ± 1,64 3,29 60,0 - 185,0 104,7 ± 27,99 55,99 4 6+ Male 23,6 23,6 0,00 172,5 172,5 0,00 1 Male 29,0 29,0 0,00 247,0 247,0 0,00 1 8+ Female 28,0 28,0 0,00 262,0 262,0 0,00 1 9+ Male 33,5 33,5 0,00 521,0 521,0 0,00 1

Banded flounder Both mature fish and juveniles (including fingerlings) are distributed practically all over the Chaivo Bay, including the heavily freshened sites. The fish occurrence in the strait proves the fact that some part of flounders periodically move out of the bay into the open part of the sea. In September 2001, specimens of 4,2 to 39,0 cm long and of 0,8 to 530 g weigh, at the age of 0+ to 12+ occurred in catches during the study period (Latkovskaya et al., 2003). Fish 16- 27 cm long at 4+ - 9+ age prevailed by numbers (Fig. 3.9.23, 3.9.24). There were no specimens at 1+ and 2+ age (Fig. 3.9.24). Evidently, their habitat areas could be absent in a scheme of fishing. Large fish (more than 27,0 cm) were represented only by females.

25,0

20,0

15,0 % 10,0

5,0

0,0 15 17 19 21 23 25 27 29 31 33 35 37 39

Самцы, n = 45 Длина, см Самки, n = 46

Fig. 3.9.23. Distribution of males and females of the banded flounder by the length AC in the Chaivo Bay in September 2001

СахНИРО Отчет по договору Y-00571 101

25,0

20,0

15,0 % 10,0

5,0

0,0 0+ 2+ 4+ 6+ 8+ 10+ 12+ Возраст, год ы

Fig. 3.9.24. Age composition of banded flounder in the Chaivo Bay in September 2001 (n = 92)

Sizes of different age groups of the banded flounder are given in Table 3.9.7. A ratio between males and females was close to 1:1; females prevailed a little by numbers (52,2 %). The beginning of gonad maturation (III stage of maturity) was noted for flounders under the length of 14,0-17,0 cm at the age of 3+ - 4+ ; for males under the lesser sizes of body. Fish of more than 18,0 cm long and at 4+ - 5+ age become mature in mass. A complete maturation of gonads for fish from the mature part of the population occurs in the period of spawning, evidently, under a somewhat greater length for fish from the younger age groups. A fullness of flounder stomachs from the beach seine catches varied from 0 to 4, averaged 2,26. 8,0 % of fish had empty stomachs. Bivalves constituted a significant part in stomachs of the examined specimens. Banded flounder is captured in the bay in winter period as a bycatch during the saffron cod fishing.

Table 3.9.7 Length and weight of banded flounder from the different age groups in the Chaivo Bay in September 2001 (n = 91) Length, cm Weight, g Age Sex n Lim M ± m σ Lim M ± m σ 0+ juv 3,4 - 6,5 5,8 ± 0,49 1,19 0,4 - 3,34 2,2 ± 0,43 1,04 6 Male 14,2 - 15,8 15,1 ± 0,16 0,51 39,0 - 49,4 43,2 ± 1,13 3,56 10 3+ Female 15,0 - 16,6 15,6 ± 0,5 0,87 42,3 - 50,6 45,1 ± 2,73 4,74 3 Male 14,3 - 20,4 17 ± 0,47 1,68 36,8 - 98,0 60,9 ± 5,08 18,33 13 4+ Female 15,3 - 23,3 17,4 ± 1,02 2,71 46,4 - 143,0 65 ± 13,15 34,79 7 Male 17,5 - 21,5 19,3 ± 0,44 1,40 66,2 - 121,0 90,7 ± 5,90 18,64 10 5+ Female 16,6 - 25,5 21,1 ± 1,99 3,98 53,7 - 217,5 141,8 ± 42,84 85,67 4 Male 18,8 - 25,8 21 ± 1,62 3,23 74,4 - 205,0 114,6 ± 30,35 60,69 4 6+ Female 23,8 - 27,6 25,8 ± 0,34 1,06 161,0 - 260,0 215,4 ± 10,61 33,57 10 Male 25,0 25,0 0,00 183,0 183,0 0,00 1 7+ Female 23,8 - 39,0 27,7 ± 1,5 4,51 179,0 - 320,0 246,2 ± 17,24 51,73 9 Male 25 - 26,8 26,1 ± 0,39 0,77 187,0 - 251,0 213,9 ± 15,13 30,27 4 8+ Female 19,8 - 30 25,1 ± 2,95 5,11 237,0 - 447,0 309,0 ± 69,02 119,55 3 9+ Female 31,0 31,0 0,00 415,0 - 420,0 417,5 ± 2,5,0 3,54 2 10+ Female 23,0 - 32,0 27,5 ± 4,5 6,36 484,0 - 528,0 506,0 ± 22,00 31,11 2 11+ Female 31,0 - 33,6 32,5 ± 0,79 1,36 396,0 - 515,6 457,2 ± 34,55 59,85 3 12+ female 35,0 35,0 0,00 656,0 656,0 0,00 1

СахНИРО Отчет по договору Y-00571 102 3.9.3. Mass non-commercial species

Threespine stickleback In September 2001, fish of 6,9 to 9,7 cm long and of 0,1 to 6,4 g weigh occurred in the sea strait of the Chaivo Bay (Latkovskaya et al., 2003). All specimens were immature with gonads at II and III stages of maturity. Females prevailed by numbers. Perhaps, this is connected with the fact that males mature under the lesser sizes. Evidently, mature specimens occurred in rivers. Mature specimens at II-VI stages of maturity were found sporadically at the freshened sites of the bay. By our observations, a mass spawning of threespine stickleback in the island water bodies takes place, as a rule, in July-August. So, a significant part of fish could still occur in the water courses flowing into the Chaivo Bay during the study period. A fullness of fish stomachs varied from 0 to 4. 17,6% had empty stomachs. Insects and their larvae, and fish eggs were found in the stickleback’s stomachs.

Ninespine stickleback (Pungitius pungitius) This species was found only in the sea strait of the Chaivo Bay. Fish lengths varied from 3,8 to 7,2 cm, weights from 0,3 to 2,3 g (Latkovskaya et al., 2003). Practically all specimens were after the spawning with gonads at VI-II stages of maturity. This proves that during the study period fish completed their part in the spawning process occur in the bay. Females dominated significantly by numbers. Perhaps, majority of males still stayed in rivers or freshened sites of the bay after spawning. Fish fed weakly. Only 16,0% of specimens had food in their stomachs.

Amur stickleback This species was the most abundant and had the length of 3,7 to 9,2 cm (Latkovskaya et al., 2003). Fish 6,0 - 7,0 cm long and 1,5 - 2,5 g weigh prevailed by numbers (Fig. 3.9.25, 3.9.26). Mainly, stickleback had gonads at VI-II stages of maturity; this proved a completion of its spawning. By our observations, as a rule, a mass spawning of this stickleback takes place in July-August. Females prevailed significantly by numbers (76,1 %). The males of this species are known to stay in rivers for some time to defend spawning redds (Zyuganov, 1991). A fullness of stomachs varied from the empty stomachs to 3. 31,0 % of specimens had empty stomachs.

45,0 40,0 35,0 30,0 25,0 % 20,0 15,0 10,0 5,0 0,0 4 4,5 5 5,5 6 6,5 7 7,5 8 8,5 9 9,5 Длина, см

Fig. 3.9.25. Distribution of Amur stickleback by the length AC in the Chaivo Bay in September 2001 (n = 718)

СахНИРО Отчет по договору Y-00571 103

50,0 45,0 40,0 35,0 30,0

% 25,0 20,0 15,0 10,0 5,0 0,0 0,5 1 1,5 2 2,5 Масса, г

Fig. 3.9.26. Distribution of Amur stickleback by the body weight in the Chaivo Bay in September 2001 (n = 57)

Thus, a species composition of the Chaivo Bay ichthyofauna is formed by the freshwater, anadromous, and sea fishes. Anadromous and sea fishes prevail significantly by numbers and biomass. The typically freshwater species (Siberian stone loach and lake minnow) occurred sporadically in the bay, at its heavily freshened sites. Pacific salmon spawn in rivers flowing into the bay. A fishing of pink, chum, saffron cod, flathead sculpin and others is realized in the Chaivo Bay in small sizes. Anadromous fishes migrate through the Chaivo Bay to rivers flowing into it. Some of them (Pacific salmon, arctic lamprey) make the extensive sea migrations, the other (Sakhalin char, Sakhalin taimen, Asiatic smelt, pond smelts H. nipponensis and H. olidus, Pacific redfins, sticklebacks) inhabit the bay for a long time during a year. Periodically, the latter species move out of the bay to the open part of the sea. Specimens of almost all size-age groups of these species occur in the bay during a year. Three groups may be distinguished among sea fishes. The first group includes species inhabiting the bays during a long period of life: flathead sculpin and banded flounder (almost all age-size groups occurred during the study period). The second group includes species, which juveniles feed in bays, and adult specimens enter the bays seasonally in mass numbers: herring, saffron cod, starry flounder, Pacific eelpout. The third group includes species periodically enter the bay: greenlings, gunnels, tubenose poacher, Steller’s sculpin, Alaska plaice. The results of the Chaivo Bay survey prove spawning the juveniles of the main (in the northeastern part of the island) marine commercial fishes: saffron cod and starry flounder. During the study period in September 2001, the greatest biomass in the Chaivo Bay was recorded for pond smelts and Pacific redfins; of commercial fishes, a relatively high biomass was at saffron cod and starry flounder. It should be noted that biomass of many fish species in the Chaivo Bay changes significantly during a year. This is related, first of all, to the anadromous species making the extensive sea migrations: Pacific salmon, arctic lamprey, and some marine fishes, which enter the bay episodically. Biomass varies less significantly at such anadromous species as Sakhalin char, Sakhalin taimen, pond smelts (H. nipponensis, H. olidus), sticklebacks, and others. Biomass varies insignificantly at marine species (flathead sculpin, banded flounder) occurring in the bay during a long period of life. For saffron cod, this index, evidently, changes significantly due to the abundance of its young generations.

СахНИРО Отчет по договору Y-00571 104 4. NYISKY BAY

4.1. General physic-geographic characteristics of the Nyisky Bay

The Nyisky Bay is located between 51°50′ and 52º10′ N. The bay extension is about 44 km, maximum width 6.5 km, area 110.9 km. The bay is a common coastal semi-open lagoon, separated from the sea by two low-lying woodless spits, the southern of which is named Plastun. The Island of Gafovich is located between the spits. The bay is joined with the sea by two straits. The southern channel located between Cape Takrvo on the Gafovich Island and Cape Are on the Plastun spit is named the Anuchin Strait. The width of the strait is about 1.5 km, depths from 1.5 to 3 m. The northern channel is much narrower – about 300 m, depths from 3.5 to 5.5 m. By its morphogenetic type, Nyisky Bay is a lagoon-estuary. This is well seen from the bathymetric scheme. Erosive narrows, crossing the bay, are in fact the continuation of riverbeds flowing into it. Geographically, the Nyisky Bay is divided into two parts: bays Nyivo and Dagi. A dividing boundary passes approximately along the northern extremity of Gafovich Island. The main fairway of the Nyisky Bay passes along the Plastun spit, joining to the channels of Tym River near the Krotovsky Island. Branches of the main fairway pass through the central part of the bay in the direction of channels Chemerny and Mopi on the southern coast. Another branch is directed to the west toward the mouths of rivers Bolshaya Veni and Malaya Veni. In the Dagi Bay the main fairway passes along the Gafovich Island and northern spit toward the channel to the Chaivo Bay. The fairway’s branches pass between the islands Kaurunani and Larvo, moving to the mouths of rivers Tomi, Dagi, and Tapauna. Depths on the fairway are from 1.5 to 3.0 m. Due to the relative narrowness, a basin of the proper bay is weakly expressed; this is especially related to the Dagi Bay. The bottom is a plain with depths less than 1 m. During the ebb, a great part of bottom is being dried. The western shore of Nyisky Bay is high and covered with wood. The eastern shore is low and sandy. Southern and northern coasts are also low, covered with peatbogs and swamped in some places. A hydrographic net is mostly developed in the southern and western parts of the bay. In the south a delta of Tym River (the largest at Sakhalin) is located. In the west, many brooks and rivers flow into the bay. The rivers Bolshaya and Malaya Veni, Bauri, Nelbuta, Tomi, Dagi, and Tapauna are the largest. The mouths of rivers and brooks of the western coast are weakly branched; they are like swamped plains. In the north, the Malaya Tapauna Brook flows into the bay (Ecological studies…, 2001). Sedimentary, volcanogenic-sedimentary, and metamorphosed rocks of Mesozoic and Cenozoic ages take part in the geologic construction of the Nyisky Bay region. The bay’s bottom and shores are formed by the Quaternary rocks of the upper-Quaternary and modern links. As far as the rivers flowing into the bay drain the vast areas, we somewhat widen a described region in order to embrace more completely a contribution of different sources forming biogeochemical conditions of the areas. G.V. Polunin and his colleagues (Polunin et al., 1991) have distinguished 5 main lithologic complexes in the northeastern Sakhalin based on the geologic construction of the surface layer of lithosphere; of them, 5 complexes occur in the water basins of rivers flowing into the Nyisky Bay. Complex I includes loose Quaternary depositions (marine, alluvial, and alluvial- proluvial) related to the upper link of Pleistocene and Holocene. The depositions are represented by sands, loamy sands, and gravel with rare pebble and detritus on the unbound strata (rivers’ flood-lands and beds); in bays they are represented by silts, and loamy sands; on the semi-rock strata by small-sized and coarse pebble and rubbles. This complex forms the plain bottoms of large rivers (Tym, Dagi), and the bay bottom and shores. Low flood-land terraces, shore swells interleaving with the swamped sites, debris cones in the river and brook mouths, and zones of dewatering are here the main forms of relief.

СахНИРО Отчет по договору Y-00571 105 Complex II consists of the Nutovsky and mid-upper-Daginsky suites; it is widely distributed in the water basins of rivers flowing into the Nyisky Bay and represented by strata having a high level of filtration: sandstone (mainly, small- and medium-grained on the clay cement) with rare pebble and occurrence of clay interlayer. Subterranean waters play a dominant part in the relief formation on these strata. Here, a plateau-form relief is developed. Complex III consists of the Okobykaisky, Uyninsky, and Khuzinsky suites. It is represented by clay, aleurites, argillites with the intermediate layers of sandstone and coals. These strata are in low filtration ability and high level of soaking. There is a high surface run-off and developed erosive relief with the deeply incised river plains. This complex is rare and occurs in water collections of the rivers flowing into the Nyisky Bay. Complex IV includes the low-Daginsky suite and is represented by the following strata: sandstone (mainly quartz), argillites, siliceous aleurolite, tuffsandstone, and coals. The intensively divided relief is formed here. It occurs rarely. Complex V is presented by the Tsaekhuryinsky suite. This complex forms low-powered basal layers; it occurs rarer than others. It is formed, predominantly, by aleurolites flasks, homogenous siliceous clays, and in some places contains much sand material. A relief is mountainous and strongly divided. The bay shores are formed by the Quaternary rocks represented by the alluvial depositions; a river water collection is represented by the complex of neogenic rocks (mainly, Nutovsky, Daginsky, Okobykaysky, and Daekhurinsky suites). Podzol soils are distributed on the major territory of the study region. They are formed on loose, poor in chemical and mineralogical respects, well filter strata, and on sea dunes, low shore, and low watershed (100 m above a sea level) as well. Fulvo-acids prevail in the humus composition of podzol soils. The soils of region of the Tym River bed differ from the rest regions. This is connected with the geological differences, and such a phenomenon that rivers from the northern part of the study region have a predominant subterranean supply, whereas the Tym River – rainy feeding. This is related only to a summer period, whereas during a flood period, snow supply has a predominant significance for rivers from all the northeastern Sakhalin (Latkovskaya et al., 2000). A considered region is located in a zone of monsoon activity from the temperate latitudes; its peculiarity is a seasonal change in the dominating wind flows. Tidal fluctuations of the sea level influenced greatly upon the formation of the lagoon hydrodynamics regime. A wide channel and long fairways in the bay promote a penetration of tide practically over the whole bay area. In the study region the tide fluctuations have a daily character, that is, one high and one low tide are observed during 24 hours. A mean estimate of the daily tide at the entrance to the Nyisky Bay makes up about 0.9 m, the maximum estimate 1.9 m. During the tidal waves penetration to the bay along the fairway, a decrease in their amplitudes and increase in their phases take place due to the diffraction and increase in the influence of the bottom and lateral friction. The tidal wave penetration into the lagoon is accompanied with the rise of strong tidal streamline currents. These currents reach the maximum values on the main fairway, directly at the bay outlet. By the measuring data, their mean values constitute 0.5-0.7 m/sec, and maximum values reach 1.5 m/sec. The influence of the tidal currents upon the hydrodynamics conditions of the bay is localized in the region of the channel and fairways. Moving off them, the periodic currents are weakened and become hardly noticeable in the shallow zones. Besides the tidal phenomena, a sea influence on the hydrodynamics regime of the Nyisky Bay is reflected in stormy raising of the water level. The raising origination is caused by meteorological phenomenon: the influence of atmospheric pressure and wind on the sea surface. The greatest raisings are observed in October-November and February-March, caused by the profound cyclones passing above the Okhotsk Sea in this period. Their estimates may reach 0.5- 1.0 m in this period. As a rule, the raising duration makes up more than 12 hours. During this time period a great volume of seawater enters the bay caused by the activity of the pressing

СахНИРО Отчет по договору Y-00571 106 wind. After stopping the activity of factors provoking the raising of the water level, the accumulated water mass flows to the sea out of the bay grasping solid material. As a rule, the raising effect is strengthened by the influence of a rough sea. The active dynamics of the straits causes a constant change in their location. A northern shore of the Anuchin Strait is being intensively eroded, shifting to the north with the mean velocity of 20.7 m/year. A southern shore is being inwashed, however, a velocity of its grow is behind the velocity of its erosion. That is why, a series of small islands and shallows was formed in the strait. During the 1999 survey, a large sandy island dividing the channel into two branches was recorded in the middle of Anuchin Strait. A northern channel has been shifting to the south with the mean velocity of about 26 m/year since 1952 through 1979. No shifting has been revealed since 1979 through 1985, and in 1986 the strait has shifted to the north 240 m more. Along with the change in location of the bay outlets, the location of fairways is exposed to significant changing. It is affected both by the tide processes and river run-off, especially during a spring flood. A river run-off affects mainly in the southern part of the bay (delta of Tym River), and also in places of inflowing of the smaller rivers on the western coast. The affect of the river run- off is the greatest during a spring flood, the peak of which occurs, as a rule, in the second half of May. In this time period the mean estimates of the water rise in rivers Tym and Dagi reach 2.7 m; the water occurrence on flood-plain is observed. A period of the spring flood is accompanied by the active flowing of fresh waters and terrigenous run-offs into the bay. In the rest time, including summer and winter low water levels, the water level in rivers do not change significantly, and the volume of water flowing to the bay practically remains invariable. The mean annual volume of water exported by the Tym River constitutes more than 2.6 billion m3 a year, the mean annual sediment run-off is more than 200 thousand tons. Analogous indices for the Dagi River constitute 345 million m3/year and 7.6 thousand t/year, respectively.

4.2. Hydrology and hydrochemistry of the Nyisky Bay

4.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data Archive data on the Nyisky Bay include the materials on the state of ecosystem and oil pollution by the results of the 1995-1996 monitoring (Velikanov et al., 1996), results of monitoring studies in lagoons and coastal zone of northeastern Sakhalin in 1995-1996 (Samatov et al., 1997), and materials obtained during the joint scientific expedition of SakhNIRO – “Ecological Company of Sakhalin” in June-July 1999 (Latkovskaya et al., 2001; Ecological studies…, 2001 г.). Data on hydrologic-hydrochemical regime, particle-size composition of bottom sediments and pollutants occurring in them are practically absent in literary. Some published literary sources consider only individual components of the bay ecosystem: physic- geographic conditions, studies of benthos and fish communities, and some data on anthropogenic pollution (Brovko, 1990; Krasavtsev, 1991; Kafanov ,1984; Churikov, 1978). A temperature regime of the lagoon is determined by the seawater flow through the channels, radiation warming, and in-shore run-off (Ecological studies…, 2001). A spatial distribution of hydrologic characteristics also changes significantly due to the tide phase. Being carried out during different phases of tide, hydrologic surveys performed by SakhNIRO in June-August 1995-1996 allow considering these changes. A daily tide with high waters coming at 7-12 a.m. and low waters coming from 16 to 23 p.m. was observed. The days of surveys can be considered in the following order in connection with the time of high and low waters: 1. 19.06.95 – on the tide 2. 16.06.95 - 2 hours after the tide coming 3. 21.06.95 - 4 hours after the tide coming 4. 14.06.95 - 5 hours after the tide coming

СахНИРО Отчет по договору Y-00571 107

5. 23.06.95 - 1 hour before the low tide (water) coming. Such approach to the analysis of thermohaline structure of the Nyisky Bay allows watching a daily dynamics of waters and their transformation. On the tide, seawaters being distributed first over the bottom of the deep part of the bay underlay the river run-off and, having no opportunity to move farther to the south, spread over the bottom of the more shallow part. Salt and cold seawaters ( S>28 ‰,T<5 °С ) occupy on the tide almost a half of the bay near the bottom. The freshened surface waters are being displaced to the shallow eastern part, where salinity does not exceed 16 ‰ and temperature is not lower than 10 °С. Further, there is an active confusion of waters with their transformation. Changes begin from a surface, and the area occupied by the freshened water increases two times. A total picture of distribution of hydrologic characteristics has been changing: a meridional location of isotherms and isohalines on the surface is replaced by the latitude one; conversely near the bottom. Temperature and salinity gradients at the near-mouth site decline, and the maximum gradients at the surface have been shifting to the strait. On the ebb, a total bay from surface to bottom is filled up with freshened water of < 16 ‰ salinity and > 10 °С temperature. In a simplified view a hydrologic regime of the Nyisky Bay is determined by the inflow of cold seawaters through the Anuchin Strait on the tide, warm river waters on the ebb, and their confusion. In order to control a process of confusion, changes in hydrologic characteristics in the near-bottom layer at a station closest for the strait are the best phenomenon for considering. Taking into account the following TS characteristics: seawater - T=3.60 °С, S=30.79 ‰, river water - T=12.39 °С, S=0.04 ‰, by the elementary computation using TS-characteristics of the minimally confused waters (T=8.79 °С, S=19.39 ‰), we may conclude that on the ebb the maximum content of seawaters in the bay does not exceed 50 % (Zverkova et al., 1997). Regime of water salinity in the bay is determined by the united affect of marine tides and river run-off. The water with more than 20 ‰ salinity in the surface horizon penetrates only into the northeastern part of the Nyivo lagoon. Moving away from the fairways, salinity decreases reaching 4-10 ‰ in the southeastern part of the bay, and 8-12 ‰ in its western part. In the near- bottom layer seawater penetrates practically up to the mouth of Tym River along the fairways. Moving away from the fairways, salinity decreases up to 12-16 ‰. In the Dagi lagoon, where the influence of the river run-off is significantly lower, water with more than 20 ‰ salinity, both at surface and near bottom, penetrates practically all over the bay area. Decrease in salinity up to 10-16 ‰ is recorded only in small bays in places of rivers’ inflow. A vertical salinity distribution in the Dagi lagoon is homogeneous: differences of salinity estimates at surface and near bottom do not exceed 2-4 ‰. This is realized under the active water dynamics promoting a good confusion. On the major part of Nyivo lagoon salinity contrasts constitute 2-4 ‰. However, in the southeastern part of the lagoon their estimates increase to 12-14 ‰, and at individual stations exceed 20 ‰ under the influence of Tym River run-off and penetration of seawater along the fairways. A stagnant zone in the central part of Gafovich Island formed under the influence of tides penetrating to the bay through the southern and northern channels is of special interest. There, due to the extremely weak water exchange, a special water mass with salinity common for seawaters and temperature common for coastal shallows was formed (Ecological studies…, 2001). Studies, conducted in June-August 1995-1996, embraced, mainly, the southern part of the bay in regions with fishery camps and river mouths; in the northern part only one station located near the mouth of Dagi River was performed. A total of 10 stations were performed in June 1995, and 13 stations in June 1996. Concentrations of biogenic elements in the bay water samples were rather high and varied widely: nitrates - from 7.60 to 8.80 mkg/dm3; nitrites - from 0.00 to 60.80 mkg/dm3; ions of ammonium – from 1.47 to 14.25 mkg/dm3; phosphates – from 0.00 to 1861.75 mkg/dm3; silicon – from 186.00 to 1069.50 mkg/dm3. In June-July 1999, a total of 12 hydrochemical stations were performed. Water samples were taken both in the phase of tide and in the phase of “stop-water” (end of ebb – beginning of

СахНИРО Отчет по договору Y-00571 108 tide), when water had characteristics of “lagoon”. That was why, the obtained estimates clearly reflected a picture of tide behavior and phase of tide. Statistic parameters of hydrochemical indices of the Nyisky Bay water are given in Table 4.2.1. Maximum levels of content of dissolved oxygen were recorded at stations located along the fairway close to the strait (near Bayandin Island) and those performed during different phases of the tide. Minimum concentrations were observed in the channel between the bays Dagi and Chaivo, and also at the mouth sites of rivers during the ebb and beginning of tide. Cold seawaters (11.0-12.0 mg/dm3) were the most saturated with oxygen, river waters (8.0-9.0 mg/dm3) the 3 least. The content of О2 was 9.0 -10.0 mg/dm in water at the phase of confusion (ebb-tide).

Table 4.2.1 Statistic parameters of hydrochemical indices of the Nyisky Bay water in June-July 1999 Index Хav. σ min max Dissolved oxygen, mg/dm3 9.86 1.77 7.60 12.96 3 BOD, mg O2/dm 2.88 1.34 0.93 4.82 3 COD, mg O2/dm 4.94 1.86 1.70 7.14 Phosphorus general, mkg/dm3 27.64 11.47 7.50 42.50 Рhosphorus (orthophosphates), 20.50 7.78 15.00 26.00 mkg/dm3 Phosphorus organic, mkg/dm3 15.50 0.71 15.00 16.00 Silocon, mkg/dm3 3731 2798 700 8050 Chlorophyll a, mg/dm3 4.73 3.14 1.25 12.33 Susp. matters, mg/l 33.1 39.8 10.5 171.3

The maximum estimates of BOD5 were recorded at the mouth sites of rivers and central parts of the bay, in zones of accumulation of the thin suspended matters. A direct dependence between the content of thin fractions and BOD5 was observed. A ratio between BOD5 and COD (chemical oxygen demand) varied from 0.13 to 2.61, averaged 0.88; this proved insignificant concentrations of non-persistent organic matter. The maximum estimates of demanded oxygen were timed to stations with a high content of thin ground fractions. There was not a clear dependence of COD on the tide phase, although a weak increase in this index at the phase of “stop-water” was watched. The major part of phosphorus in the Nyisky Bay water was constituted by the mineral form as orthophosphates. The maximum silicon contents were recorded in samples collected at the phase of the end of ebb – beginning of tide and having 5-10 ‰ salinity. There the ground was represented by rather large fractions. A high content of silicon was caused by the greatest influence of river waters. The minimum estimates were recorded at stations with high salinity (29-30 ‰), when seawaters were the most affective. The maximum estimates of suspended matters were recorded at the mouth sites of rivers and timed to regions with the lower depth and high content of sediment thin fractions. The minimum estimates were observed at stations on the tide. A daily distribution of dissolved oxygen and BOD5 in the Nyisky Bay was in concordance with the tide run (a decrease at low tide and increase at high tide were observed for О2 and BOD5 concentrations); this was a consequence of inflow of the new seawaters (rich of oxygen) into the bay during a tide and outflow of the freshened lagoon waters during an ebb. A daily distribution of the examined phosphorus forms (Рgeneral, Рorganic, Р-РО4) and suspended matters directly depended upon the tide run too. The decrease in concentrations of all the phosphorus forms and suspended matters in water was observed during the tide, and increase during the ebb. This is in concordance with the inflow of river waters (rich of phosphorus) during the ebb, and poorer seawaters during the tide. A daily distribution of silicon

СахНИРО Отчет по договору Y-00571 109 concentrations depended upon the tidal run in the bay less clearly; this is connected with a strong confusion of lagoon waters during sampling.

4.2.2. Results of hydrologic-hydrochemical researches in 2002 Results of hydrologic-hydrochemical analysis of samples from the Nyisky Bay are given in Appendix 4.2.1. Some statistic characteristics of the determined parameters are reflected in Table 4.2.2.

Table 4.2.2 Some statistic characteristics of the determined ingredients from the Nyisky Bay in 2002 Ingredients Xav Xmax Xmin Depth, m * 6.0 0.4 Temperature, ºС 9.8 13.2 6.6 Salinity, ‰ 16.0 29.4 2.4 pH value 8.23 8.69 7.67 Dissolved oxygen, mg/dm3 10.26 12.00 8.99 Nitrogen nitrite, mkg/dm3 < 0.5 1.5 < 0.5 Nitrogen nitrate, mkg/dm3 14.3 37.0 < 5.0 Phosphorus (orthophosphates), mkg/dm3 20.2 75.3 6.0 Silicon, mkg/dm3 917.9 1776.4 455.2 Mass concentration of petroleum products, mg/dm3 < 0.005 < 0.005 < 0.005 Suspended matters, mg/dm3 13.69 33.13 7.80 Chlorophyll а, mkg/dm3 2.15 9.61 0.90 • Insufficient data for a statistic processing

A gradual increase in water temperature from northern stations to southern ones was watched during its distribution over the bay area. The maximum estimate was recorded at the most shallow station 6 in the center of the bay (depth 0.2 m), minimum at the very northern station 1, despite its shallow waters (depth 0.4 m). The mean water temperature during sampling was 9.8 ºС. Seawaters and Tym and Dagi rivers’ run-off affected a salinity distribution. That is why, the maximum salinity estimates were observed at stations located in the center of the bay in a zone of the seawater influence (4-8), and from the center to the northern and southern stations (1-3 and 9-12) a gradual decrease in salinity was observed. The mean salinity estimate of the Nyisky Bay was 16.0 ‰. A distribution of pH value over the bay area repeated, in general, a salinity distribution (a tendency to the decrease in pH was watched from the center to the northern and southern stations). The maximum pH estimate was recorded at station 4 (8.69), minimum at station 11 (7.67). The mean pH estimate from the bay water samples was 8.23. Concentrations of dissolved oxygen ranged widely from 8.99 to 12.00 mg/dm3 (a near- bottom horizon of station 7, and station 5). The mean concentration over the bay was 10.26 mg/dm3. We could not reveal a definite character for oxygen distribution both by area and by depth. A content of nitrite nitrogen in water samples was minimum in major cases, concentrations occurred below the method sensitivity (< 0.5 mkg/dm3). Nitrite nitrogen was found only in samples at deep-water stations (4, 7, 8), located close to channels joining the bay and the sea; this was caused, probably, by the intensive processes of production and consumption - 3 in places of sampling. A content of N-NO3 was 0.9 – 1.9 mkg/dm . The mean nitrite concentration was 1.5 mkg/dm3. A content of nitrate nitrogen ranged widely from the minimum estimates <5.0 mkg/dm3 (below the method’s sensitivity) to the maximum one (37.0 мкг/дм3). The minimum estimates were found in water samples at stations 1, 2, 3, located in the northern part of the bay, maximum at stations 4, 7, located near the channels. In the southern part of the bay being influenced by the СахНИРО Отчет по договору Y-00571 110 Tym River run-off (salinity from 2.4 to 6.9 ‰; stations 11, 12, respectively), concentration of - - 3 N-NO3 was also rather high (24.0 – 29.0 mkg/dm ). 3 Concentrations of phosphorus constituted 6.0 – 75.3 mkg/dm , silicon 455.2 – 1776.4 mkg/dm3, averaged 20.2 and 917.9 mkg/dm3, respectively. A distribution of phosphorus and silicon over the bay area was uneven; we did not succeed in revealing its definite character. The maximum phosphorus concentration was found at station 3, minimum in the surface horizon of station 7. The maximum silicon estimates were recorded in samples at stations 10, 11, 12), located under the influence of terrigenous and river run-offs (rivers Tym and Dagi) at the deep- water stations near the outlet of the bay (7 and 8). Analysis of the Nyisky Bay water samples for petroleum hydrocarbons content did not give positive results, concentrations occurred below a threshold of detectability of the method (< 0.005 mg/dm3). A distribution of suspended matters in the bay water samples was heterogeneous, concentrations occurred in the range of 7.80 to 33.13 mg/dm3 (station 11 and a near-bottom horizon of station 8, respectively); the mean estimate was 13.69 mg/dm3. The mean estimate of chlorophyll a concentration was 2.15 mkg/dm3, varying widely from 0.93 (stations 2 and 3) to 9.61mkg/dm3 (station 1). A significant increase in concentration from surface to near-bottom horizons was observed in the distribution of both suspended matters and chlorophyll a. One can see that by the results of studies, seawaters, and terrigenous and river run-off influence significantly upon the size and distribution of determined hydrochemical parameters. Estimates of concentrations of all the determined ingredients were within the standard or much lower than the tolerance limit concentrations (List of fisheries standards …, 1999); often the concentrations of determined parameters were below a threshold detectability of the method.

4.3. Particle-size composition of bottom sediments in the Nyisky Bay

In June-July 1999, during the joint scientific expedition of SakhNIRO – “Ecological Company of Sakhalin”, a particle-size composition of bottom sediments was studied at 49 stations. By the study results, statistic parameters of content of the particle-size fractions in the surface layer of the Nyisky Bay bottom sediments are given in Table 4.3.1.

Table 4.3.1 Statistic parameters of content of the particle-size fractions in the surface layer of the Nyisky Bay bottom sediments in July 1999 (n=49, in %) Fraction Xav σ Median Mode Min Max > 1 mm 2.61 6.08 0.00 0.00 0.0 73.3 1-0.5 3.8 5.0 1.9 1.8 0.0 24.6 0.5-0.25 23.5 20.7 16.3 11.7 0.4 83.6 0.25-0.1 27.3 18.9 25.8 35.2 2.1 73.6 0.1-0.05 9.9 12.7 5.3 0.3 0.2 49.3 0.05-0.01 19.7 18.4 15.3 0.0 0.0 53.4 0.01-0.005 6.83 6.11 6.15 0.00 0.00 24.2 0,005 4.74 4.69 2.90 0.00 0.00 17.3

A distribution of fraction sizes of the bottom sediments was noted to be in concordance with the picture of the tide and river freshwaters behavior. The maximum content of sediment coarse fractions (gravel and coarse sand) was observed along the Nyivo spit, near Cape Bauri, and in the mouth of Dagi River. These regions are related to transit zones, where a thin fraction, being outflowed by rivers, does not remain. A distribution of medium sand fraction (besides the above transit sites) included some more regions with a noticeable dynamics: along the northern

СахНИРО Отчет по договору Y-00571 111 spit and at the outlet of the bay (straits Dagi and Anuchin). A distribution of aleuro-pelite fractions showed the occurrence of zones of accumulation in the mouth zones practically of all the large rivers, except for Dagi River. In general, a small-aleurite fraction (34.7 %) prevailed; a proportion of fine and medium sand fractions constituted by 16.0 %. Coarse fractions showed the minimum estimates. All ground types were presented in the bay: from graveled sand to loamy silts. The most coarse sediments were observed near the mouth of Dagi River, near Cape Bauri, and along Nyivo bar, the most thin grounds were recorded in the mouth regions of the rest rivers and in central part of the bay, connecting Nyivo and Dagi bays. The main factors of reforming the bottom relief and formation of the Nyisky Bay bottom sediments have been characterized. Tidal phenomena, autumn raisings of the water level, river run-off, and biological processes were recognized to be these main factors. Tidal phenomena influence upon the total area of this water body. Raisings of the water level caused by the autumn storms play a great part in exporting materials and changing the bottom and shore relief of the Nyisky Bay. The material brought by rivers forms debris cones, which create delta, and is a source of silty sediments not spreading for long distances from the mouth, since the river inclinations are insignificant, and their current velocities are not high (except for Tym River). Flood phenomena play a significant part in the Nyisky Bay ground formation, since the Tym River originates from the East-Sakhalin Mountains and has a great water collection. A biogenic factor contributes greatly to the formation of bottom sediments in places of development of Zostera fields. In such places the ground is represented by silts with the grass remains in different stages of decomposition. Tidal phenomena affect, to the great extent, the channels and adjoining sites of the bay accumulative plains. A river-run-off, biogenic factor, and wind are the main conditions forming bottom sediments directly of the bay basin. It has been concluded that a complex interaction between the sediment-forming factors leads to differentiation of the sediment material and formation of different types of bottom sediments on the area of Nyisky Bay: sands of different sizes (from coarse to fine) prevail along the river narrows of run-off and tidal fairways, small particles deposit on the river debris cones; aleuro-pelite silts with a low content of pelite and subcolloidal particles, mainly, of biogenic origin are observed in the regions of Zostera and other water plants growing.

4.4. Content of pollutants in the Nyisky Bay

4.4.1. Content of pollutants in bottom sediments by the archive and literary data Petroleum hydrocarbons A content of PHC by the materials of 1995-1996 was determined in the experimental center of DVGAU “Ocean” by the method of infra-red spectrometry using the device «Specord- 85» (Temporary methodic recommendations…,1984 г.). PHC concentrations varied from 0.3 to 17.3 mkg/g of the dry weight in June 1995. The minimum content was recorded in the southern part of the bay, not far from the mouth of Tym River, maximum in the northern part of the bay near the mouth of Dagi River. Concentrations of aromatic hydrocarbons varied from 0.02 to 3.3 mkg/g, averaged 0.58 mkg/g; aliphatic hydrocarbons from 0.32 to 15.01 mkg/g, averaged 6.87 mkg/g, that is, exceeding those of aromatic HC 12 times. The maximum estimate of aromatic HC was recorded in the Anuchin Strait joining the bay with the sea, aliphatic HC in the region of Veni River, where the ground was represented by silty sand. It was noted that maximum concentrations of aromatic and aliphatic hydrocarbons were found in the silty grounds along the bay fairway. Data of studies indicate a dependence between the type of ground and content of HC in it. Sandy ground is characterized by the higher level of purification compared to silty and pebble grounds. Components of polyaromatic hydrocarbons were identified by 43 patterns. A relatively high mean content of perilen (431.1 ng/g), phenanthrene(6.41 нг/г), and benz(b)fluoranthrene

СахНИРО Отчет по договору Y-00571 112 (2.99 ng/g) was observed. Fishery camps Medvezhiy and Nyivo and a fairway between them were the places of PAHC detection. Examined bottom sediments were referred to the relatively pure, since the total content of PAHC varied from 0.64 to 225.4 ng/g; grounds are considered to be polluted, if PAHC concentration in them reaches tens and more mg/g (Izrael, 1989; Semenov, 1996). A ratio between the “man-caused” and “natural” polyarenes (1/4; pirene + benz(a) pirene / phenanthrene + chrysene) indicated a low level of anthropogenic pollution in the bay. In addition, perilene, being originated by the natural way, was the most abundant of PAHC. A range of HC concentrations in June 1996 was insignificant and constituted 60.0 – 390.0 mkg/g of the wet weight under the mean content of 190.0 mkg/g. The maximum content was recorded in the region of the Veni River mouth and fishing camp Bauri, minimum at a station located near the spit (Nyivo). A total content of non-volatile and resinous matters ranged within 40.0 – 500.0 mkg/g. In the southwestern part of the bay the non-volatile HC concentrations were practically the same everywhere and varied within 100.0 – 170.0 mg/g. The eastern part of the bay was declared to be purer, despite the activity of fishing camps; there the concentrations of resinous matters did not exceed 24.0 mkg/g, and non-volatile 90.0 mkg/g. It was noted that sandy ground and strong water dynamics of this region played an important part in the system of purification. There was a decline in proportion of resinous matters 2 times lower from June to September practically at all stations. Intensification of destruction of this group of pollutants caused by the increase in temperature by the end of August could be the reason for such a decline. A shallow Bauri Bay (depths up to 20 cm) was a zone of the maximum man-caused load. Bottom sediments of this region were characterized by the heavy silting and content of resinous matters of 0.142 mg/g, which 2-12 times exceeded estimates in other regions. The higher concentrations of resinous matters were also common for the mouth of Tapauna River (130.0 mkg/g) in the northwestern part of the bay (a region of oil exploitation) and for the region of Gafovich Island (250.0 mkg/g); this indicated the presence of active source of oil pollution (badly conserved oil well). In June, high concentrations of pollutants (130.0 mkg/g) were recorded in the mouth of Tapauna River. In the mouth of Tomi River a proportion of resinous matters was 19 %. Bottom sediments of the mouths of Tym and Dagi rivers collected in late August contained minimum concentrations of the non-volatile HC and resinous matters; the first concentrations prevailed (50.0 mkg/g and 10.0 mkg/g). The 1995 results obtained in the specialized center of Alaska (ABL) under the exclusive adherence of the method and using a more sensitive device have proved such a picture. By the results of studies in June 1996, a total of 14 polyarenes have been identified; their concentrations ranged within 0.6 – 30.0 ng/g, on average. A total content of PAHC varied from 32.0 to 452.0 ng/g. A proportion of benz(a)pirene, compared to other components, was a little higher (9 % of the total composition); a domination of “man-caused” HC indicated the anthropogenic source of PAHC incoming. During the joint expedition in June-July 1999, a total concentration of petroleum products in the bay was determined at 10 stations and varied from 0.00 to 16.08 mkg/g. The anomalous high concentration of PHC was recorded at a station opposite the fishing camp, near the Nyivo settlement (16.08 mkg/g), at the rest stations a content of PHC in bottom sediments did not exceed 0.5 mkg/g. A spatial distribution was characterized by the higher contents of petroleum products at stations along the Nyivo spit and at the mouth sites of all the rivers. Correlation analysis revealed a high positive relation between concentrations of petroleum products and contents of gravel and graveled sand fractions (5.0–1.0 mm) and a negative relation with the contents of bottom sediments less than 0.1 mm in size; this indicated a possible presence of the anthropogenic source of petroleum products incoming.

Phenols In June 1996, phenols in the bottom sediment samples from the Nyisky Bay were found practically everywhere. Phenol concentrations varied widely from 0.5 to 8.6 mkg/g of the dry weight. The mean content was 2.96 mkg/g under the standard deviation of 2.25. The maximum

СахНИРО Отчет по договору Y-00571 113 phenol level was recorded at the outlet of the bay in the region of Bayandin Island, where a portion of silty structures of bottom sediments was significant. A comparison of levels of the phenol contents in June 1996 with the 1990-1991 studies (Krasavtsev, 1991) and concentrations in the background regions of the northern Pacific Ocean (Tkalin et al., 1991) showed the increase in phenol concentrations, which was connected with the processes of phenol accumulation in the bay bottom sediments caused by their incoming from different sources. The used method of analysis did not allow to isolate natural phenols from the man- caused ones; this did not give the possibility to reveal sources of incoming and possible causes of accumulation.

Chlororganic pesticides and polychlorinated biphenyls A content of COP in the Nyisky Bay bottom sediments varied from 0.2 to 1.61 ng/g of the dry weight and was maximum at a station located in the Bauri Bay (near the fishing camp). The mean pesticide concentration was 0.76 ng/g of the dry weight. Summarized numbers of pesticides close to 1.00 ng/g were grouped at stations near the eastern spit (0.86, 0.90, 0.98, 1.00). In the bay codend, near the inflow of Bolshaya Veni River, stations with minimum estimates (0.20, 0.21, 0.46) were grouped. Thus, two rather contrast regions were watched in the studied part of the bay. Based on the scheme of currents in the bay, the higher levels of COP accumulation in the ground along the spit were supposed to be a consequence of the Tym River run-off and its export of different pollutants. α and γ-HCCH were found in grounds everywhere. β-HCCH was found only at two stations in the Bauri Bay. A number of all three hexachlorcyclohexane (HCCH) isomers was maximum at a station in the Bauri Bay near the fishing camp. The maximum concentration of (para-derivatives) p,p-DDD constituted 0.6 ng/g of the dry weight near the mouth of Tapauna River flowing through the exploited oil-gas field in the name of R.S. Mirzoev. At 5 stations, p,p-DDT was found in grounds; its maximum number was found near the spit separating a southern part of the bay from the Okhotsk Sea. The higher concentrations of DDT and its metabolites, found at stations along the spit, prove a supposition on the affect of export from the Tym River. A total of 7 COP forms were found in the lagoon in June. In August 1996, the mean number of COP in the bay bottom sediments was 0.013 ng/g of dry weight, which was significantly lower than in June. Pesticides were found only at 7 stations, majority of which were located in the southern part of the bay; this is associated with the influence of the Tym River export. The maximum number of COP was recorded not far from the mouth of Tym River (0.06 ng/g). A qualitative composition of pesticides in bottom sediments in August was the same as in June. PCB in bottom sediments of the Nyisky Bay were found in June only in the fairway bottom sediment samples not far from the outlet of the bay; their concentration constituted 6 ng/g of the dry weight. In August they were not found. Thus, a decline in COP and PCB concentrations was watched from spring to summer. This is connected with the spring flood, large area of water collection, and terrigenous run-off bringing different matters into the bay. Then, due to the tidal activity, a redestribution of COP and their further degradation takes place. A total number of pesticides varied in 1999 from 0.0 to 3.1 ng/g and was maximum in the center of the channel joining Nyivo and Dagi bays. The mean concentration was 1.05 ± 1.29 ng/g. Statistic parameters of COP content are given in Table 4.4.1.

СахНИРО Отчет по договору Y-00571 114 Table 4.4.1 Statistic parameters of pesticide contents (ng/g) in bottom sediments of the Nyisky Bay in July 1999 (n = 10) Index α - HCCH γ - HCCH DDE DDD DDT Total COP Хav 0.00 0.22 0.09 0.47 0.27 1.05 σ 0.00 0.66 0.18 1.02 0.85 1.29 min 0.00 0.00 0.00 0.00 0.00 0.00 max 0.00 2.10 0.50 3.10 2.70 3.10

Correlation analysis did not reveal a relationship between the pesticide contents with particle-size composition, but, nevertheless, a high positive relation between COP and thin (less than 0.05 mm) fractions, and negative relation with fractions of graveled, coarse, and medium sand was observed.

Organic carbon By the results of the 1999 study, contents of organic carbon varied from 0.0 to 6.6 %. The mean concentration was 2.1 ± 2.2 %, coefficient of variation 101.5 %. In the major part of the bay concentrations of organic carbon in bottom sediments varied within 1.5 – 2.5 %. The maximum estimates (3.0 – 5.0 %) were recorded in the stagnant zones in the region of islands Larvo, Kaurunani, to the east of Cape Bauri, and in the southwestern part of the bay. The maximum concentration (6.6 %) was recorded near Gafovich Island. Formation of zones with the higher organic contents in the bay was supposed to be connected with the increase in dispersibility of bottom sediments; in the south of the bay with the influence of terrigenous run- off. In order to determine a source of the organic matter inflow, a correlation analysis of both its content and fraction composition of bottom sediments, and a depth and concentration of PHC was carried out. A high positive relation was found between the organic carbon and content of thin (less than 0.05 mm) fractions of BS (coefficient of correlation 0.74 – 0.81), and negative with the content of sand fractions. The data of analysis prove the absence of anthropogenic sources of organic inflow.

Metals In September 1995, a total of 15 samples from bottom sediments were analyzed for metal contents. The mean content of elements and the range of obtained concentrations is given in Table 4.4.2. It was noted that concentrations of all the examined metals in the bottom sediments of shore stations were lower than in grounds at the fairway stations, which was caused by their inflow to the bay area with a flood and further redistribution in accordance with the tidal currents. A hypothesis on similar ways of the element inflow and forms of their detection in bottom sediments was framed. In order to prove this, a correlation analysis of contents of these elements in grounds was carried out, and a positive result was obtained.

Table 4.4.2 A gross content of acid-dissolved forms of some metals in the Nyisky Bay bottom sediments in September 1995 (mkg/g of the dry weight) Statistic Cu Zn Mn Pb Co Ni Fe, Cr Hg Ba Cd characteristic % min 0.60 3.70 10.1 1.11 0.37 0.37 1.72 3.20 0.004 10.7 <0.1 Max 13.90 65.60 180.0 13.40 7.38 23.80 24.6 32.00 0.083 143.0 <0.1 mean 5.25 26.81 74.3 4.74 3.51 8.44 10.2 13.87 0.034 67.0 - st.dev. 4.98 21.93 60.3 3.93 2.50 8.00 7.8 7.84 0.025 39.4 -

СахНИРО Отчет по договору Y-00571 115 In June 1996, a total of 13 samples of bottom sediments were collected and analyzed for the content of metals. The mean content of elements and range of obtained concentrations are given in Table 4.4.3. In June 1996, a station located near the Bauri Bay on the littoral (higher levels of iron, cobalt, arsenic, and cadmium) and a station at the outlet of the bay (maximum indices for aluminium, manganese, zinc, and nickel) were distinguished by the gross content of metals.

Table 4.4.3 A gross content of acid-dissolved forms of some metals in the Nyisky Bay bottom sediments in June 1996 (mkg/g of the dry weight) Statistic Al Fe Sr V Mn Ba Zn Cr Ni Cu Co Pb As Cd Hg characteristic % % min 3.27 0.73 100 15.0 52 370 13.0 36 35.0 16.0 0.6 13 5.4 0.007 0.010 max 6.91 2.91 300 64.0 290 740 68.0 85 55.0 38.0 7.5 24 11.0 0.130 0.045 mean 5.89 1.67 225 36.5 156 584 40.3 55 41.7 22.2 3.9 18.5 8.9 0.057 0.022 st.dev. 1.20 0.74 60.9 16.7 60 98 20.9 14 5.62 5.8 2.0 3.2 1.9 0.038 0.009

Correlation analysis has resulted in positive relation between contents of major elements (except for cobalt), that is, all metals excluding cobalt have the same sources of incoming. The levels of cobalt content are supposed to be caused by the vital activity of microorganisms, since this element is a product of their vital activity. In July 1999, bottom sediments were examined for metal contents at 37 stations. Statistic parameters of content of the metal active forms in the surface layer of bottom sediments by the results of studies of Nyisky Bay are given in Table 4.4.4. As a result of correlation analysis, a dependence between the content of acid-dissolved forms of metals and particle-size composition of bottom sediments was revealed. This proved the fact that metal concentrations in the bay bottom sediments were determined, mainly, by one factor: sorption abilities of bottom sediments. As a result of factor analysis of the correlation matrix by the method of main components, a relation between the elements and thin fractions of ground was proved. Clasterization of the bay stations by the content of metal active forms and fractions of bottom sediments by the method of main components showed the occurrence of two clasters: one of them was represented, mainly, by medium and fine sands, another by the aleuro- pelite fractions. It was concluded that the grouping of stations in zones of accumulation and zones of transit depended upon a scheme of the tide movement. The obtained levels were low, and they were suggested to be as background.

Table 4.4.4 Statistic parameters of content of the metal acid-dissolved forms in surface layer of the Nyisky Bay bottom sediments in July 1999 (n = 37, mkg/g of the dry weight) Metal Xav. σ Median Mode Min Max Al, % 5.75 5.13 4.40 4.40 0.30 22.00 Fe, % 8.11 5.90 7.20 6.90 0.40 24.00 Mn 69.7 57.0 58.0 20.0 1.0 180.0 Zn 28.2 20.2 24.0 8.0 3.0 64.0 V 20 0.0 20.0 20.0 20.0 60.0 Cr 12.6 10.2 9.0 2.4 2.3 36.0 Ni 11.1 9.2 8.0 26.0 0.4 28.0 Cu 5.83 3.64 4.80 2.00 1.40 13.20 Pb 2.88 2.68 2.00 0.50 0.50 8.00 Co 2.92 2.29 2.00 0.40 0.40 6.80 Cd 0.09 0.07 0.05 0.05 0.05 0.30 Hg 0.010 0.004 0.009 0.006 0.006 0.021 СахНИРО Отчет по договору Y-00571 116

4.4.2. Content of pollutants in biota

Petroleum hydrocarbons in fish tissues In June 1996, a total content of HC in fish liver from Nyisky Bay varied in the united samples from 4.0 to 10400.0 mg/100 g of the wet weight (Table 4.4.5); this constituted 0.04 – 11.0 % of the lipid contents.

Table 4.4.5 Hydrocarbon contents in fish tissues from the Nyisky Bay, mg/100 g of the wet weight Sample Hydrocarbons of petroleum Hydrocarbons of petroleum and natural origin origin range mean range mean Flathead sculpin, liver 835 – 1400 1034 10 – 29 16 Saffron cod, liver 1250 1250 15 – 26 20 Yellowfin sole, liver 20 – 36 28 18 – 28 23 Starry flounder, liver 14 – 105 59.5 2.6 – 3.5 3.1 Starry flounder, gonads 4 – 15 9.5 1.4 – 2.3 1.9 Starry flounder, muscles 2 – 3 2.5 1.3 – 1.5 1.4

A level of lipid contents in fish livers was high enough (Table 4.4.6). Evidently, the more intensive accumulation of hydrocarbons takes place in organs with the greatest content of lipids. By their accumulative ability, the examined organs have been revealed to be ordered in such a way: liver>gonads>muscles. The highest concentrations of HC were found in livers of flathead sculpin (to 1400 mg/100 g of the wet weight) and saffron cod (to 1250 mg/100 g of the wet weight). In other tissues a total content of HC was significantly lower.

Table 4.4.6 Lipid contents in livers of the bottom and near-bottom fish from the Nyisky Bay in June 1996 Fish species n Lipid content, mg/g range mean Flathead sculpin 40 76 - 131 112 Saffron cod 26 156 - 165 160.5 Yellowfin sole 15 76 – 81 78.5 Starry flounder 24 76 76

A content of HC in fish liver was 2.6–29.0 mg/100 g of the wet weight (from 0.7 to 56.0 % of the total HC) (Table 4.4.7). HC concentrations in gonads (e.g. starry flounder) were lower than in liver 1.5-2 times, and in muscles - 2-23 times lower. The maximum HC concentrations were found in livers of flathead sculpin, saffron cod, and yellowfin sole: 29.0, 26.0, and 28.0 mg/100 g of the wet weight, respectively. Some differences between HC and PHC were noted in male and female tissues for starry flounder as an example.

СахНИРО Отчет по договору Y-00571 117 Table 4.4.7 Hydrocarbon contents in tissues of starry flounder from the Nyisky Bay in August 1996 (mg/100 g of the wet weight) Sex Numbers of Tissue Hydrocarbons of Hydrocarbons of specimens petroleum and petroleum origin natural origin female 10 liver 105 3.5 female 10 gonads 4.0 1.4 female 10 muscles 2.0 1.3 male 15 liver 14 2.6 male 15 gonads 15 2.3 male 15 muscles 3.0 1.5

Polyaromatic hydrocarbons in fish tissues By the results of studies in the Nyisky Bay in August 1995, the maximum concentrations of PAHC did not exceed 29.4 mkg/g. The greatest number of PAHC (16) was identified in fish liver. Among fish species, the highest content of PAHC was recorded in liver of a flathead sculpin. By the PAHC contamination, all the examined species were ordered in such a way: sculpin>saffron cod> yellowfin sole>starry flounder. A content of PAHC in fish organs and tissues is given in Table 4.4.8.

Table 4.4.8 Polyaromatic hydrocarbon contents in fish tissues, mg/100 g of the wet weight Date of sampling Species PAHC content range mean June Flathead sculpin, liver 5.0 – 29.4 17.1 June Saffron cod, liver 13.6 – 13.7 13.7 June Yellowfin sole, liver 9.3 – 18 13.7 June Starry flounder, liver 7.0 7.0 August Starry flounder, liver 7.3 – 8.2 7.8 August Starry flounder, gonads 2.5 – 8.5 5.5 August Starry flounder, muscles 1.5 – 2.0 1.8

Chlororganic pesticides and polychlorinated biphenyls in fish tissues In 1996, 8 COP forms (α-, ß-, γ-HCCH, о,p-DDE, p,p-DDE, о,p-DDD, p,p-DDD, p,p- DDT) have ben examined. A qualitative composition of COP was presented the most completely in the liver of flathead sculpin; only ß-form of HCCH was not found in saffron cod liver; 6 representatives of COP were found in the flounder liver. In general, α-HCCH dominated among HCCH isomers, and p,p-DDE among DDT metabolites. When analyzing COP and PCB contents regarding to the place of sampling, the maximum levels of accumulations were found to occur in fish tissues caught near the fishing camp MRS located on the spit (5.7 ng/g of the wet weight – a sum of HCCH isomers, 73.8 ng/g – a sum of DDT metabolites, 79.5 ng/g – a sum of COP, 28.9 ng/g – PCB by АХ-50), which were in concordance with the higher pesticide contents in bottom sediments at this site. When comparing the mean concentrations of the examined compounds, the peculiarities of their accumulation being caused, evidently, by species specific were noted. The maximum levels of accumulation were observed in the flathead sculpin liver, minimum COP and PCB in the flounder liver. A sex variability in pesticide accumulation was noted. Liver and gonads of females contained great numbers of contaminants, the contrary picture was observed in muscles. It was noted that COP and PCB concentrations were higher in June compared to August; this is associated both with seasonal changes in the metabolism processes and seasonal peculiarities of the inflow of this contaminant class to the bay area. СахНИРО Отчет по договору Y-00571 118

Chlororganic pesticides and polychlorinated biphenyls in Zostera One form of pesticides (α-HCCH) among 9 analyzed COP and 2 PCB forms was found in all the examined samples; its mean concentration did not exceed 0.07 ng/g of the wet weight.

Metals in fish tissues Species differentiation was observed in organisms when accumulating heavy metals in the liver. Higher accumulations of zinc and mercury occurred in flounder liver, and then in sculpin and saffron cod liver. By the content of copper, species were ordered in such a way: flounder > saffron cod > sculpin; by the content of cadmium and lead: flounder = saffron cod > sculpin. It was noted that flounder specimens differed by sex features when accumulating metals in their organs: contents of zinc and copper were higher in female gonads and male muscles; concentration of lead was maximum in female liver and muscles and male gonads; content of mercury was higher in all organs of males. The mean metal content in fish tissues from the Nyisky Bay is given in Table 4.4.9.

Table 4.4.9 Mean content of metals in fish tissues from the Nyisky Bay, mkg/g of the wet weight Species Tissue Zn Cu Cd Pb Hg Flounder liver 11.43 5.92 0.57 0.039 0.035 Flounder gonads 45.50 1.60 0.035 0.019 0.011 Flounder muscles 3.31 0.62 0.007 0.009 0.032 Flathead sculpin liver 7.0 2.0 0.19 0.035 0.015 Banded flounder liver 5.6 3.7 0.06 0.028 0.03 Starry flounder liver 8.6 7.5 0.055 0.045 0.035 Saffron cod liver 5.1 6.5 0.027 0.051 0.015

Metals in Zostera tissues By the results of the 1996 studies, metals were ordered in the following way by their contents in Zostera: Zn > Cr > Cu > Cd > Pb > Hg. The mean contents of metals in the bay Zostera were as follows: Zn – 1.8 ng/g of the wet weight, Cu – 0.96 ng/g, Hg- 0.007 ng/g, Pb - 0.10 ng/g,Cd – 0.36 ng/g, Cr – 1.3 ng/g.

4.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002

Results of analysis of the bottom sediment samples for the content of petroleum products in the Nyisky Bay are given in Table 4.4.10. As one can see from the given Table, the estimates of petroleum hydrocarbons (PHC) from the bottom sediment samples of Nyisky Bay are distributed very unevenly and varied widely from < 0.5 to 41.1 mkg/g. The maximum estimate was recorded at a shallow station 5 (0.35 m), minimum at deep-water stations 7 and 8 (4.5, 6.0 m). In general over the bay, except for station 5, PHC concentrations did not exceed 11.5 mkg/g. The definite regularities for the petroleum products distribution in bottom sediments were not found. The analysis of results of the quality control has shown that % of the duplicate divergence and % of the extraction of ersatz standard did not exceed the tolerance criteria of quality.

СахНИРО Отчет по договору Y-00571 119 Table 4.4.10 A summarized concentration of petroleum products in samples of bottom sediments in 2002 and results of the analysis quality control № st Concentration of Mean divergence of Extraction of ersatz standard,% petroleum products, duplicates, % mkg/g Mean Relative standard deviation 1 1.53 31 98 11 2 4.69 3 5.55 4 7.43 5 41.1 6 5.73 7 < 0.5 26 82 14 8 < 0.5 9 2.16 10 11.5 11 2.24 12 0.93

4.5. Microbiological researches in the Nyisky Bay

Studies of microbe water cenoses in the Nyisky Bay were carried out in 1996, 1998, 1999, and 2000. Samples for microbiological analysis were taken in the autumn-summer period. In late August 1996, a total of 4 water samples were taken in the Nyisky Bay. Samples were examined for abundance (indices) of the following organisms: saprophyte heterotrophic bacteria growing on RPA, marine heterotrophic organisms developing under different water salinity (habitat of Yoshimitsu-Kimura); sanitary-indicative bacteria (bacteria of the group of enteric bacillus (BGEB) and pathogenic enteric bacteria (PEB)) (habitat of Endo, Ploskirev); petroleum-oxidizing, phenol-resistant, and metal-resistant organisms (habitat of isolation contained 0.01 % of metal): destructors of biopolymers - proteolytic and lipolytic bacteria. Indices of heterotrophic microorganisms characterizing biological pollution were as follows: marine heterotrophic microorganisms – 105 – 107 cell/ml, saprophyte heterotrophic microorganisms growing on RPA – 103 – 106 cell/ml, lipolytic bacteria – 103 -104 cell/ml and и proteolytic bacteria – 104 - 105 cell/ml (Table 4.5.1). A number of phenol-resistant microorganisms was determined only at one station. It was 102 cell/ml. Numbers of petroleum-oxidizing microorganisms varied within 102 –104 cell/ml. A microbe analysis showed that the occurrence of metal-resistant bacteria in water was recorded for all stations. A high content of Pb-resistant microorganisms was observed at station 7 (10 %) and station 6 (22 %). A content of metal-resistant forms was lower at stations 4 and 5 (7 and 3 %, respectively). For nickel, microbe indices demonstrated a wide scatter of data of the relative numbers: from 102 to 107 cell/ml. A percentage of Cu- resistant microbe forms in water of the surveyed stations was not high in general and presented by tenth and unity. A similar picture was for Co-resistant microbe distribution. Cadmium-resistant microorganisms were either absent in water samples (stations 4 and 6), or their numbers were insignificant (0.001 % at station 7). The maximum estimate (2.5 %) of these microorganisms was recorded in water sample at station 5 in the region of fishery camp and in the place of the inflow of Bolshaya Veni River. The maximum indices of abundance occurred at Zn- and Ni-resistant forms of microorganisms (106 – 107 cell/ml).

СахНИРО Отчет по договору Y-00571 120 Table 4.5.1 Numbers of colony-forming microorganisms in seawater in the Nyisky Bay in 1996, cell/ml Groups of microorganisms Station 4 5 6 7 Marine heterotrophic 106 105 106 107 Saprophyte heterotrophic 103 103 106 104 BGEB 105 103 103 105 PEB 104 -* 0** 0 Phenol-resistant 102 0 0 0 Petroleum destructors 103 102 104 Lipolytic 104 - - 103 Proteolytic 105 104 105 - Fe- resistant 105 104 105 103 Cu- resistant 105 105 105 104 Ni- resistant 103 102 106 107 Co- resistant 103 104 103 - Zn- resistant 106 105 105 106 Pb- resistant 105 104 105 106 Cd- resistant 0 104 103 104 *(–) - indefinite **(0) – absence of growth

Indices of sanitary-indicative microorganisms were rather high. Such abundance of this group of microorganisms is common for the coastal waters exposed to the anthropogenic impact due to the economic activity. When studying a structure of the water microbe cenosis in the Nyisky Bay in September 1998, a total of 3 water samples were collected (conditionally named stations 1, 2, 3). Numbers of the following physiological groups of aerobic heterotrophic colony-forming microorganisms were determined in water: saprophyte heterotrophic bacteria growing on RPA, marine heterotrophic organisms developing under the different water salinity (habitat of Yoshimitsu- Kimura); sanitary-indicative bacteria (bacteria of the group of enteric bacillus (BGEB) and pathogenic enteric bacteria (PEB)) (habitat of Endo, Ploskirev); petroleum-oxidizing, phenol- resistant, and metal-resistant organisms; destructors of biopolymers – amylolytic, proteolytic and lipolytic bacteria. A content of saprophyte heterotrophic bacteria in the examined water samples from the Nyisky Bay stations in 1998 was heterogenous. The maximum number of this group of microorganisms was recorded at a station in the mouth of Tym River (105 cell/ml), where the export of organic matters coming from the territory of the river water collection and with the economic-domestic discharge of settlement Nogliki took place. Two other samples were characterized by the lower number of this group of microorganisms and were similar (103 cell/ml) . A number of marine heterotrophic bacteria adapted to the salinity gradient was 104 - 105 cell/ml. The occurrence of sanitary-indicative microflora (bacteria of the group of enteric bacillus) was found only in the sample taken from the mouth of Tym River not far fron settlement Nogliki. Indices of petroleum-oxidizing microorganisms corresponded to the chronic level of sea oil pollution common for the navigation areas and constituted 104 - 105 cell/ml; a number of phenol-resistant microorganisms ranged within 102 - 104 cell/ml (Table. 4.5.2). A relative abundance of microorganisms- destructors of biopolymers (one or several forms simultaneously) was rather high. Thus, numbers of proteolytic and lipolytic bacteria constituted 13.95% and 27.3%, respectively of the total number of heterotrophic microorganisms. A number of amylolytic bacteria was determined only in one sample and constituted 22,05% of the total number of heterotrophic microorganisms. СахНИРО Отчет по договору Y-00571 121 Table 4.5.2 Numbers of physiological groups of the aerobic saprotrophic microorganism community in the Nyisky Bay seawater (cell/ml) Physiological groups of Nyisky Bay microorganisms st.1 st.2 st.3 Marine saprotrophic 105 105 104 Heterotrophic 105 103 103 BGEB* 70 0** 0 Pathogenic 30 0 0 Phenol destructors 104 103 102 Oil destructors 104 105 104 * bacteria of the group of enteric bacillus **(0)- absence of growth

The most probable reason of activity of this group of microorganisms is decomposition of the dead plants, Zostera in particular, which forms thicket in the bay (Table 4.5.3).

Table 4.5.3 Relative numbers of some physiological groups of the aerobic saprotrophic microorganisms in seawater from the Nyisky Bay in 1998 (%) Physiological groups of Station microorganisms 1 2 3 Heterotrophic 100 100 100 Proteolytic 1,3 13,95 8,82 Lipolytic 27,3 5,9 –* Amylolytic 0** 0 22,05 Cd-resistant 0 0 0 Pb- resistant 42,4 0,08 29,4 Co- resistant 1.5 0 0 Cu- resistant 10 0,4 32,35 Ni- resistant 14,5 0,057 15 Zn- resistant 1,8 0,03 0 Fe- resistant 17,9 0,05 94,1 *(–) - indefinite **(0) – absence of growth

Cd-resistant microorganisms were not found in the examined water samples of the bay. Co- resistant bacteria occurred only in one sample; their relative number was 1.5 %. Numbers of Pb-, Cu-, Ni-, Zn-, Fe-, Ba- resistant microorganisms ranged within 102 – 104 cell/ml; number fluctuations were significant and constituted from 0.057 to 14.5 %, for example, for Ni. The occurrence of a great number of metal-resistant forms may indicate the possible man-caused pollution, on one hand, and may be connected with the geochemical peculiarities of the region, where the bay is located, on the other hand. Thus, the higher content of iron-resistant microorganisms indicating a presence of this metal in the bay waters may be explained by the peat grounds containing a significant number of iron. In June-July 1999, a total of 8 water samples were collected from 8 stations. Numbers of the following microorganisms were determined in samples: saprophyte heterotrophic colony- forming bacteria growing on RPA, marine heterotrophic organisms developing under the different water salinity (habitat of Yoshimitsu-Kimura); sanitary-indicative bacteria (bacteria of the group of enteric bacillus (BGEB) and pathogenic enteric bacteria (PEB)) (habitat of Endo,

СахНИРО Отчет по договору Y-00571 122 Ploskirev); petroleum-oxidizing, phenol-resistant, and metal-resistant organisms. Numbers of heterotrophic microorganisms in the bay water samples varied from 102 to 104 cell/ml, marine saprotrophic microorganisms from 102 to 104 cell/ml (Table 4.5.4). The lower numbers were timed to the stations in the southern part of the bay, where sampling was conducted under the mean water temperature 6.8 ºС. In the central and northern parts of the bay, sampling was conducted under the mean water temperature 15 ºС. The increase in water temperature promoted the increase in microorganism numbers in these regions two orders of magnitude higher. Bacteria of the group of enteric bacillus (BGEB) occurred in 5 water samples; at individual stations they occurred sporadically (4, 2, 3 cell/ml), and in water at 2 stations their numbers were significant (22-25 cell/ml). Pathogenic bacteria were not found in water samples. Detection of sanitary-indicative microorganisms under the temperatures unfavorable for development of mesophyll microorganisms could testify a new incoming of organic matters of the anthropogenic origin.

Table 4.5.4 Numbers of heterotrophic and pathogenic colony-forming bacteria (cell/ml) from the Nyisky Bay waters in June-July 1999 Groups of microorganisms Region Marine Conditionally- Heterotrophic Pathogenic saprotrophic pathogenic South of the bay 102 102 4 0 102 102 2 0 Central and 104 103 3 0 northern parts of 104 103 0* 0 the bay 103 103 0 0 104 104 22 0 103 103 25 0 103 102 0 0 *(0) – absence of growth

Indices of petroleum hydrocarbon-oxydizing bacteria (102-103 cell/ml) in 5 water samples indicated the background content of petroleum hydrocarbons and insignificant excess of background at two stations (Table 4.5.5). The maximum number of bacteria from this group was recorded at a station located in the northern part of the bay (104 cell/ml); this proves a significant pollution according to criteria developed for the Far East seas (Dimitrieva, 1999 ).

Table 4.5.5 Contents of phenol-resistant and petroleum hydrocarbon-oxydizing bacteria in the Nyisky Bay in 1999 (cell/ml) Groups of Stations microorganisms 1 2 3 4 5 6 7 8 PHC-oxydizing -* - 103 103 102 104 103 102 Phenol-resistant 102 102 103 103 102. - 103 102 *(–) - indefinite

Unlike was the picture of phenol pollution. A great number of phenol-resistant microorganisms was revealed in water samples from all the bay stations; this indicated a significant content of phenol compounds in the bay waters. Indices of abundance of this microorganism group varied by stations from 102 to 104 cell/ml. A previous chemical analysis of ground samples at the same bay stations revealed a background content of phenols. A microbe indication carried out in 1998 revealed the high number of this group of bacteria too. СахНИРО Отчет по договору Y-00571 123 Phenol compounds are related to the most prevalent pollutants coming to water bodies, as a rule, caused by the man’s economic activity. However, a great diversity of phenol compounds is formed in natural conditions during the process of hydrobiont vital activity (Saralov, 1979), under microbiological destruction and transformation of allochthonous and autochthonous organic compounds (Sirenko, Kozitskaya,1988), occurring both in water column and bottom sediments. Phenol concentrations in water ecosystems vary by seasons and differ by their contents in surface and near-bottom water layers. There are local zones with a high content of phenol compounds. Bottom sediments and sites of water bodies with intensive development of algae and macrophytes are related to them. In the Nyisky Bay they are the sites with Zostera thicket. Phenol compounds differ by their chemical inertness and resistance to microbiological decomposition. That is why, one of them are rapidly metabolized or oxidized be microbe community in water habitat, other remain unchangeable for a long time or accumulate in water bodies, constituting a menace for the water inhabitants. It is especially difficult to determine the origin (anthropogenic or natural) of phenol compounds, because they can come to the water systems from the outside (primary contamination) or accumulate in water bodies as a result of functioning all the links of a trophic chain (secondary contamination). Qualitative and quantitative contents of phenol compounds in natural waters are determined by the balance between purification and secondary contamination (Kondratyeva, 2000). High concentrations of phenol compounds, not connected with sewage discharge, can be found in water under releasing low-molecular aromatic compounds during destruction of the plant lignin-containing substrates, pesticides, polyaromatic cyclic compounds, heavy fractions of petroleum hydrocarbons accumulated in bottom sediments. A high number of phenol-resistant microorganisms can be explained by the above factors. By the literary data, zinc and copper concentrations increase in zones with the anthropogenic impact both in the habitat and organisms-inhabitants (Malinovskaya, Khristoforova, 1997). This, probably, explains the excess of the background content of copper at the Nyisky Bay stations, because during ten years this bay was a zone of a man’s economic activity. The higher percentage of Fe-resistant microorganisms at individual stations is connected with the geochemical peculiarities of the study region with the domination of peat strata containing a significant number of iron. Numbers of nickel- and lead-resistant bacteria being the markers of geochemical background were significant in individual water samples; their concentrations are always higher in the oil-gas regions. The higher percentage of all the examined metal-resistant forms (Table 4.5.6) was recorded at a station, where a hydrologic regime was characterized by the stagnation of water masses (proved by the type of ground – detritus) and, consequently, by the possible accumulation of metals in bottom sediments and their further incoming to the water column.

Table 4.5.6 Relative numbers of groups of metal-resistant bacteria in water samples of the Nyisky Bay in 1999 (% to the total number of heterotrophic microorganisms) Group of Station microorganisms 1 2 3 4 5 6 7 8 Cu 54.4 65.21 4.25 22.3 15.38 63.27 0* 18.5 Fe 54.4 -** 10.27 28.5 23.0 88.69 - 46.3 Ni 27.2 - 6.5 17.3 73.85 72.3 - 30.8 Pb - 86.95 6.75 28.8 47.7 77.0 - 46.3 Zn 6 21.73 2.36 5.77 5.38 50.8 8.8 74.0 *(0) – absence of growth **(–) - indefinite

СахНИРО Отчет по договору Y-00571 124 When studying a structure of the water microbe cenosis in the Nyisky Bay in July 2000, a total of 5 water samples and 4 ground samples were collected. Numbers of the following physiological groups of aerobic heterotrophic colony-forming microorganisms were determined in them: • saprophyte heterotrophic colony-forming bacteria growing on RPA; • marine heterotrophic organisms developing under the different water salinity (habitat of Yoshimitsu-Kimura); • sanitary-indicative bacteria (bacteria of the group of enteric bacillus (BGEB) and pathogenic enteric bacteria (PEB)) (habitat of Endo, Ploskirev); • petroleum-oxidizing, phenol-resistant, and metal-resistant organisms; destructors of biopolymers – amylolytic and proteolytic bacteria.

Indices of abundance in water samples for saprophyte heterotrophic forming colonies on RPA and marine heterotrophic organisms developing under the different water salinity were the same all over the bay and constituted hundreds cells per 1 ml. None of water samples contained sanitary-indicative microflora (Table 4.5.7).

Table 4.5.7 Numbers of heterotrophic aerobic colony-forming microorganisms in water samples from the Nyisky Bay in 2000, cell/ml Groups of microorganisms Sampling stations 1 2 3 4 5 Saprophyte heterotrophic 102 102 102 102 102 Marine heterotrophic 102 102 10 102 102 BGEB 0* 0 -** 0 0 Pathogenic enteric bacteria 0 0 - 0 0 Petroleum distructors 102 102 102 0 102 Phenol-resistant 102 102 10 0 102. *(0) – absance of growth **(–) - indefinite

Numbers of phenol-resistant, petroleum-oxidizing microorganisms coincided with those of saprophytes and marine heterotrophic microorganisms, that is, constituted hundreds cells in 1 ml. Results of determination of the amylolytic and proteolytic part of microflora were as follows: amylolytic microorganisms were practically absent in water samples. They were found only in one water sample constituting several tens cells per 1 ml. This may be explained by the high concentration of matters evolved by marine macrophytes, which are substrates for the amylolytic bacteria development. Proteolytic microorganisms were absent in samples at two stations. In the rest samples they constituted from 2.5 to 86.9 % of the total number of colony- forming heterotrophic microorganisms (Table 4.5.8). By the content of heavy metals, 2 water samples at stations located in the southeastern part of the bay and at the outlet of the bay were the purest. There Cd-resistant microorganisms were not found, and a percentage of the rest metal-resistant forms was lower compared to other stations. Indices of abundance for Fe-, Pb-, Cu-, Ni-resistant microorganisms were high (Table 4.5.8).

СахНИРО Отчет по договору Y-00571 125 Table 4.5.8 Relative numbers of heterotrophic aerobic colony-forming microorganisms in water samples from the Nyisky Bay in 2000, (% of the total number of heterotrophic microorganisms) Groups of Sampling stations microorganisms 1 2 3 4 5 Marine heterotrophic 100 100 100 100 100 Proteolytic 2.5 28.6 0 0 86.9 Amylolytic 2.5 0 - 0 0 Zn- resistant 26.3 40.8 10.0 0 33.30 Fe- resistant 67.5 58.0 10.0 32.2 92.7 Cu- resistant 40.0 62.0 10.0 0 98.6 Ni- resistant 82.5 64.0 20.0 6.45 52.2 Cd- resistant 10.0 20.0 0 0 20.28 Pb- resistant 51.2 72.0 6.67 12.9 72.4

A number of heterotrophic microorganisms in ground samples of the Nyisky Bay was several orders of magnitude higher. Indices of abundance for saprophyte heterotrophic microorganisms constituted 100 thousand cell/ml. Numbers of marine heterotrophic microorganisms were analogous: from several thousands to hundreds cells per 1 ml. A number of phenol-resistant microorganisms was determined only in one sample, which constituted thousands cells per 1 ml (Table 4.5.9).

Table 4.5.9 Numbers of heterotrophic aerobic colony-forming microorganisms in ground samples from the Nyisky Bay in 20000, cell/ml Groups of microorganisms Sampling stations 1 2 3 4 Saprophyte heterotrophic 103 105 104 104 Marine heterotrophic 105 104 103 105 Petroleum destructors - - 0 - Phenol-resistant 0 103 0 -

Indices of abundance for metal-resistant forms are similar to those for the water samples of the bay. Thus, among the metal-resistant microorganisms, cadmium-resistant microorganisms constituted the lowest percentage. The maximum indices of the relative abundance were made up by iron-, nickel-, and copper-resistant forms (Table 4.5.10).

Table 4.5.10 Relative numbers of heterotrophic aerobic colony-forming microorganisms in ground samples from the Nyisky Bay in 20000, (% of the total number of heterotrophic microorganisms) Groups of Sampling stations microorganisms 1 2 3 4 Zn- resistant 8.3 35.5 60.0 40.6 Fe- resistant 32.9 56.9 60.0 33.3 Cu- resistant 60.2 36.6 20.0 20.0 Ni- resistant 55.6 33.3 0 30.3 Cd- resistant 3.7 0.43 0 0.2 Pb- resistant 55.6 11.8 40.0 6.6

СахНИРО Отчет по договору Y-00571 126 4.6. Phytoplankton of the Nyisky Bay

4.6.1. Description of phytoplankton by the archive and literary data In August 1996 and September 1997, during studying the bays of the northeastern Sakhalin shelf, more than 200 microalgal species were found at 5 stations of the Nyisky Bay surface layer. Seven divisions formed the community; of them, diatoms were represented by the maximum number of species (55 – 94 % of the total number of species). Phytoplankton was the most diverse in the mouth of Tym River (47 species), near the central part of the spit (54 species), and closer to the outlet of the bay to the sea (104 species). Anabaena Scheremetievii, Eutreptia globulifera, Rhizosolenia setigera, Thalassionema nitzschioides, Fragilaria oceanica, Melosira moniliformis, Gomphonema lanceolatum, and Thalassiosira nordenskioeldii were the most frequent. Microalgae were the most abundant in the mouth of Tym River and near the outlet of the bay to the sea. The mean abundance of phytoplankton in 1996 was 52,576 million cell/l, mean biomass 24,247 g/m3, and in 1997 – 749 thousand cell/l and 915 mg/m3, respectively. Bluegreen Hapalosiphon sp., Anabaena Scheremetievii, Anabaenopsis sp. and euglenic Eutreptia globulifera algae dominated in the southern part of the area by numbers; in northern part – diatoms Rhizosolenia setigera, Thalassionema nitzschioides, Fragilaria oceanica, Melosira moniliformis. By the results of studies in the bay, a mass development of bluegreen, green, and diatom microalgae were observed in late August – early September. The maximum numbers of bluegreen and green algae were found in the southern part of the bay caused by the greatest water pollution in the mouth of Tym River. In the northern part of the area a mass development of diatom algae was noted (Kolganova, Mogilnikova, 1999). By the materials of SakhNIRO and ECS joint expedition in June-July 1999, more than 180 species and intraspecific taxons of microalgae were found. The mean abundance in the bay during this period was 537,44 thousand cell/l, mean biomass 611,75 mg/m3. Waters adjoining the outlets of the bay to the sea (a stronger affect of tidal waters) were characterized by the greatest biomass. Diatom algae played the main part in the biomass formation; cryptophyte, dinoflagellate, and euglenic algae were dominants at some sites. A development of algae common for polluted and eutrophic, or causing the water “blooming”: Cylindrotheca closterium, Sceletonema costatum, Eutreptia globulifera, Cryptomonas erosa was observed in the bay waters. Almost at all stations of the northern part a development of euglenic Eutreptia globulifera and cryptophyte Cryptomonas erosa algae, diatom Cylindrotheca closterium in the northern and southern parts, and diatom Sceletonema costatum in the middle part was observed. A spatial distribution of species-indicators of trophycity and pollution of environment coincided with the sites of the higher levels of contents of the biogenic and organic pollutants (PHC in water; PHC, pesticides and metals in bottom sediments) (Mogilnikova et al., 2001).

4.6.2. Characteristic of phytoplankton in 2002 In September 2002, a total of 173 species and intraspecific taxons of microalgae belonging to 7 divisions: diatoms Bacillariophyta (142 species and intraspecific taxons), dinoflagellates Dinophyta – 8, cryptophytes Cryptophyta – 7, green Chlorophyta – 6, bluegreen Cyanophyta, – 4, chrysophytes Chrysophyta and euglenic Euglenophyta – by 3 species were found on the area of Nyisky Bay (Appendix 2.6.1). Of diatoms, genera Navicula - 28, Nitzschia - 16, Thalassiosira - 8, Fragilaria – 7 species were the richest by species. Synedra tabulata (Ag.) Kutz. (100 % of frequency), Cocconeis scutellum Ehr. (93,8 %), Pleurosigma angulatum (Queck.) W.Sm. (93,8 %), and Thalassiosira sp. (93,8 %) were the most frequent.

СахНИРО Отчет по договору Y-00571 127 Species numbers at stations varied within 25-52. The main contribution into species diversity was made by diatom algae. The minimum number of species was recorded at the most shallow station of the bay (st. 4), maximum in its northern Dagi part. Ecological characteristic was determined for 24 species and intraspecific taxons (Appendix 2.6.1). Neritic species prevailed on the shelf area (79 % of the total number of species with the known ecological characteristic), proportions of pantalass and oceanic species were 17 and 4 %, respectively. A phytogeographic analysis was carried out for 31 species and intraspecific taxons with the known ecological belonging (Appendix 2.6.1). A total of 10 groups of species with the similar type of areas were found in the study region; of them, widely distributed species: cosmopolites (26 %), boreal (26 %), and tropical-boreal species (13 %) prevailed. A species composition was formed by freshwater (35 %), freshwater-brackish (28 %), and marine species (15 %). A spatial distribution of the total abundance and biomass was uneven (Appendix 2.6.2). The maximum estimates of quantitative characteristics were recorded in the northern part of the bay at station 1 (cell density 2,187 million cell/l, biomass 2,11 g/m3). A mass development of euglenic algae Eutreptia globulifera Van Goor., being an indicator of polluted waters, was observed there; their cell density reached 1,809 million cell/l (83 % of the total abundance), biomass 1,999 g/m3 (95 % of the total biomass).At all the rest stations the abundance and biomass estimates were low and varied within 6,123-193,956 thousand cell/l, 10,45-363,95 mg/m3, respectively. Analysis of the phytoplankton vertical distribution (for 4 deeper stations) has shown that at stations 7 and 8 (near Anuchin Strait) its cells were concentrated in the near-bottom layer, and at stations 4 and 12 in the surface layer. Abundance was formed by diatoms (49-91 % of the total abundance) and cryptophytes (20-45 %), and biomass only by diatoms (49-97 % of the total biomass). Diatom algae (49-91 % of the total abundance, 56-98 % of the total biomass) prevailed by the quantitative indices among divisions. Along with them, cryptophytes dominated by abundance (20-45 % of the total abundance). The exceptions were station 1 with euglenic dominants (83 % of the total abundance, 95 % of the total biomass) and station 11, where besides the diatoms, the dominants by abundance were bluegreen algae (31 %). In the study region, several diatom species dominated by abundance: brackish-marine Cocconeis scutellum Ehr. (25-27 % of the total abundance), marine Thalassiosira pacifica Gran et Angst (23-25 %); cryptophytes Plagioselmis punctata Butch. (to 31 %), Cryptomonas sp (to 24 %) and bluegreen Merismopedia tenuissima Lemm. (to 31 %) prevailed at single stations. Diatom algae: marine Thalassiosira pacifica Gran et Angst (20-28 % of the total biomass), marine Thalassiosira punctigera (Castr.) Hasle (27-29 %), and brackish-marine Pleurosigma angulatum (Queck.) W.Sm. (28-65 %) dominated by biomass. Thus, species of the neritic complex formed the base of phytoplankton in the bay. A total of 10 groups of species with a similar type of areas were found; of them, cosmopolites and boreal species prevailed. A species composition was almost equally formed by freshwater and freshwater-brackish species. The maximum estimates of quantitative characteristics were recorded at station 1, where a mass development of Eutreptia globulifera was observed. The mean estimate (except for station 1) of biomass was 125,24 mg/m3, abundance 72,306 thousand cell/l. Diatom and at some stations cryptophyte algae made the main conrtibution to the formation of abundance. Diatoms dominated by biomass all over the area, excluding the above station 1. Several species-dominants: by abundance - Cocconeis scutellum, Thalassiosira pacifica, Plagioselmis punctata; by biomass - Thalassiosira pacifica, Thalassiosira punctigera and Pleurosigma angulatum were found in the study region.

СахНИРО Отчет по договору Y-00571 128 4.7. Zooplankton of the Nyisky Bay

4.7.1. Description of zooplankton by the archive and literary data Zooplankton of the Nyisky Bay is the most studied among lagoons of the northeastern Sakhalin. A brief review of the main results of plankton surveys carried out by DVGU and SakhNIRO in summer 1996 is given below. A plankton community of the bay greatly depends upon the water hydrochemical composition and hydrologic regime. Due to the constant inflow of fresh water from the Tym River, the adjoining sites are strongly freshened, and during the ebb a line of fresh water occupies rather vast spaces. That is why, freshwater and brackish representatives of zooplankton are the most abundant. During the tide, marine forms, forming the major part of the bay biomass, entered the bay. The maximum biomass estimates were recorded in the region of Cape Medvezhiy, and near the Bauri Bay and Cape Shidlovsky, where the higher number of plankton was observed practically always. At the beginning of studies the biomass varied within 10-125 mg/m3, and in August-September from 140 to 688 mg/m3. Biomass in the bay is maintained at the rather high level due to incoming such neritic marine species as Pseudocalanus minutus3, Acartia clausi4, A. longiremis, Oithona similis, medusa and ctenophore, larval polychaetes and others with seawater during tides, and also due to spawning the representatives of the “lagoon” complex enduring а rather heavy freshening (Acartia, Eurytemora and nauplii of copepods). The base of net sampling was formed by copepods of 0.5 to 1.5 mm in size, which had a short period of development and that was why were found as adult specimens and so their larvae at different stages of maturity. Genera Аcartia (Acartia clausi, A. longiremis), Eurytemora (Eurytemora herdmani, E. asimmetrica), sub-order Harpacticoida (genera Harpacticus, Tisbe, Microsetella, Zaus, Scutellidium) were the most mass of them. The lowest abundance of Аcartia was recorded in mid-June (1-30 ind./m3), the highest abundance – by the end of July (to 5 thousand ind./m3 in the region of Anuchin Strait, in northeastern and central parts of the bay. A number of copepodid stages of Аcartia reached 71 % of their total abundance. Eurytemora frequency increased to 92 % from June to September, mainly, in the near-bottom horizon. In 1996, their maximum number was captured in the near-bottom horizon and constituted from 600 to 5800 ind./m3. The main places of Harpacticus aggregations were timed to the shallow sites of Cape Medvezhiy and north of the settlement Nyivo. Pseudocalanus minutus was recorded at the outlet of the bay; in July copepods from the genus Sinocalanus represented, mainly, by immature specimens occurred in catches sporadically. In addition to copepods, hydroid medusae, larval cirripedes, polychaetes, gastropods, bivalves, cladoceres, ostracods, and also cumaceans, gammarides, and larval fish occurred in samples (Velikanov et al., 1997). In 1999, during a joint expedition of SakhNIRO and ECS, a total of 40 forms of organisms from 18 groups were found in samples. Of 40 forms, 19 were facultative-planktonic, that is, related to nektobenthos (mysids, gammarides, cumaceans) and planktobenthos (majority of harpacticides, hydracarines, ostracods). Major species were related to brackish and euryhaline (Schmackeria inopina, Sinocalanus tenellus, Tachidius discipes, Harpacticus uniremis). Freshwater species enduring salinity (Eurytemora affinis) occurred at the most freshened sites, and at the saliner sites – marine coastal species enduring freshening (Acartia hudsonica, Pseudocalanus newmani, Podon leuckarti). The order Copepoda, which was represented in the bay by two suborders Calanoida (common plankters) and Harpacticoida (planktobenthos) was the richest by species. The latter were represented by genera Harpacticus, Tachidius, Tisbe and some other, which identification appeared to be impossible due to the absence of necessary keys. Females of major copepods had spermatophores or egg sacs. At the same time a number of nauplii was not high, that allowed to state the very beginning of mass spawning.

3 At present this species is redetermined as Pseudocalanus newmani. 4 At present this species is redetermined as Acartia hudsonica. СахНИРО Отчет по договору Y-00571 129 Two groups of zooplankters were clearly distinguished by the Shoener’s index. The complex with ostracodes from the family Cyteridae (indet.) being dominant and Lamprops korroensis includes, mainly, nektobenthic and planktobenthic organisms and occurs at shallow, strongly freshened sites. The mean biomass of this community was 457 mg/m3, mean abundance 2757 ind./m3. The dominants were relatively large ostracods from the family Cyteridae and L. korroensis, reaching, in total, 87,3 % of the total community biomass. Only the representatives of genera Eurytemora and Schmackeria inopina, which biomass did not exceed 4 % of the community biomass could be related to euplankton organisms of this group. Thus, facultative plankton (nektobenthos and planktobenthos) made up the base of community. The next group Eurytemora spp. juv. – E. asymmetrica occurs at a rather stable (regarding to salinity) site of the bay corresponding to the fairway and mouth of Dagi River during the tide, appearing to be sharply salined in this time. The mean biomass of this community was 493 mg/m3, mean abundance 35313 ind./m3. The base of this community was formed by the representatives of the genus Eurytemora (E. asymmetrica and its juveniles with some juveniles of the other eurytemores) constituting, in total, 64,1 % of the community biomass. The representatives of the genera Tachidius, Acartia, Balanus,and Podon significantly affected the biomass too. Ostracoda and Lamprops had not a significant influence on biomass formation, making up 2,7 % and less than 0,1 % of the community biomass, respectively. In general, one can note a significantly lower part of facultative-planktonic organisms compared to the above community. Their proportion constituted 14,1 % of the total biomass. Communities’ description shows that zooplankton of the Nyisky Bay consists, mainly, of “lagoon” forms common for brackish waters of different levels of mineralization, that is, enduring a rather strong change in hydrochemical and hydrologic conditions (Latkovskaya et al., 2001). In 1999, by the data of ECS, a total of 39 species of organisms belonging to 15 conventional groups were found in the Nyisky Bay during zooplankton surveys. Copepods prevailed in species composition; they constituted 50 % of species. The representatives of this zooplankton group were found at all stations during survey, except for a station located in the mouth of Tym River. Other groups of plankton organisms were represented not more than 1-2 species and forms. The maximum zooplankton biomass (5167 mg/m3) was recorded at station 43 in Dagi Bay in the region of Kaurunani Island. Such a high value was connected with the mysid Neomysis mirabilis and Neomysis awatschensis occurrence in sample. The minimum zooplankton biomass in the Nyisky Bay constituted 3.5 mg/m3 in the mouth of Tym River. The mean biomass was 309 mg/m3. In the Dagi lagoon, the highest estimates of zooplankton biomass varying from 20.5 mg/m3 in the region of channel between the bays Nyisky and Chaivo to 5167 mg/m3 in the open part of the area were recorded during the survey. The mean estimate of zooplankton biomass in the Dagi lagoon was 540 mg/m3. In the Nyivo lagoon the estimates of zooplankton biomass were significantly lower varying from 3.5 mg/m3 in the mouth of Tym River to 109 mg/m3 in the region of Cape Drizhenko. The mean biomass of the animal plankton constituted 39.7 mg/m3 for the Nyivo lagoon. The base of biomass at stations of the Dagi lagoon was formed by juvenile copepods from the genus Eurytemora, and also benthos organisms: ostracods, mysids, cumaceans. In the Nyivo lagoon, copepods Acartia clausi и Tachidius discipes prevailed by biomass among planktonic organisms. The mean number of plankton organisms in the Nyisky Bay was 12454 ind./m3. The maximum zooplankton abundance (61073 ind./m3) was recorded at a station in the channel near Gafovich Island, minimum (5 ind./m3) in the mouth of Tym River. Peculiarities of the area

СахНИРО Отчет по договору Y-00571 130 distribution, revealed earlier for biomass, remained for the numbers of planktonic animals. The highest mean density of planktonic organisms was recorded in the Dagi lagoon (22162 ind./m3) varying within 95-61073 ind./m3. The mean density of zooplankton in Nyivo lagoon was 1127 ind./m3 varying within 5-2580 ind./m3. In the quantitative respect, juvenile copepods from the genus Eurytemora prevailed in samples of the Dagi lagoon, and adult and juvenile copepod Tachidius discipes prevailed in the Nyivo lagoon. For both parts of the Nyisky Bay (Nyivo and Dagi lagoons), an evident tendency of increase in species diversity and quantitative indices of zooplankton when approaching to the near-strait parts of the lagoons has been watched in the area distribution of planktonic organisms. The mean estimate of zooplankton biomass at the daily station near the spit coast in the region of Nyivo settlement was 20.5 mg/m3, abundance 1179 ind./m3. Despite the revealed daily variation of zooplankton characteristics, a relationship of quantitative indices of zooplankton community with the tide phases was not found (Ecological studies…, 2001).

4.7.2. Characteristic of zooplankton in 2002 Zooplankton was unevenly distributed over the Nyisky Bay area. This is connected with some factors: a level of mineralization and water temperature, affect of river, brook and tide run- off, uneven bottom relief, vegetation development. Three communities form the bay zooplankton (Fig. 4.7.1). A total of 12 forms of organisms belonging to 4 groups were found in samples (Table 4.7.1); of them, copepods were the most diverse (9 forms). High numbers of the near-bottom forms were recorded in samples due to the relatively small depth of the bay. Table 4.7.1 A list of organisms found in the Nyisky Bay in 2002 № Group Form 1 Coelenterata Obelia longissima 2 Tunicata Fritilaria borealis 3 Sinocalanus tenellus 4 Neocalanus plumchrus 5 Pseudocalanus newmani 6 Eurytemora herdmani 7 Copepoda Acartia longiremis 8 Acartia clausi 9 Oithona similis 10 Harpacticoidae indet. 11 Nauplii copepoda 12 Mollusca Bivalvia, larvae

СахНИРО Отчет по договору Y-00571 131

Fig. 4.7.1. Distribution of zooplankton complexes in the Nyisky Bay in 2002

СахНИРО Отчет по договору Y-00571 132 Major species were related to brackish and euryhaline. Numbers of zooplankters (Table 4.7.2) in the bay varied within 575,0 to 80952,8 ind./m3, biomass 4,88 до 1899,64 mg/m3, averaged 212,13 mg/m3. The third community constituted the biomass maximum. Eurytemora herdmani made up the greatest biomass, and nauplii Eurytemora and other copepod species made up the greatest abundance.

Table 4.7.2 Zooplankton abundance and biomass by stations № st. Ny1 Ny2 Ny3 Ny4 Ny5 Ny6 Ny7 Ny8 Ny9 Ny10 Ny11 Ny12 N, 23400,0 4900,0 1900,0 80952,9 2200,0 1750,0 8776,4 14048,9 1025,0 575,0 2225,0 786,0 ind./m3 B, 119,30 65,75 26,45 1899,64 40,68 72,33 150,60 123,80 8,43 4,88 17,93 15,85 mg/m3

4.8. Benthos of the Nyisky Bay

4.8.1. General characteristics of benthos Benthos surveys in the Nyisky Bay were carried out by the complex expedition of SakhNIRO and ECS in July 1999 (Latkovskaya et al., 2001). The data of 54 dredged stations were described. Sampling was being conducted with the help of Petersen's grab (0.025 m2) or Levanidov's benthometer (0.16 m2). A total of 6 algal and higher plant species were found in the Nyisky Bay in July 1999 (Appendix 4.8.1). Mass forms of macrophytobenthos were represented by green algae Chaetomorpha linum (Müll.) Kütz, Enteromorpha sp. and flowering plants: grass-wrack Zostera marina L. and Z. japonica Aschers. et Graebn., pondweed Potamogeton pectinatus L. and P. perfoliatus L. A distribution of the total phytobenthos biomass had a spotted character varying from 0.3 to 1387.0 g/m2, averaged 84.7 g/m2 (Fig. 4.8.1). The base of phytobenthos biomass was formed by Z. marina. This species was distributed in the southern part of the Nyivo lagoon, at a site adjoining to the lagoon Anuchin Strait with salinity fluctuations from 7 to 30 ‰, at the depth of 0.3-4.5 m on silty-sand grounds; its biomass was from 0.3 to 1386.6 g/m2. Stations with the maximum estimates of phytobenthos biomass were recorded in the northern and southern parts of the lagoon. In the Dagi lagoon a phytobenthos biomass at stations with silty-sand grounds and 0.2- 1.1 m depth reached 120.0-997.2 g/m2. Zostera (Z. japonica) with 0.2-414.3 g/m2 biomass was recorded in the Dagi lagoon upper the Tomi River at depths of 0.3-0.9 m, and at 3 stations in the southern part of Nyivo lagoon on sandy-silt grounds, where its biomass did not exceed 2 g/m2. Two species of pondweed occurred separately in the very northern part of the Dagi lagoon. A pondweed P. perfoliatus with 0.5-49.9 g/m2 biomass was recorded at stations 48, 51, and 52 at 0.3-0.9 m depth on silty-sand grounds. Another species of pondweeds was found at stations 49, 50, and 55 at 0.6-0.7 m depth on silty- sand grounds. Green algae Enteromorpha sp. occurred sporadically with a small biomass in the southern part of the lagoon on sandy grounds. C. linum with the mean biomass of 0,15 g/m2 was recorded at stations 9, 12, and 41 on silty-sand grounds. During studies, a total of 93 macrozoobenthos representatives were found in the Nyisky Bay (Table 4.8.1). Polychaeta (25 species), larval Chironomidae (17), Oligochaeta (14), and Amphipoda (13) prevailed by the number of species. Bivalves and gastropods presented by 5 species. Other groups of invertebrates were represented by 1-3 species. Bivalves were the dominants in biomass forming in the Nyisky Bay (Fig. 4.8.2). They constituted more than 77 %

СахНИРО Отчет по договору Y-00571 133 of the total macrozoobenthos biomass. In general over the bay, the macrozoobenthos biomass varied from 0,1 g/m2 in the southern part to 611.0 g/m2 in the narrow central part joining lagoons Dagi and Nyivo (Fig. 4.8.3). The mean biomass was 31.1 g/m2. A density of macrozoobenthos colonies varied from 28 to 7953 ind./m2, averaged 1393 ind./m2. Stations, where zoobenthos biomass exceeded 100 g/m2, were located in the southern and central parts of the bay at 0.3-5.0 m depth on silty grounds. These sites were timed to a zone of confusion of the freshwaters flowing with the river run-off and being enriched with biogenic elements, and sea tidal waters. In the northern part of the Nyisky Bay the macrozoobenthos biomass was insignificant and constituted, on average, about 14 g/m2.

Table 4.8.1 Characteristics of abundance of the main macrozoobenthos groups in the Nyisky Bay Taxonomic groups Numbers of N, ind./m2 В, g/m2 species Polychaeta 25 184 1.1 Oligochaeta 14 - 1.1 Amphipoda 13 620 0.9 Chironomidae larvae 17 221 0.4 Bivalvia 5 44 24.3 Gastropoda 5 36 1.9 Isopoda 3 35 0.3 Others 11 253 1.2 Total 93 1393 31.1

A distribution of bivalve biomass (Fig. 4.8.2), in general, was similar to distribution of the total biomass of macrophyto- and zoobenthos (Fig. 4.8.1, 4.8.3), that proved a domination of this group in the bay. The base of Bivalvia biomass was formed by M. balthica. Its highest biomasses were recorded in the channel joining Dagi and Nyivo lagoons. Polychaetes in mass numbers inhabited silty and silty-sand grounds at 0.3–4.5 m depth. Maximum biomass estimates of (respectively, 11 and 28 g/m2) were recorded at depths of 2.2 and 4.2 m near the northern extremity of Gafovich Island. The main biomass of polychaetes (15.9 g/m2) was formed by representatives of the family Nereidae, and Spio filicornis (O.F.Müller) prevailed by density (2547 ind./m2). Biomass of oligochaetes, in general over the bay, did not exceed 6 g/m2, and its maximum estimate (10 g/m2) was recorded in the mouth of Bolshaya Veni River, where some accumulation of biogenic elements incoming to the bay with a river run-off took place; this is favorable for oligochaetes development. Larval aggregations of Chironomidae were timed to the most freshwater site of the Dagi lagoon, above the Larvo Island (mouth of the Tapauna River, and narrow, stretched from south to north, lagoon site along the sand spit). Larval chironomids were recorded at 7 stations, mainly on silty grounds at depths not exceeding 1.1 m.

СахНИРО Отчет по договору Y-00571 134

52.25 р. Эвай 1000

750

р. Тапауна о. Лярво 500

200

р. Томи 100

52.05 о. Гафовича 0

р. Баури

пр. Анучина зал. Баури

р. Мал. Вени

р. Бол. Вени

51.85

р. Тымь

р. Имчин 143.05 143.15 143.25

Fig. 4.8.1. Distribution of the total macrophytobenthos biomass (g/m2) in the Nyisky Bay in 1999 (according to Latkovskaya et al., 2001)

СахНИРО Отчет по договору Y-00571 135

300 52.25 р. Эвай

250

200 р. Тапауна о. Лярво 150

100

р. Томи 50

52.05 0 о. Гафовича

р. Баури

пр. Анучина зал. Баури 5

р. Мал. Вени

р. Бол. Вени

51.85

р. Тымь

р. Имчин

143.05 143.15 143.25

Fig. 4.8.2. Distribution of bivalve biomass (g/m2) in the Nyisky Bay in 1999 (according to Latkovskaya et al., 2001)

СахНИРО Отчет по договору Y-00571 136

300 52.25 р. Эвай

250

200 р. Тапауна о. Лярво 150

100

р. Томи 50

52.05 0 о. Гафовича

р. Баури

пр. Анучина зал. Баури

р. Мал. Вени

р. Бол. Вени

51.85

р. Тымь

р. Имчин 143.05 143.15 143.25

Fig. 4.8.3. Distribution of the total macrozoobenthos biomass (g/m2) in the Nyisky Bay in 1999 (according to Latkovskaya et al., 2001)

СахНИРО Отчет по договору Y-00571 137 4.8.2. Benthos communities By the results of the 1999 dredged survey, three isolated macrobenthos communities were distinguished in the Nyisky Bay (Fig. 4.8.4).

1 52.25 р. Эвай 2

3

р. Тапауна

Лагуна Даги

р. Томи

52.05 о. Гафовича

р. Баури

5 пр. Анучина зал. Баури

р. Мал. Вени

Лагуна Ныйво р. Бол. Вени

51.85

р. Тымь

р. Имчин

143.05 143.15 143.25

Fig. 4.8.4. Distribution of the main macrobenthos communities in the Nyisky Bay in 1999. Communities: 1- Zostera var.; 2- Macoma balthica; 3- Zostera marina (according to Latkovskaya et al., 2001).

СахНИРО Отчет по договору Y-00571 138 Community Zostera var. This community is distinguished on the area of Dagi lagoon in its codend part (stations 38, 45, 37, 35, 36, 47, 1). The community is timed to the shallow part with depths from 0.4 to 1.1 m on silty and silty-sand grounds. 31 representatives of macrobenthos enter the community composition (Table 4.8.2). Table 4.8.2 Quantitative characteristics of benthos in the community Zostera var. Biomass, Status Species Group N, ind./m2 В, g/m2 F ID % Dominant Zostera var. Magnoliophyta 400.880±56 89.6 100.08960.50 Total 1 400.880±26 89.6 8960.50 Macoma balthica Typical for I order Bivalvia 103.7±20.1 39.852±9.5 8.9 55.6 494.87 (Linne) Total 1 103.7±20.1 39.852±9.5 8.9 494.87 Cryptonatica Gastropoda 111.4±27 2.591±0.75 0.6 55.6 32.18 Typical for II janthostoma (Pall.) order Eogammarus tiushovi Amphipoda 41.6±4.6 1.206±0.11 0.3 77.8 20.97 (Derzhavin) Total 2 153.0±12.1 3.798±0.34 0.8 53.15 Photis sp. Amphipoda 218.1±69 0.459±0.14 0.1 33.3 3.42 Oligochaeta indet. Oligochaeta 143.4±39 0.268±0.06 0.1 44.4 2.67 Secondary for I Photis sp. 1 Amphipoda 29.6±5.6 0.280±0.071 0.1 33.3 2.09 order Liostomia sp. (?) Gastropoda 51.9±16 0.281±0.088 0.1 22.2 1.40 Hediste japonica Izuka Polychaeta 16.1±2.9 0.176±0.032 0.0 33.3 1.31 Total 5 459.1±32 1.464±0.083 0.3 10.88 Calliopius laeviusculus Amphipoda 24.8±4.9 0.129±0.025 0.0 33.3 0.96 Kroyer Spio sp. Polychaeta 29.6±9.9 0.326±0.11 0.1 11.1 0.81 Ischyrocerus sp. Amphipoda 69.6±22 0.148±0.046 0.0 22.2 0.73 Nereis pelagica Polychaeta 5.0±1.1 0.129±0.029 0.0 22.2 0.64 Saduria entomon Isopoda 6.3±1.5 0.055±0.012 0.0 33.3 0.41 (Linne) Corophium steinegeri Amphipoda 9.4±1.7 0.047±0.009 0.0 33.3 0.35 Gurjanova Capitellidae indet. Polychaeta 47.9±10.3 0.046±0.01 0.0 33.3 0.34 Archaeomysis Mysidae 6.9±1.6 0.068±0.015 0.0 22.2 0.34 grebnitzkii Czerniavsky Heteromastus filiformis Polychaeta 17.8±4.9 0.067±0.017 0.0 22.2 0.33 Spionidae indet. Polychaeta 17.8±4 0.056±0.017 0.0 22.2 0.28 Chironomidae larvae Insecta 34.7±11.6 0.087±0.029 0.0 11.1 0.22 Secondary for II indet. order Diastylis sp. Cumacea 13.2±3.9 0.035±0.011 0.0 22.2 0.18 Anisogammaridae indet.Amphipoda 8.1±2 0.021±0.0044 0.0 33.3 0.15 Crangon septemspinosa Decapoda 0.3±0.12 0.050±0.017 0.0 11.1 0.13 Say Lineidae indet. Nemertini 3.0±1 0.030±0.0099 0.0 11.1 0.07 Eteone longa Polychaeta 14.8±4.9 0.030±0.0099 0.0 11.1 0.07 Eogammarus kygi Amphipoda 1.0±0.35 0.021±0.0069 0.0 11.1 0.05 (Derzhavin) Eogammarus hirsutimanus (Kurenkov Amphipoda 0.3±0.12 0.014±0.0046 0.0 11.1 0.03 et Mednikov, 1959) Eogammarus sp. Amphipoda 1.4±0.46 0.014±0.0046 0.0 11.1 0.03 Corophiidae indet. Amphipoda 1.7±0.58 0.009±0.0029 0.0 11.1 0.02 Phyllodocidae indet. Polychaeta 7.4±2.5 0.007±0.0025 0.0 11.1 0.02 Phascolosoma sp. Sipuncula 1.5±0.49 0.003±0.001 0.0 11.1 0.01 Chone teres Polychaeta 0.3±0.12 0.002±0.0006 0.0 11.1 0.00 Total 23 323.1±21.1 1.392±0.09 0.3 6.18 Total by the 32 1038.9±60 447.385±28 100.0 9525.59 community СахНИРО Отчет по договору Y-00571 139

Larval chironomids were the richest by species in the community (9 species). Amphipods, polychaetes, and oligochaetes made up by 4 species. Grass-wracks (Z. japonica and Z. marina) formed the main biomass of the community (95,35 % of the total macrobenthos biomass). The mean biomass of the community was 183.11 g/m2. Amphipods Kamaka kuthae, Eogammarus tiuschovi and three species of larval chironomids played an important part in forming the total density. Z.marina was related to the typical species of I order; 5 species were noted as typical of II order: bivalve M. balthica, larval chironomid Glyptotendipes paripes, two species of oligochaetes, and amphipods E. tiuschovi and K. kuthae. A major part of macrobenthos representatives were related to the secondary species in the community with the mean biomass not exceeding 0.5 g/m2. Community Macoma balthica Stations 5, 21, 1(2), 53, 40, 15, 23, 6, 41,39, and 26 characterizing the community M. balthica in Zostera thicket are distinguished into the well isolated claster (Table 4.8.3). Table 4.8.3 Quantitative characteristics of benthos in the community Macoma balthica + Zostera var. Biomass, Status Species Group Ind./m2 G/m2 F ID % Macoma balthica (Linne) Bivalvia 809.6±135 562.674±215 50.1 100.05010.58 Dominant Zostera var. Magnoliophyta 382.593±213 34.1 66.7 2271.31 Total 2 809.6±135 945.267±105 84.2 7281.90 Mytilus trossulus Bivalvia 102.2±52 85.813±44 7.6 66.7 509.44 Typical for I order Algae indet. Algae 0.0 66.667±38 5.9 33.3 197.89 Total 2 102.2±52 152.480±14 13.6 707.33 Typical for II Liocyma fluctuosa (Gould, 1841) Bivalvia 26.7±12 14.222±5,2 1.3 66.7 84.43 order Crangon septemspinosa Say Decapoda 8.9±2,6 7.422±2,2 0.7 66.7 44.06 Total 2 35.6±3,6 21.644±2 1.9 128.50 Eogammarus tiushovi Amphipoda 22.2±9,3 0.800±0,27 0.1 66.7 4.75 (Derzhavin) Secondary for I Cryptonatica janthostoma (Pall.) Gastropoda 22.8±7 0.593±0,19 0.1 66.7 3.52 order Archaeomysis grebnitzkii Mysidae 17.8±6,8 0.356±0,1 0.0 66.7 2.11 Czerniavsky Saduria entomon (Linne) Isopoda 40.0±12 0.267±0,08 0.0 66.7 1.58 Total 4 102.8±8,8 2.015±0,16 0.2 11.96 Eteone longa Polychaeta 9.1±2,6 0.147±0,073 0.0 66.7 0.87 Corophiidae indet. Amphipoda 26.7±15 0.267±0,15 0.0 33.3 0.79 Oligochaeta indet. Oligochaeta 222.2±128 0.244±0,14 0.0 33.3 0.73 Echiuridae indet. Echiuridae 4.4±2,6 0.200±0,12 0.0 33.3 0.59 Calliopius laeviusculus Kroyer Amphipoda 22.2±13 0.138±0,08 0.0 33.3 0.41 Laonice cirrata Polychaeta 9.3±5,3 0.116±0,067 0.0 33.3 0.34 Terebellidae indet. Polychaeta 4.4±2,6 0.111±0,064 0.0 33.3 0.33 Secondary for II Photis sp. Amphipoda 22.2±13 0.067±0,038 0.0 33.3 0.20 order Capitellidae indet. Polychaeta 88.9±51 0.067±0,038 0.0 33.3 0.20 Glycinde armigera Moore, 1911Polychaeta 8.9±5,1 0.067±0,038 0.0 33.3 0.20 Scalibregma sp. Polychaeta 4.4±2,6 0.044±0,026 0.0 33.3 0.13 Ischyrocerus commensalis Amphipoda 13.3±7,7 0.040±0,023 0.0 33.3 0.12 Chevreux, 1900 Photis sp. 1 Amphipoda 13.3±7,7 0.040±0,023 0.0 33.3 0.12 Pontoporeia affinis Lindstrom Amphipoda 4.4±2,6 0.018±0,01 0.0 33.3 0.05 Total 14 453.9±49 1.565±0,13 0.1 5.08 Total by the 24 1504.1±1321122.971±118 100.0 8134.76 community

It was observed both in the northern and southern parts of the Nyisky Bay coinciding with the lagoon fairway and being limited by the distribution of brackish waters. This community was noted on fine sand, silty, and silty-sand grounds. It occurred from the river

СахНИРО Отчет по договору Y-00571 140 mouths to the straits at depths of 0.3 to 5 m. A total of 39 macrobenthos species entered the community composition; among them polychaetes and amphipods prevailed by species composition (10 and 6 species, respectively). Bivalves formed the main biomass of the community (67.2 % of the total macrozoobenthos biomass) including the dominating species with the mean biomass of 94.3 g/m2, under the mean abundance of 124 ind./m2. The mean total abundance of macrobenthos organisms was 912 ind./m2, under the total biomass of 145.97 g/m2. The important part in forming a total biomass was played by Z. marina, which together with Littorina sitkana Philippi made up a group of typical species of I order. Among the typical species of II order the following species were noted: bivalve Liocyma fluctuosa Gould, gastropod Fluviocingula sp., amphipod E. tiuschovi, and polychaete S. filicornis. A number of polychaete S. filicornis in the community varied from 3 to 2013 ind./m2, averaged 200 ind./m2. Community Zostera marina This community occupies the area adjoining to the lagoon Anuchin Strait, central part of the southern lagoon site, and mouths of rivers Malaya Veni and Bolshaya Veni (stations 16, 27, 3, 10, 4, 17, 11, 28, 9, 12, 14). The community is under the influence of sea tidal waters and timed to the fine sand, silty-sand, and silty grounds at depths not exceeding, as a rule, 1 m. A total of 40 macrobenthos representatives entered the community composition. By the composition of bottom inhabitants, this community was close to the community M. balthica. Phytobenthos, as in the Macoma community, was represented by two species of Zostera and green alga C. linum. Polychaetes (10 species) and amphipods (7 species) dominated by the number of species too. Oligochaetes were represented by 6 species, bivalves and gastropods by 4 and 3 species, respectively. However, marine Zostera formed the main biomass of this community; it constituted more than 90 % of the total macrobenthos biomass. The mean density of populations was 559 ind./m2, mean biomass 402.84 g/m2. Molluscs M. balthica, L. sitkana and gammarides E. tiuschovi belonging to the typical forms of this community made up the greatest density and biomass of the zoobenthos organisms.

4.9. Ichthyofauna of the Nyisky Bay

Complex surveys in this bay have been conducted by SakhNIRO in 1995, 1996 (Zverkova et al., 1997) and in 1999 (Latkovskaya et al., 2001). Both by the results of these surveys and literary data (Taranets, 1937б; Churikov, 1978; Gritzenko, 1990, 2002; Report …, 1957; Churikov, Karpenko, 1987; Ivshina, 1992; Safronov et al., 2003) a species composition of the bay ichthyofauna includes about 50 species of 20 families (Table 4.9.1).

Table 4.9.1 A list of fish and fish-like species of the Nyisky Bay Family Species and subspecies Petromyzontidae Lethenteron japonicum – arctic lamprey **Clupea pallasii – herring Clupeidae ****Sardinops sagax melanosticta – west Pacific sardine *Acipenser medirostris – Sakhalin sturgeon Acipenseridae *Huso dauricus – kaluga sturgeon Oncorhynchus gorbuscha – pink salmon Oncorhynchus keta – chum salmon Oncorhynchus masou – masu salmon Salmonidae Oncorhynchus kisutch – coho salmon ***Salvelinus leucomaenis – Sakhalin char *** Salvelinus malma krascheninnikovi – southern malma *Parahucho perryi – Sakhalin taimen Coregonidae Coregonus ussuriensis – Ussuri whitefish Osmeridae Mallotus villosus – capelin СахНИРО Отчет по договору Y-00571 141

Hypomesus japonicus – smelt Hypomesus nipponensis – wakasagi Hypomesus olidus – pond smelt Osmerus mordax – Asiatic smelt Esocidae Esox reichertii – Amur pike Salangidae Salangichthys microdon – icefish Carassius auratus gibelio – common wild goldfish Phoxinus perenurus – lake minnow Rodeus sericeus – Amur bitterling Cyprinidae Leuciscus waleckii – Amur ide ***Tribolodon brandtii – eastern redfin ***Tribolodon ezoe – Pacific redfin ***Tribolodon hakuensis – big-scaled redfin Cobitis lutheri – loach Cobitidae Misgurnus nikolsky – Nikolsky’s loach Balitoridae Barbatula toni – Siberian stone loach Gadidae **Eleginus gracilis – saffron cod Gasterosteus aculeatus – threespine stickleback Pungitius pungitius – ninespine stickleback Gasterosteidae Pungitius sinensis – Amur stickleback Pungitius tymensis – Sakhalin stickleback Opisthocentrus ocellatus – spottyfin gunnel Stihaeidae Pholidapus dybowskii – Dybowsky’s blenny Zoarcidae Zoarces elongates – Pacific eelpout Hexagrammos octogrammus – masked greenling Hexagrammidae Hexagrammos stelleri – whitespotted greenling Gobiidae Chaenogobius urotaenia Cottus amblistomopsis – Sakhalin sculpin Cottidae Megalocottus platycephalus – flathead sculpin Myoxocephalus jaok – plain sculpin Blepsiidae Blepsias cirrihosus – whiskered sculpin Limanda aspera – yellowfin sole Limanda punctatissima – longsnout flounder Pleuronectidae ***Platichthys stellatus – starry flounder Liopsetta pinnifasciata – banded flounder Pleuronectes quadrituberculatus – Alaska plaice *Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the last years

Ichthyofauna of the bay consists of the representatives of freshwater, anadromous, and marine fish species. Freshwater species (common wild goldfish, Amur bitterling and others) inhabit the more freshened sites of the bay. Anadromous fishes, which migrate far (arctic lamprey, Pacific salmon, and others) occur only in the definite year periods. They migrate to the river mouths through two straits joining the bay with the open part of the sea. Some species (Sakhalin taimen, Pacific redfins and others) occur in the bay during a long period of life, sometimes moving out of the bay to the open part of the sea. Marine fishes were observed both all over the bay area (euryhaline), or in the straits and adjoining parts. Juvenile starry flounder, abundant on the northeastern Sakhalin shelf, feed at the shallow sites of the bay. Mature specimens of this species penetrate into the bay along the fairways in summer-autumn through the straits. In the Nyisky Bay the processes of change of the ichthyofauna species composition and fish abundance and biomass during a year are identical to those taking place in the Piltun Bay. СахНИРО Отчет по договору Y-00571 142 In the summer-autumn period, Pacific salmon dominate both by numbers and biomass (Gritzenko, 1990, 2002). Pacific herring, chum and pink salmon for the base of the fishery in the bay. A specialized fishery of chum has been closed since 1993. At present, chum salmon are fished in the control regime, and by the aboriginals. Sakhalin char and Pacific redfins have a great abundance in this period too (Churikov, 1987; Gritzenko, 1990, 2002; Zverkova et al., 1997). In the winter period the base of ichthyocenosis by biomass is formed by flathead sculpin and saffron cod (Ivshina, 1992). Banded flounder, Pacific eelpout, smelts, herring and others are less abundant in catches. In December-January, flathead sculpin forms spawning aggregations (Volodin, 1992). A fishing of saffron cod and flathead sculpin is conducted in winter in the Nyisky Bay. Four patrimonial communities of nivkhs: «Veni», «Limanzo», «Venivongun», «Kongargobakhrsh» are located on the bay shore. In total, 28 persons live in these settlements. The Pacific salmon fishing by aboriginals is the most developed in the basin of this bay. This is connected with the fact that at present the main locality of aboriginals is the settlement Nogliki, which is located in the low part of Tym River flowing into the Nyisky Bay.

4.9.1. Main commercial species The bay basin includes one of the largest water courses of Sakhalin Island the Tym River. Of Pacific salmon, pink, chum, coho, and masu enter for spawning the rivers flowing into the Nyisky Bay. Pink (in odd years) and chum salmon are of commercial importance. Chum salmon is the main commercial species. The coho salmon abundance is significantly higher compared to other bays of northeastern Sakhalin. The main fishing of Pacific salmon historically has been conducted predominantly in this water body. A total area of salmon spawning grounds in rivers flowing into the Nyisky Bay makes up 2761,8 thousand m2 (Table 4.9.2). Chum spawning grounds constitute a significant part in the basin of Tym River (Report…, 1957).

Table 4.9.2 Rivers of the Nyisky Bay basin and their spawning areas Length, Spawning area, River Water area, km2 Species of Pacific salmon km m2 Tapauna 17 65,9 3420 pink Dagi 98 780 323000 pink, chum, coho Tomi 40 114 24040 pink Bauri 17 44 12900 pink Malye Veni 17 43 8000 pink Bolshiye Veni 46 198 20200 pink, chum, coho Dgimdan 68 312 53500 pink, chum, coho Tym 330 5850 2316770 pink, chum, coho

Pink salmon The average annual biomass of pink salmon in the Nyisky Bay is given as the mean annual run of a population expressed in tons. One should note that this value is very changeable. The following indices change by individual years: catch size, numbers of spawners entered the rivers for spawning, and mean individual weight of spawners (Table 4.9.3). Judging from the Table data, the mean pink salmon biomass in the Nyisky Bay in even years is very low and fluctuates from 59,4 to 61,9 tons. In odd years this index is significantly higher. On average, this value is 1862 tons (from 1022,0 to 2896,2 t).

СахНИРО Отчет по договору Y-00571 143 Table 4.9.3 Data on the pink salmon abundance, catch, and biomass in the Nyisky Bay Data Years 1995 1996 1997 1998 1999 2000 2001 2002 Numbers in Tym 589,6 24,0 267,2 38,0 128,5 - 1781,1 - River, thousand ind. Catch, t 611,0 30,0 1368,0 22,5 657,0 25,0 954,0 350,0 Mean weight, kg 1,33 1,18 1,36 1,06 1,36 1,22 1,18 1,26 Catch, thousand ind. 812,6 35,4 1860,5 23,9 893,5 30,5 1115,1 441,0 Annual biomass, t 1402,2 59,4 2127,7 61,9 1022,0 - 2896,2 - *- - no data

In Tym River, fry make early downstream migration to the sea (approximately two weeks earlier compared to other rivers flowing into the bay). This is explained by the relatively low abundance of the Tym River pink stock, and a high water-warming of the river causing a comparatively rapid development of embryos (Gritzenko, 1990, 2002). In odd years, 14,8 million pink fry, on average, run through the bay for the sea feeding. In even years – 74,9 million fry. The pink salmon fishing in the bay begins in July, and a peak occurs on I-II decades of August. In recent years a license fishing and that of aboriginal are realized since I decade of July through August (Gritzenko, 1990; 2002; own observations).

Chum salmon Single specimens of autumn chum salmon occur in the Nyisky Bay in the second half of July. By the mean long-term data, this species is the most abundant in September. Chum salmon begin to run to the Tym River spawning grounds (upper stm. Kirovskoye) in late July – early August. Its spawning run completes in different years since 30 October to 18 December. Terms of spawning are shifted approximately two weeks compared to the spawning run (Gritzenko et al., 1978; Gritzenko, 1990, 2002). At present, chum salmon stocks of the Tym River are in the depressive state after the fishery closure in 1993. During ten years of the closure the chum salmon abundance varied from 57 to 548 thousand ind., and only once its abundance reached the maximum index in 1999. It happened due to the returns of the high-abundant generation of 1996. The mean abundance of chum salmon for the ten-year closure of fishing constituted 196,5 thousand ind.; this is 2,2 times less than in the previous ten-year period (Kovtun, 2003). The length of chum salmon migrating to the Tym River varied from 65,3 to 75,5 cm, weight from 3,1 to 5,0, fecundity from 2650 to 3040 eggs (Gritzenko et al., 1978; Gritzenko, 1990, 2002). Fish at 3+ and 4+ age significantly prevailed by numbers (Table 4.9.4) (Kovtun, 2003). Table 4.9.4 Age composition of the Tym River chum salmon Age, % Year Numbers 2+ 3+ 4+ 5+ 1992 5,7 67,7 26,6 - 201 1993 3,0 64,8 32,2 - 298 1994 1,5 58,7 37,2 2,5 337 1998 3,3 63,9 32,4 0,4 490 1999 5,8 72,1 21,2 0,9 534 2000 1,8 57,2 39,4 1,6 500 2001 4,7 61,7 32,5 1,1 363 2002 3,8 43,4 51,4 1,4 500

СахНИРО Отчет по договору Y-00571 144 Nyisky Bay is the main region in northeastern Sakhalin of chum salmon fishing, which originate, mainly, in the Tym River. By the end of 1950s, chum salmon fishing was realized in the mouth of Dagi River. In the 1950s and early 1960s, it was fished by fixed nets and beach seines. Annually, 6-7 fixed nets were settled for fishing. Since 1963, only fixed nets had been used; their number reached 10 units by 1965. The maximum number of this gear (16) was in 1974. By 1980, the number of fixed nets was reduced to 7. Fishing began on I decade of September, and in some years it was shifted to III decade of September. The intensive fishing started since III decade of August through II decade of September (Gritzenko, 1990, 2002). Since 1993 till our days there is a closure for a specialized chum salmon fishing (Kovtun, 1995). The total volume of chum salmon capture from the bay consists of its use for fish culture, control catch, and aboriginal fishing (Table 4.9.5, 4.9.6). A control catch and aboriginal fishing are realized in the bay during II decade of August through September.

Table 4.9.5 Chum salmon capture in the Nyisky Bay Capture Used for fish culture Year tons thousand ind. tons thousand ind. 1993 73,2 17,9 83,1 21,5 1994 76,2 19,6 86,4 157+11 1995 106,9 27,4 202,8 28,6+24 1996 97,3 24,3 147,9 27,4+9,6 1997 90,4 27,4 120,2 22,7+13,7 1998 76,4 21,8 88,6 18,1+7,2 1999 57,4 16,7 116,6 22,8+11,1 2000 69,4 19,3 168,5 32,5+14,3 2001 96,6 26,9 155,3 31,6+11,5 2002 45,6 11,0 74,5 15,9+2,1

Table 4.9.6 Aboriginal chum salmon fishing in the Nyisky Bay Catch,t Year Nyisky Bay Tym River 1997 56,4 15,0 1998 51,4 17,0 1999 35,7 18,6 2000 18,4 15,3 2001 19,4 19,0 2002 9,1 10,0

Coho salmon During the chum salmon fishing, coho salmon practically always occurs in catches. Sometimes its proportion reached 30,0% (Kovtun, 1989; Shershnev et al., 1992). The main spawning grounds of coho salmon are located in the Tym River. At the same time, coho enters other rivers flowing into the bay. About 80,0-90,0 % of specimens spawn in Tym River during the period since the second half of October to the end of the second decade of November. Spawning is practically completed by the second half of December. As a rule, coho salmon is represented by two age groups (21+ and 32+) in the Nyisky Bay. In major cases, specimens at 32+ age prevailed. During several years, only the old age group occurred in the large spawning stock (Tym) among mature fish. Specimens occurring in the sea during a short time period and being matured in the year of downstream migration are met very rare (Gritzenko, 2002).

СахНИРО Отчет по договору Y-00571 145

Masu salmon This species is not abundant. Fry are common in rivers flowing into the bay. Masu salmon occur in the mouth of Tym River in mid-May; anadromous migration completes by early August. Females made up from 50,8 to 81,2 % among adult fish. Females also prevailed by numbers among the downstream migrants. The length of the Tym River adult fish varied from 40,0 to 71,0 cm, weight from 0,75 to 3,55 kg. As a rule, they were at 21+ and 32+ age. Elder specimens prevailed by numbers. Fry usually migrate downstream during July. Their age was 1+ and 2+; the latter dominated by numbers. Their lengths varied from 9,0 to 15,8 cm (Gritzenko, 2002). By the results of catches with the help of the control fixed net during 24 hours in Nyisky Bay, a percentage ratio between salmon species in late July – September can be presented (Table 4.9.7). In 2002 (even year) chum salmon formed the base of the total catch. Catches of other species were insignificant. In late July – August, pink salmon and Sakhalin char dominated in catches (Table 4.9.7). It is clear that a daily salmon catch in odd years during the similar time periods will be somewhat different. The base of catch will be formed by pink salmon, whose numbers have increased in recent years. For the rest species, a tendency of their daily catch, evidently, will remain. Fishing sites attached to the companies in Nyisky Bay are given in Table 4.9.8 (A list of fish commercial sites…, 1998).

Table 4.9.7 Daily salmon catch by the control fixed net in the Nyisky Bay in 2002 (Kovtun, 2003) Date of Salmon catches by species, kg catch chum coho pink char total 29,07 - - 110,0 - 110 15,08 330 200 - 50 530 16,08 120 - 50 - 170 17,08 280 - 20 - 300 20,08 730 - 70 150 950 26,08 780 260 100 100 1240 mean 448 230 70 100 3350 29,08 3290 - - - 3290 02,09 8000 10 - 260 8270 03,09 7300 500 - 100 7900 06,09 2000 - - - 2000 08,09 2600 - - - 2600 mean 4638 255 - - 24060 09,09 380 100 - - 480 14,09 580 - - - 580 16,09 80 10 - - 90 Всего 26470 1080 350 660 28560 Proportion, 92,7 3,8 1,2 2,3 %

СахНИРО Отчет по договору Y-00571 146 Table 4.9.8 Fish commercial sites used by companies in the Nyisky Bay № of site Boundaries Extension, km User Patrimonial 1 Cape Medvezhiy – B.Veni River 4 community “Venivongun” 2 Cape Takrvo – 3 km north of Cape Takrvo 3 DOZT «Lovets» 3 km north of Cape Takrvo – northern 3 8 Co-operative “Dagi” extremity of Gafovich Island Southern extremity of Getabu Island – Co-operative 4 22 Evai River «Priroda» Cape Medvezhiy – 2 km south of Cape Medvezhiy – Krotovsky Island – old bed Fish collective farm 5 7 of Tym River – 7 km south of Cape Age – «Vostok» Cape Tarkovo – B.Veni River Patrimonial Old bed of Tym River – 7 km south of 6 7 community Cape Age Kanchargobakhrsh» Zeleniy Island – 1 km south of Cape 7 6 Co-operative «Dagi» Medvezhiy

Pacific herring The terms of herring spawning in the Nyisky Bay are: II decade of May – II decade of June; mass spawning: last 5-day of May – II decade of June. The dates of approach of the spawning herring and their mass spawning depend on the temperature regime and ice condition in the bay and adjoining sea area. The most favorable seawater temperature at the beginning of herring spawning is 2,5-3,0 °С (Frolov, 1965). Herring spawn in the vast shallow zones remote from the mouths of large rivers; marine grass Zostera marina serves as a substrate for their eggs. Some herring move for spawning to the northern part of the Nyisky Bay: Dagi lagoon. There, the vast spawning grounds are noted too, especially in the very northern part of the bay. By the visual survey of spawning grounds in the Dagi lagoon, the egg density on the substrate is compared with the southern sites of Nyisky Bay. Eggs are distributed over the spawning area very unevenly. Thus, on the potential spawning grounds near Bauri Island and Cape Medvezhiy the eggs may occur everywhere in some years, and mosaically or be absent at all in other years. At the same time, eggs occur annually near the islands Bayandin and Gafovich. On the main area of spawning grounds in the bay in 1995-1997 the intensity of eggs’ laying was not high (2,0-2,5 thousand egg/m2). The greater numbers of eggs are observed seldom. Only in 1998, on the last-year marine grass near Gafovich Island the density constituted 73,08 - 73,16 thousand ind./m2 at two sites with the total area of 0,06 km2, and in 1999 it was 455,88 thousand ind./m2 on the area of 0,03 km2. The mean- statistic indices of the eggs’ density on the substrate increased due to the above sites. On the main area of the bay the egg density did not exceed a mean long-term level. The mean numbers of eggs on substrate over the bay (except for sites with the high density near Gafovich Island) was 1,0-2,5 thousand egg/m2. Despite the rather severe conditions for spawning and embryonic development, eggs mortality in the bay was 0,4 - 2,1 %, on average during sampling (Table 4.9.9) (Andreev, 1963б; Frolov, 1965; Schukina et al., 2000). During the incubation period continuing 11-12 days, on average, a significant part of eggs (more than 70 %) perish. Practically at once after emerging, herring larvae are carried out to the sea with the tidal currents. After spawning the local herring feed on the northeastern Sakhalin shelf. During the summer, herring occur periodically in channels and bays. Herring’s enters the bay are connected with unfavorable hydrologic conditions for feeding in the sea (Frolov, 1950, 1964, 1968б; Gritzenko, Shilin, 1979). By our data (Zverkova et al., 1997), a group of 25 to 28

СахНИРО Отчет по договору Y-00571 147 cm was the most abundant in June 1995 in the size series of the Nyisky Bay herring; in June 1996 a group of 22 to 27 cm. In July – September, juveniles 5-15 cm long may occur in the bay. In September 1995, specimens of 8 to 19 cm were found; a group of 10 to 13 cm long was the dominant. In winter, herring occur periodically in the bays too.

Table 4.9.9 Numbers of herring eggs on substrate in the Nyisky Bay, ind./m2 Year 1995 1996 1997 1998 1999 min 1 355 2 512 7 1 978 463 max 4 950 2 444 4 544 73 164* 455 882* mean 2 567 2 478 1 077 20 882 22 862 mean mortality, % 0,4 No data 0,7 2,1 0,5 *on the limited area near Gafovich Island

A fishing of the spawning herring in the Nyisky Bay begins immediately after the ice disappearing in the bay and flood cessation on the Tym River. In the bay, nets are settled after 23 of May, when strong approaches of herring for spawning and their high catches are observed. To our opinion, a fishery statistic reflects rather well the intensity of spawning run. In general, daily catches characterize numbers and dynamics of approaches for the spawning herring. The main part of the herring stock spawns in the first half of June; this is proved by the catch sizes. Thus, by 10 June the mean catch is 53,3 % of the total catches, and by 20 June it reaches 83,0 %. By the end of June a spawning of the main part of herring stock completes and, consequently, the fishing (Schukina et al, 2000). The first and most powerful catches are annually observed in the last decade of May near Cape Bauri. Then, as usual, fish appear near Cape Medvezhiy in the first decade of June. In the last turn, usually in the second decade of June, fish occur near the sandy spit in the region of MPS. Mass enters of herring, as a rule, are timed to the periods of quadrature tides. In the period of spring tides (so called “double waters”) the minimum catches are recorded, or herring do not enter the bay at all (Frolov, 1965; Gritzenko, Shilin, 1979). A spawning period has a well expressed wavy character of herring approaches; usually, 2-3 peaks are noted (Vedensky, 1950; Andreev, 1963а; Gritzenko, Shilin, 1973). The fishing is realized in the period of mass spawning run of herring; exclusively this species occurs in nets. In addition, eastern and big-scaled redfins, Asiatic and pond smelts occur in catches in the first half of June. In the second half of June, starry flounder and flathead sculpin prevail in bycatches in the second half of June; saffron cod occur too. A summarized catch of different fish species in the bycatch does not exceed 3,0-5,0 % of the total catch. A capture of herring in the bays is realized almost exclusively by the fish collective farm “Vostok”. The attempts to interest small private fishing enterprises, including aboriginal ones, did not give positive results in herring study and its capture due to the weak organization of works by these enterprises. From 1 to 3 small fixed nets have been settled in the Nyisky Bay since 1987. Locations of their settlement remained the same for all the years of observations: capes Bauri and Medvezhiy, and region of MPS on the sandy spit Plastun. If one net was settled, it was located in the region of Cape Bauri.

Saffron cod A dominant size group of saffron cod was represented in June 1995 by specimens of 19,0 to 26,0 cm long, and in September of the same year by two groups: 18,0-19,0 cm and 26,0-28,0 cm (Zverkova et al., 1997). Saffron cod lengths varied from 20,5 cm in 1988 to 27,5 cm in 1993 from the commercial catches during the winter (Fig. 4.9.1). Immature saffron cod dominate by numbers in the summer-autumn period, and adult specimens in winter.

СахНИРО Отчет по договору Y-00571 148 By the data of S.N. Safronov (1986), juveniles of this species consume exclusively planktonic organisms: copepods, euphausiids, hyperiids, and, to the less extent, harpacticides, decapods, and fish eggs. In September 1995, polychaetes and gammarides were the most hfrequent in fish stomachs (more than 10,0 cm), then mysids and shrimps being less frequent (Zverkova et al., 1997). The proportions of polychaetes and small shrimps were almost equal by the weight (35,0 and 30,0%, respectively). 10,0 % of fish had empty stomachs; the index of 0 fullness for feeding fish varied from 92,5 to 102,9 /000. Saffron cod catches in the Nyisky Bay were always low. They varied from 7,9 to 19,2 % in the total catch over the region (see Fig. 7.9.6 in Chapter 7). As a rule, a number of gear in recent ten years has not exceeded 30 units. Catches varied from 1,08 t (2001) to 17,6 t (1990).

29

27 см , 25 АС

23 длина

21 19 17 Средняя 15 1988 1990 1992 1994 1996 1998 2000 2002 Годы наблюдений

Fig. 4.9.1. Dynamics of the mean length of saffron cod in the Nyisky Bay since 1988 through 2002 (except for 1994 and 2001)

Flathead sculpin In June 1995 and 1996, flathead sculpin was represented in catches by specimens of 19,0 to 36,0 cm long (Zverkova et al., 1997). In July 1999, the maximum length of flathead sculpin reached 40,2 cm, weight 1051 g. Lengths varied from 13,8 to 40,2 cm. Body weights varied from 30 to 1110 g. Specimens at the age of 2+ to 8+ were found (Table 4.9.10). Second-year and fifth- year fish prevailed making up by 26,4% of the total number of fish. Growth parameters, by our data, are close to those presented by Volodin (1993, 1999).

Table 4.9.10 Size and weight of flathead sculpin by the age groups in Nyisky Bay in July 1999 Age Limits Index 2+ 3+ 4+ 5+ 6+ 7+ 8+ M Length, lim 138-174 214-252 252-291 290-346 350-360 - - 138-142 mm M 151 237 271 325 354 390 402 304 lim 30,1-78,5 205-284 278-455 485-715 600-952 - - 30,1-1110 Weight, g M 54,7 237 380 635 783 1110 1051 603 n lim 15 6 6 16 3 1 1 48 % M 31,3 12,5 12,5 33,3 6,3 2,1 2,1 100,0

0 The mean fullness of stomachs was 403,39 /000. Amur stickleback (41,4 %) was the most mass in fish stomachs by frequency, eelpout (68,9 %) and herring (14,8 %) by the relative biomass (Table 4.9.11). The base of the flathead sculpin diet was formed by mass species inhabiting the coastal part of the bays, Zostera thicket. Sand shrimps and freshwater sculpins СахНИРО Отчет по договору Y-00571 149 occurred in stomachs of fish caught in the near-mouth parts of rivers. By the data of studies in June 1995 and 1996, and September 1996, the mean fullness of 0 the flathead sculpin stomachs was 250,85 /000. Isopoda (Saduria sp.), making up 48 % prevailed in the diet by frequency. Fishes (juvenile smelts, flounders, salmon, herring, sculpins) exceeding 55,0 % of the food bolus weight dominated by biomass. The rest components constituted less than 5,0% (fish eggs - 4,2, algae -3,5, bivalves -1,1, shrimps - 0,8, mysids - 0,1).

Table 4.9.11 Food components in the flathead sculpin stomachs in July 1999 Mean Mean Frequency, Relative Index of Index of Food object abundance, biomass, % biomass, % fullness, 0/ density ind/stomach g/stomach 000 C. pallasii 24,1 2,29 31,87 14,84 1069,54 358,24 Z. elongatus 3,4 1,00 148 68,92 243,02 237,65 P. sinensis 41,4 2,58 7,05 3,28 2042,82 135,83 C. septemspinosa 10,3 1,00 7,59 3,53 250,46 36,56 S. entomon 13,8 1,25 5,66 2,64 530,97 36,37 G. aculeatus 10,3 1,33 4,03 1,88 352,2 19,4 Gobiidae indet. 3,4 1,00 5,2 2,42 98,52 8,35 Z. marina 6,9 - 1,51 0,70 88,38 4,86 P. tymensis 3,4 2,00 2,1 0,98 39,79 3,37 Gammaridae 6,9 2,50 1,01 0,47 108,15 3,24 Remains of 3,4 - 0,64 0,30 13,10 1,02 bones Min.particles 3,4 - 0,09 0,04 3,71 0,14 Total - - 214,75 100,00 - -

Flathead sculpin is one of the main commercial objects in the bay during the winter period. “Sculpin” catches in the Nyisky Bay constitute from 7,9 to 19,2 % of the total catch over the region (see Fig. 7.9.9 in Chapter 7). A percentage composition of species named “sculpin” is presented in Fig. 4.9.2. A catch of flathead sculpin varied from 50 t (1992) to 165 t (1991), averaged 101 t.

Сельдь

Пол.камбала

Зубастая корюшка

Бельдюга

Пл.бычок

Навага

0 102030405060

% состав "бычка"

Fig. 4.9.2. Species composition of “sculpin” in catches from the Nyisky Bay (by biomass, %) by the data of 1991. СахНИРО Отчет по договору Y-00571 150

4.9.2. Secondary commercial and perspective for fishery species Sakhalin char In July 1999, the main numbers of Sakhalin char were captured in the northeastern part near Kaurunani Island by the beach seine, and by fingerling trawl in the coastal part (Latkovskaya et al., 2001). Fish lengths varied from 17,8 to 56,5 cm, weight from 49 to 1765 g. Specimens at the age of З+ to 9+ were found. Fifth-year (4+) fish prevailed (24,1%) (Table 4.9.12).

Table 4.9.12 Sakhalin char's length and weight from different age groups in the Nyisky Bay in July 1999 Age lim Index 3+ 4+ 5+ 6+ 7+ 8+ 9+ M 17,8- 21,2- 28,0- 36,2- 40,5- 44,8- 52,0- 178- Length lim 21,9 29,0 37,6 39,5 43,3 50,0 56,5 565 mm M 19,8 25,6 32,3 38,1 42,1 46,8 54,3 37 49- 61- 191- 408- 605- 910- 1262- 49- Weigh lim 91 265 654 635 765 1161 1765 1765 t, g M 69 153,6 359 535,2 716,4 1024 1489 627,1 n lim 7 14 12 11 7 4 3 58 % M 12,1 24,1 20,7 19 12,1 6,9 5,2 100

The base of Sakhalin char diet is formed by the most mass species inhabiting lagoon in this or that period. Both marine and brackish hydrobiont species occur in fish stomachs. The most mass species (capelin, in its spawning period, Asiatic and pond smelts, Amur stickleback, and saffron cod) are the main food objects for the Nyisky Bay Sakhalin char. Capelin (75,0%) 0 prevailed by frequency. Index of the char stomachs fullness with this species was Зб01,б4 /000. 0 0 0 Asiatic smelt - 1545,60 /000, pond smelts - 1529,19 /000, and Amur stickleback - 74б,91 /000 0 were the other mass food objects. The mean index of stomach fullness was 827,68 /000 over the region.

Asiatic smelt In June 1995 and 1996, Asiatic smelts of 20,0 to 26,0 cm long prevailed (Zverkova et al., 1997). In September, specimens of 15,0 to 18,0 cm long prevailed. Larger fish occurred in small numbers. In September 1995 and June 1996, Asiatic smelt fed weakly. Major fish had empty stomachs; the mean fullness in September was 0,2. By the data of O.F. Gritzenko (1990; 2002), in summer smelts feed in the bay, and a peak of feeding occurs at night, during the maximum tide. A daily rhythm of consuming has a monocyclic character. Asiatic smelt prefers planktonic organisms for feeding. The greatest proportion of the food bolus mass belongs to Copepoda (92,5%) - Acartia and Eurytemora - respectively 38,4 and 24,1%, Pseudocalanus sp. and Sinocalanus sp. - 5,9 and 5,2%. Cladoceres (Podon sp.) - 18,9% were consumed in great numbers. The near-bottom organisms Mysidacea and Cumacea, making up respectively 4,2 and 3,3% occurred in small numbers.

Starry flounder In 1999, fish lengths varied from 15,0 cm to 38,5 cm (Table 4.9.13), averaged 27,3 cm; fish weights varied from 55,3 to 1115,0 g, averaged 416,5 g (Latkovskaya et al., 2001). The age composition was presented by specimens of 4+ to 11+. The maximum number of fish were at 5+ age. Due to the gear selectivity (nets), specimens from the younger age groups were absent in catches. Mature specimens are distributed over the bay, mainly, along the fairways, as a rule, not far from the straits.

СахНИРО Отчет по договору Y-00571 151 Table 4.9.13 Length and weight of starry flounder from different age groups Age lim Index 4+ 5+ 6+ 7+ 8+ 9+ 10+ 11+ M 150- 175- 214- 246- 265- 305- 380- 150- length lim - 199 232 240 277 295 322 385 385 mm M 168,9 194,3 229,6 256,1 281,1 313 358 373 273,1 55,8- 91,0- 175,5- 234,8- 233,9- 453,0- 785,0- 55,8- weight lim - 110,0 240,0 275,0 448,0 487,0 621,0 1115,0 1155 g M 82,6 141,6 228,9 319,1 398,1 528,0 678,0 950,0 416,5 n lim 6 13 5 9 7 4 1 2 47 % M 12,8 27,7 10,6 19,1 14,9 8,5 2,1 4,3 100

A percentage of fish with empty stomachs was 81,0 %. Their maximum fullness was 0 7022,6 /000. Isopods (57,1 %) prevailed by frequency (Table 4.9.14). Their relative biomass was 33,2%. The previous surveys showed (Zverkova et al., 1997) that juvenile flounders preferred polychaetes (frequency 39,3%), gammarides (frequency 28,6 %), herring eggs in the period of its spawning (frequency 17,9%), and salmon fry during their migration to the sea (frequency 7,1%). By the data of our observations, starry flounder prefers benthos organisms.

Table 4.9.14 Contents of food components in the alimentaly canals of starry flounder Mean Mean Frequency, Relative Index of Index of Food object abundance, biomass, % biomass, % fullness, 0/ density ind./stomach g/stomach 000 Isopoda 57,1 1,8 2,44 33,2 1662,6 1896,3 Mysidae 35,7 3,0 0,79 10,7 662,6 381,0 Amphipoda 50 6,9 1,21 16,4 1519,4 819,4 Macrura 42,9 0,6 1,67 22,7 1239,7 972,5 Bivalvia 7,1 0,5 0,25 3,4 118,4 24,2 Tribolodon sp. 14,3 0,1 0,59 8,0 213,4 115,0 Gasterosteidae 7,1 0,1 0,41 5,6 117,1 40,2 Total 7,37 100

Banded flounder Fish lengths from our catches varied from 15,1 to 31,9 cm, averaged 22,7 cm, weight from 50 to 516 g, averaged 22 g (Table 4.9.15).

Table 4.9.15 Length and weight of banded flounder from different age groups Age lim Index 4+ 5+ 6+ 7+ 8+ 9+ 10+ 11+ M 15,1- 15,8- 18,2- 19,7- 21,8- 27,2- 15,1- length lim - - 15,4 18,0 19,5 21,3 24,3 28,2 31,9 mm M 15,2 17,1 18,9 20,5 22,8 27,7 27,5 31,9 22,7 50,0- 61,0- 99,0- 105,0- 201,0- 275,0- 50,0- weight lim - - 63,0 101,0 165,7 229,7 279,0 516,0 516 g M 56 86,3 129,2 165,2 235,3 395,8 291 400 220,3 n lim 3 13 29 16 5 4 1 1 72 % M 4,2 18,1 40,3 22,2 6,2 5,6 1,4 1,4 100

СахНИРО Отчет по договору Y-00571 152

A diet of banded flounder was studied from the beach seine catches at the northeastern part of Kaurunani Island. Масоmа cf. balthica (27,2 ind./stomach; 11,4 g.; 97,1% of the total biomass of stomach fullness) dominated among all food objects. For species of the first order (Litorina sitkana and Zosiera marina) the density indices were 29,8 and 31,6, respectively. Zostera was consumed when excavating molluscs. The mean number of entire Macoma in stomachs was 10,3 ind./stomach, dead (only shell) - 17,0 ind./stomach (Table 4.9.16).

Table 4.9.16 Contents of food components in the alimentaly canals of banded flounder Mean Mean Relative Frequency, Index of Index of Food object abundance, biomass, biomass, % fullness, 0/ density ind/stomach g/stomach % 000 M. cf. balthica 100,0/100,0* 27,2/17,0* 11,4/7,04* 97,1/92,7* 5536,3/521,3* 9710/9274* L. sitkana 21,1 1,8 0,17 1,4/3,5 24,1 29,8/74,3 Z/ marina 21,1 - 0,18 1,5/3,7 32,4 31,6/78,6 Total - 29 11,76 100 5593 9771 Total (without a - 18,8 4,72 100 5270 94267 shell) *-shell

Pacific eelpout The mean fullness of stomachs and diet composition of Pacific eelpout varied due to the region of fishing. In 1995-1996, the index of stomach fullness with herring eggs (in shallow 0 places of its spawning) was maximum -166,2 /000. Only herring eggs occurred in stomachs. In other regions, Pacific eelpout practically did not feed; to 90,0 % of fish had empty stomachs. Thus, the Nyisky Bay basin is of great fisheries importance. Pacific salmon spawn in rivers flowing into the bay. The largest in this region spawning grounds of pink, chum, and coho salmon are located in the Tym River being the greatest water course in the northeastern Sakhalin Island. There, the abundance of mature chum and coho is significantly greater than in other bays of the island north-east. Anadromous fishes (arctic lamprey, Pacific salmon, and others), migrating far, occur in the bay only during a spawning run of adult fish and their fry downstream migration to the sea. Two hatcheries, artificially culturing Pacific salmon, functionate in the Tym River basin. Other anadromous fishes (Sakhalin taimen, Sakhalin char, Pacific redfins, and others) feed for a long time in the bay, seldom coming to the open part of the sea. In summer, herring spawn in the bay. During a year they feed in the bay, alternating with the outcome to the sea. Juvenile starry flounder, being much abundant on the northeastern Sakhalin shelf, feed in the bay. In the Nyisky Bay, a fishing of Pacific salmon and herring in summer – autumn, and saffron cod and flathead sculpin in winter is conducted. At present, there is a closure for chum fishing. It is captured only within the control catch and by aboriginals. “Sculpin” is prevailed by the volume of capture. The volume of saffron cod and “sculpin” is significantly lower than in the Piltun Bay. At present, fishery companies are not interested in herring capture, partially due to the relatively low density of its aggregations. The amateur fishing is developed in the bay basin: Sakhalin char, southern malma and others in summer and autumn, and Asiatic smelt and saffron cod in winter.

СахНИРО Отчет по договору Y-00571 153 5. NABIL BAY

5.1. General physic-geographic characteristics of the Nabil Bay

The extension of Nabil Bay is about 25 km in length and about 10 km in width. The bay area is 188 km2. This bay is a common semi-closed lagoon separated from the sea by a low sand spit of 150 to 1000 m in width. The channel joining the bay with the sea is named Aslanbekov Strait. The channel is about 10.8 km long, 200-750 m wide, and 2.5-12 m deep. The prevailing depths in the bay are 0.6-1.8 m. The exception is the fairway part, where depths reach 2.5-6.0 m. The main fairway passes along the channel and turns to the west near the northern extremity of the Aslanbekov Peninsula being divided into two branches, one of which is directed to the central part of the bay, another along the peninsula. Approximately in the central part the fairway disappears. The branches of the main fairway pass between Cape Pologiy and Chaika Island and north of Chayachyi Islands. Before the Zalesenniy Island the first branch is divided into two smaller branches directed to the northern and central parts of the bay. The second large branch is directed to the central part of the bay. The Nabil Bay shores are low-lying and swamped on the major part. The exception is a sandy shore in the channel and near the northern extremity of Aslanbekov Peninsula. A hydrographic net is the most developed in the southern part of the bay, where the rivers Orkunyi, Nabil, Vazi, Gamadesh flow. The rivers’ deltas are strongly branched and swamped. On the western coast the Katangli River and several brooks flow into the bay; brooks Ozerny and Mokhoviy are the largest among them. In the north the Mayachniy Brook flows into the bay. By its particle-size composition of bottom sediments, the Nabil Bay is divided into two almost equal parts: northeastern being affected by sea tides, and southwestern being exposed to the influence of a river run-off. The boundary between them passes along the line joining the mouth of Katangli River and the foundation of Aslanbekov Peninsula in the region of Orkunyi Bay. A monomodal distribution of fractions is common for bottom sediments of both parts. Sediments from the northeastern part of the bay were represented, mainly, by medium-sorted fine and medium sands containing the modal fraction of 45-55 %. The bottom grounds from the southwestern part were represented, mainly, by weakly-sorted pulverulent sands and aleuro- pelite sediments containing the modal fraction of 35-45 %. Approximately the same composition of bottom sediments was observed in the stagnant zone around the islands. The greatest influence upon the formation of lagoon hydrologic regime is exerted by the tidal fluctuations of a sea level. In the study region the tidal fluctuations have a daily character, that is, one high and one low tide are being observed during 24 hours. A mean estimate of the daily tide at the entrance of the Nabil Bay makes up about 0.7 m, the maximum estimate 1.5 m. During the tidal waves penetration into the narrow channel, as a rule, a decrease in their amplitudes and increase in their phases take place due to the diffraction and increase in the influence of the bottom and lateral friction. In Nabil Bay the decrease in amplitudes is more significant than the phase shifts. This proves the prevailing of effects, connected with diffraction, over the influence of the bottom and lateral friction. The tidal wave penetration into the lagoon is accompanied with the rise of strong tidal streamline currents. These currents reach the maximum values in the channel, directly at the bay outlet. By the measuring data, their mean values constitute 0.7-0.8 m/sec, and maximum values exceed 1.8 m/sec. The influence of the tidal currents upon the hydrodynamics conditions of the bay is localized in the region of the channel and fairways. Moving off them, the periodic currents are weakened and become hardly noticeable in the wide shallow zones. Besides the tidal phenomena, a sea influence on the hydrodynamics regime of the Nabil Bay is reflected in stormy raising of the water level. The raising origination is caused by 154 meteorological phenomenon: the influence of atmospheric pressure and wind on the sea surface. The greatest raisings are observed in October-November, when their estimates may reach 0.7-1.0 m. As a rule, the raising duration makes up more than 12 hours. During this time period a great volume of seawater enters the bay caused by the activity of the pressing wind. After stopping the activity of factors provoking the raising of the water level, the accumulated water mass flows to the sea out of the bay grasping solid material. The raising effect is usually strengthened by the influence of the heavy sea. The active dynamics of the strait causes a constant change in flow outlet of the Nabil Bay. A northern shore of the channel is being intensively eroded, and a southern part of the spit is inwashed. The mean velocity of the bay outlet shifting to the north is 11.5 m/year by the data of long-term observations. A river run-off affects mainly in the southern shallow part of the bay, where the mouths of major rivers are located. The affect of the river run-off is the greatest during a spring flood, the peak of which occurs, as a rule, in early-May. In this time period the mean estimates of the water rise in rivers reach 0.8-1.0 m; the water occurrence on flood-plain is observed. A period of the spring flood is accompanied by the active flowing of fresh waters and terrigenous run-offs into the bay. In the rest time, including summer and winter low water levels, the water level in rivers do not change significantly, and the volume of water flowing to the bay practically remains invariable.

5.2. Hydrology and hydrochemistry of the Nabil Bay

5.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data Archive data on the Nabil Bay are presented by the results of the reconnaissance surveys during the monitoring works in lagoons and a coastal zone of northeastern Sakhalin in 1995- 1996 (Samatov et al., Scientific report, 1997), results of surveys carried out by the joint scientific expedition of SakhNIRO – “Ecological Company of Sakhalin” in June-July 1999 (Ecological studies…, 2001 г.), unpublished data of the field surveys of the Laboratory of Applied Ecology on hydrochemistry and bay pollution for 1997-1998, and materials of the dissertation work of E.M. Latkovskaya (Latkovskaya, 2000). During the surveys conducted in June 1996, a total of 8 littoral stations have been performed: 3 in the strait, and 5 along the western bay coast. In August, 5 stations were surveyed: 2 in the strait, and 3 along the western bay coast. A temperature regime of the lagoon is determined by the seawater flow through the channel, radiation warming, and in-shore run-off. In the summer period, the lowest water temperatures have been recorded in the deep-water near-strait part of the bay, where the thermal regime is determined by the cold seawater influence. During the survey, a surface water temperature in the channel was 8-10 °С, and moving away from the channel, it increased rapidly, reaching 15-17 °С in the central part of the bay, and 17-27 °С in the shallow zone. A vertical structure of the water temperature field in the bay is characterized by the almost complete homogeneity in the shallow zones and temperature lowering from the surface to the bottom (1-2 °С lesser) in the central part of the bay. In the deep-water part of the channel a temperature contrast between surface and near-bottom layers is more expressed and constitutes 2-4 °С (Ecological studies …, 2001). A salinity regime of the bay water is determined by the joint influence of sea tides and river run-off. The water with more than 20 ‰ of salinity was recorded only in the channel and the edge northeastern part of the bay. In the central part of the lagoon, salinity constituted about 12-14 ‰, and in the southern part declined up to 2-6 ‰. A vertical salinity distribution was rather homogeneous: a salinity gradient was 2-3 ‰ between the surface and near-bottom horizons. This is promoted by the shoal and active water dynamics of the lagoon. 155 In June 1996, pH values varied from 6.68 to 8.43. The maximum estimates were recorded at 3 stations in the strait. There pH varied from 8.30 to 8.43, indexing the commonly sea water. pH value directly in the bay varied within 7.24-7.86. The minimum estimate (6.68) was recorded in the river mouth in the northern heel of the bay; this characterizes the more acid reaction of the river water flowing on peatbogs. On the whole over the bay, the value of pH in the river mouths was minimal (this is also common for other time periods of surveys). In August, the values of pH varied within 7.40-8.50, averaged 7.96. pH distribution was similar: the maximum estimates (>8.00) were recorded in the strait. A number of dissolved oxygen varied from 6,2 to 7,9 mg/dm3. The minimum levels of dissolved oxygen were timed to the northern codened of the bay, being characterized by the plenty of decaying Zostera. Nitrite concentrations in water varied from 0.0 to 14.4, averaged 3.52 mkg/dm3. The maximum estimate was recorded at a station in the northern codened of the bay, where the great aggregations of Zostera occurred. Nitrite nitrogen concentrations in water varied from 1.47 to 5.40, averaged 3.63 mkg/dm3. In September 1998, pH value varied from 8.31 at stations, exposed to the influence of river waters, to 8.90 in places, where the influence of seawaters is the greatest. Ammonium nitrogen concentrations varied from 3.38 to 36.26 mkg/dm3. The maximum estimate was recorded at station near the inlet of the bay, minimum in the northern heel of the bay. Levels of nitrite nitrogen contents varied within 0.0 - 5.18 mkg/dm3. The minimum estimate was recorded in the brook mouth, maximum in the region of influence of seawaters. A content of nitrates in the bay was below a threshold detectability of the method, however, it reached significant estimates at the bay inlet, due to the sea influence. A content of phosphates was maximum in the brook mouth, being affected by the river carry-over. The minimum concentrations of silicates were observed in the region of a freshwater brook mouth, maximum estimates were recorded at the inlet of the bay. Table 5.2.1 shows the data of hydrochemical parameters of the Nabil Bay in September 1998.

Table 5.2.1 Hydrochemical parameters of the Nabil Bay in September 1998, mkg/dm3 рН Nitrogen ammoniu Nitrogen Nitrogen Phosphor Region of sampling m nitrite nitrate us mineral Silicon Northern codened 8.31 3.38 3.64 0.00 80.10 559.16 Western coast, mouth of Ozerny River 8.80 24.08 0.00 0.00 298.20 211.40 Bay inlet (channel) 8.90 36.26 5.18 112.70 52.80 686.56

In June 1999, the most full-scale survey of the bay was carried out together with the Ecological Company of Sakhalin. The range of hydrochemical indices is shown in Table 5.2.2. A distribution character of hydrochemical parameters over the bay area was caused by the tide phase and distance from river mouths and a sea. Table 5.2.2 Hydrochemical indices of the Nabil Bay in June 1999 Index Min Max Average Suspended matters, mg/dm3 9.78 79.81 40.42 Dissolved oxygen, mg/dm3 6.28 7.33 6.93 3 BOD5, mlО/dm 0.28 4.14 2.58 Oxidation, mlО/dm3 5.74 11.80 7.96 Phosphorus general, mkg/dm3 34.00 112.50 69.31 Phosphorus mineral, mkg/dm3 1.00 89.50 39.87 Рhosphorus organic, mkg/dm3 0.00 86.00 33.33 Silocon, mkg/dm3 721 3990 2444 Chlorophyll a, mg/dm3 1.28 15.32 5.74 156

3 A content of dissolved oxygen varied from 6.28 to 7.33 mg/dm . The BOD5 value varied within 0.28 - 4.14, averaged 2.58 mlО/dm3; this is common for waters with a great content of organic matters. The maximum estimates were recorded in regions of accumulation of slimy sediments and in places of Zostera aggregations. Estimates of the water oxidation ranged within 5.74 -11.8, averaged 7.96 mlО/dm3). The maximum levels of phosphates and silicates were observed in the south of the bay, where the role of river run-off was the most expressed. The maximum concentrations of chlorophyll a were observed in the channel.

5.2.2. Results of hydrologic-hydrochemical researches in 2002 Results of hydrologic-hydrochemical analysis of samples from the Nabil Bay are given in Appendix 5.2.1. Some statistic characteristics of the determined parameters are illustrated in Table 5.2.3.

Table 5.2.3 Some statistic characteristics of the determined ingredients from the Nabil Bay

Ingredients Xav Xmax Xmin Depth, m * 7.0 0.3 Temperature, °С 11.0 12.4 10.0 Salinity, ‰ 15.6 23.7 2.4 pН value 8.13 9.17 6.80 Dissolved oxygen, mg/dm3 9.70 11.60 8.32 Nitrogen nitrite, mkg/dm3 < 0.5 1.6 < 0.5 Nitrogen nitrate, mkg/dm3 8.9 25.4 < 5.0 Phosphorus (orthophosphates), 20.2 40.1 9.0 mkg/dm3 Silicon, mkg/dm3 718.1 1660.0 203.5 Mass concentration of petroleum < 0.005 0.012 < 0.005 products, mg/dm3 Suspended matters, mg/dm3 14.94 46.05 2.35 Chlorophyll а, mkg/dm3 2.51 6.20 0.58 * insufficient data for calculating the mean value

The water temperature of the Nabil Bay varied from 10.0 to 12.4 °С. The maximum temperature was recorded at the shallow station 4, minimum at the deepest station 1 in the channel, joining the strait with the sea. On the whole, an insignificant increase in temperature to the center of the bay was observed. Salinity gradually decreased from the north of the bay to the south, when moving away the surveyed stations from the channel. The maximum estimate (23.7 ‰) was observed in the channel, minimum (2.4 ‰) at the very southern station; evidently, this was caused by the water inflow from the Nabil River and small rivers and brooks. The mean salinity estimate was 15.6‰. pH value ranged widely from 6.80 to 9.17. The maximum estimates were recorded at shallow stations 4 and 8 (depth 0.6 – 0.8 m). This was, evidently, a consequence of the intensive phytoplankton development, and algae in general, under the higher temperature, being proved by a high oxygen concentration in the water sample at this station. pH value was minimal at station 7, where the bay water is diluted by the inflow of waters from rivers Nizhnaya Vazi and Nabil containing humus matters from the adjoining swamped territories. The mean pH value of the bay was 8.13. From surface to near-bottom horizons pH value declined everywhere. Concentrations of dissolved oxygen varied from 8.32 (a near-bottom horizon of station 6) to 11.60 mg/dm3 (a surface horizon of station 7). The mean estimate over the bay was 9.70 157 mg/dm3. We could not reveal a definite character of the oxygen distribution over the surface. When being distributed by depths, the dissolved oxygen concentration declined from surface to near-bottom horizons. A content of nitrite nitrogen in water samples was minimal in major cases, concentrations were below the method sensitivity (< 0.5 mkg/dm3). Nitrite nitrogen was found only in samples from stations (1, 2, 3) located close to the channel joining the sea and the bay, that was caused, probably, by the most intensive processes of production and consumption in places of sampling (1.0 – 1.9 mkg/dm3), and a concentration close to minimal (0.6 mkg/dm3) at station 8. The mean estimate of nitrite concentrations was 1.6 mkg/dm3. A content of nitrate nitrogen ranged widely from the minimum < 5.0 mkg/dm3 (below the method sensitivity) to maximum 25.4 mkg/dm3. Nitrate nitrogen was found at all stations located closely to the channel (analogously to nitrite nitrogen). The maximum content was found at station 6 (a central part of the bay). Concentrations of phosphorus (orthophosphates) in water samples of the bay varied from 9.0 to 40.1 mkg/dm3. The maximum estimate was recorded at station 3, minimum at station 9. The mean estimate of concentrations was 20.2 mkg/dm3. We could not reveal a definite character of the phosphates distribution over the surface and depths. A content of silicon varied from 203.5 to 1660, 3 mkg/dm3. The maximum estimate of concentrations was recorded at station 6, minimum at station 4. The mean estimate of concentrations was 718.1 mkg/dm3. Evidently, due to the intensive confusion of water masses, a definite character of the silicon distribution over the bay area was not revealed. Examinations of water samples from the Nabil Bay for petroleum hydrocarbon contents revealed their occurrence in samples of deep-water stations (1, 2, 9) located in the channel (0.006–0.030 mg/dm3) and at the outlet from the bay, and also in a sample from station 9 located in the northern part of the bay. In the rest cases, concentrations of petroleum hydrocarbon occurred below a threshold detectability of the method (< 0.005 mg/dm3). Distribution patterns of suspended matters in water samples of the bay were heterogeneous, concentrations varied from 2.35 to 46.05 mg/dm3 (stations 7, surface and near- bottom layers, respectively). The mean estimate was 14.94 mg/dm3. The mean chlorophyll-a concentration was 2.51 mkg/dm3, varying widely from 0.58 (station 7, surface) to 6.20 mkg/dm3 (station 4). The increase in chlorophyll-a concentration from surface to near-bottom horizons was observed in distribution by horizons. Thus, the estimates of concentrations of all the determined ingredients were within the standard or significantly lower the tolerance limited concentrations (List of fisheries standards …, 1999); often the concentrations of determined parameters were below a threshold detectability of the method. pH value of the bay varied widely, that is, probably, a consequence of intensive phytoplankton development, on one hand, and washing away humus compounds from the swamped coastal territory, on the other hand.

5.3. Particle-size composition of bottom sediments in the Nabil Bay

By the data of studies in June 1996, the ground in the strait was represented by coarse and medium sand with a touch of fine sand; in the bay it was represented by fine sand with a touch of silty and detritus particles. In August the ground in the strait was represented by medium sand with a touch of fine sand; in the bay it was represented by fine sand with a touch of silty particles. During the survey in June 1999, a total of 25 samples of bottom sediments were collected for analyzing a particle-size composition. As a result of correlation analysis (Ecological studies …, 2001), 6 compounds of the bottom sediment (BS) fractions were distinguished: - pebble, gravel (more than 2 mm); - graveled and coarse sands (2 – 0.5 mm); - medium sand (0.5 – 0.25 mm); 158 - fine sand (0.25 – 0.05 mm); - pulverulent sand (0.1 – 0.05 mm); - dust, clay (less than 0.05 mm). It was noted that a composition of bottom sediments of the bay was determined, to the great extent, by the location of sampling stations relatively to zones of hydrodynamics activity. Sediments of a gravel-pebble fraction occurred in the northeastern part of the bay; their maximum numbers were concentrated along the northern extremity of Aslanbekov Peninsula, exposed to the greatest hydrodynamic influence under the moving of a tidal wave in the bay. The higher content of a gravel-pebble fraction was also observed in the channel and near the islands in the region of the fairway. Analogously to gravel-pebble fraction, the fractions of graveled, coarse and medium sand were distributed over the bay area. Fine sand was distributed evenly enough over the bay area; its content in samples practically everywhere constituted 20-50 %, and only in the southern part of the bay a content of the fine sand fraction decreased to 5-15 %. Particles of 0.1-0.05 mm in size prevailed in the southwestern part of the bay, where their contents in samples reached 50-70 %, and outside the fairway around the islands. Fractions less than 0.05 mm were distributed approximately in the same way. It is concluded that by the particle-size composition of bottom sediments the Nabil Bay is divided into two approximately equal parts: northeastern, being under the influence of sea tides, and southwestern, exposed to the influence of the river run-off. A boundary between them is a line connecting the mouth of Katangli River and the foundation of Aslanbekov Peninsula in the region of Orkunyi Bay. A single-modal distribution of fractions was common for bottom sediments from the both parts. Sediments of the northeastern part of the bay were represented, mainly, by medium-sorted fine and medium sands with the content of modal fraction of 45-55%; bottom sediments of the southwestern part were weakly-sorted pulverulent sands and aleuro-pelite sediments with the content of modal fraction of 35-45 5 %. Approximately the same composition was observed in the stagnant zone around the islands.

5.4. Content of pollutants in the Nabil Bay

5.4.1. Content of pollutants in bottom sediments by the archive and literary data Petroleum hydrocarbons In June 1996, the summarized estimates of PHC varied from 103 to 1600 mkg/g (Table 5.4.1). The minimum estimates of PHC concentrations were observed in the channel (103-116 mkg/g). The maximum estimate was recorded in the northern codened (top part) of the bay (the maximum level of COP accumulation was recorded at the same station). The maximum concentration of petroleum resinous matters was found there too; this proves a man-caused source of PHC inflow. In general over the bay, the major part of total PHC was made up by the non-volatile hydrocarbons (56 – 87 %, on average, 62.3 %). Concentrations of polycyclic aromatic hydrocarbons (PAHC) varied from 0.14 to 2.25 mkg/g, averaged 0.71 mkg/g.

Table 5.4.1 Content of PHC in the Nabil Bay bottom sediments in 1996, mkg/g of the dry weight PHC group June August min max mean min max mean Non-volatile hydrocarbons 80 910 266 40 530 192 Resinous matters 13 690 161 0.2 320 85.4 Summarized content of PHC 103 1600 427 57 900 277 PAHC 0.14 2.25 0.71 0.01 1.78 0.74

In August, concentrations of PHC decreased and varied from 57 to 900 mkg/g, averaged 192 mkg/g (Table 5.4.1). Their distribution over the bay was analogous to the previous survey: 159 the minimum estimates in the channel, maximum in the mouth of Ozerny River. The minimum portion of resinous matters was recorded in the channel. In August a portion of resinous matters reduced. In general over the bay, a portion of non-volatile hydrocarbons varied from 62 to 99 %, averaged 69 %. In the Nabil Bay, rather high concentrations of individual PAHC were recorded (Table 5.4.2), which could be disposed in order by their contents in bottom sediments: fluoranthene (747 ng/g) > benz(в)fluoranthene (396 ng/g) > benz(а)anthracene (287 ng/g) > perilene (148 ng/g) > benz(а)pirene (124 ng/g).

Table 5.4.2 Concentrations (ng/g) and ratio (%) of PAHC in the Nabil Bay bottom sediments in 1996 PAHC min max mean % Acenaphthylene 0.6 35 5 0.82 Acenaphthene 2 22 5 0.82 Fluorene 4 91 22 3.60 Phenanthrene 9 70 30 4.91 Anthracene 4 242 64 10.47 Fluoranthene 4 747 130 21.28 Pirene 4 109 39 6.38 Benz(a)fluorene 0.5 16 2 0.33 Benz(а)anthracene 5 287 56 9.17 Chrysene-triphenylene 13 109 24 3.93 Benz(в)fluoranthene 29 396 115 18.82 Benz(k)fluoranthene 2 67 24 3.93 Benz(a)pirene 6 124 46 7.53 Perilene 3 148 49 8.02

The higher portion of these components in PAHC composition indicates the existing source of a man-caused pollution, which, probably, is connected with the economic activity on the bay coast. In 1999, a content of petroleum products in the bay bottom sediments was determined at 8 stations. A total content of petroleum products varied from 0.0 to 0.2 mkg/g, averaged 0.07 ± 0.07 mkg/g. The higher contents were recorded in the southwestern part of the bay, and in the northeastern part the concentrations declined everywhere. Chlorogranic pesticides In June 1996, the summarized concentrations of chlorogranic pesticides in the Nabil Bay bottom sediments varied from 0.06 to 0.81 ng/g of the dry weight. The mean content was 0.73 ng/g of the dry weight; the maximum concentration (0.81 ng/g) was observed in bottom sediments close to the mouth of a river, which flowed out of Katangli Lake, the place of the active inshore oil workings. Alpha- and gamma-isomers HCCH and p,p of DDT metabolites (p,p-DDE, p,p-DDD and p,p-DDT) were found in the bottom sediment samples. The lowest levels of COP (below a threshold of detectability of the method practically for all the compounds) were recorded in the strait bottom sediments (at the outlet of the bay). In several hundreds of meters, near the pier, the COP concentrations increased an order of magnitude and constituted 0.60 ng/g. In August, concentrations of COP in the bay bottom sediments varied from 0.0 to 0.1 ng/g of the dry weight. The mean content of COP constituted 0.05 ng/g of the dry weight, which was significantly lower compared to June (Table 5.4.3). The maximum estimate was recorded at a station located on the spit and constituted 0.1 ng/g of the dry weight. Only two forms of COP (alpha-HCCH and p,p-DDE) were recorded among 9 examined ones. Thus, a content of COP was higher in June, and a qualitative composition was more diverse in June too (5 forms) compared to August (3 forms). 160 PCB were not found in both seasons. Table 5.4.3 Concentrations of chlorogranic pesticides in the Nabil Bay bottom sediments in 1996 (ng/g of the dry weight) Period Index α- γ- β- о,p- p,p- о,p- p,p- DDT Σ COP HCCH HCCH HCCH DDE DDE DDD DDD June Х av. 0.16 0.13 n.f. n.f. 0.02 n.f. 0.08 0.07 0.45 n=7 Σ 0.09 0.11 n.f. n.f. 0.05 n.f. 0.16 0.12 0.24 Max 0.32 0.27 n.f. n.f. 0.12 n.f. 0.44 0.30 0.81 Min 0.06 n.f. n.f. n.f. n.f. n.f. n.f. n.f. 0.06 August Х av. 0 n.f. n.f. n.f. 0.03 n.f. n.f. n.f. 0.03 n=5 Σ 0 n.f. n.f. n.f. 0.04 n.f. n.f. n.f. 0.05 Max 0.01 n.f. n.f. n.f. 0.10 n.f. n.f. n.f. 0.10 Min n.f. n.f. n.f. n.f. n.f. n.f. n.f. n.f. n.f. n- number of stations n.f.- not found

In 1999, 8 samples were analyzed. During the survey, COP were found at 4 stations; all 5 compounds were found of 5 examined. The mean total content of pesticides in the bay grounds was 0.89 ± 1.31 ng/g. The maximum of the summarized COP concentrations was recorded in the mouth of Mayachniy Brook, flowing over the territory of the wood storage and oil tanks in the settlement Kaigan.

Organic carbon in bottom sediments In 1999, contents of organic carbon in the bay varied from 0.0 to 6.6 %. The mean estimate of concentrations was 2.0 ± 1.7 %, coefficient of variation 84.5 %. On the major part of the bay area concentrations of organic carbon were distributed evenly and varied within 1.5 – 2.5 %, excluding two areas of the higher concentrations: clay sediments on the littoral area in the region of Zalesenniy Island and silty sediments in the extreme southern part of the bay. In order to determine a source of inflow of organic matters, a correlation analysis was carried out, which proved the absence of anthropogenic sources of organic inflow (Ecological studies of the bays…, 2001).

Phenols In June 1996, the phenol concentrations in bottom sediments of the Nabil Bay varied from 0.2 to 8.2 mkg/g of the dry weight. The mean content of phenols in grounds of the study water body was 2.21 mkg/g, which was much lesser than in Chaivo and Nyisky bays. The maximum estimate was recorded in the north of the bay (codened part, close to the mouth of a river passing through the motor road and Nabil port). In addition, during sampling the water of this river was noted to have dark brown color (due to its draining the peaty land).

Metals Statistic parameters of the gross content of metals in grounds of the study water body in June and August 1996 are presented in Table 5.4.4. It was noted that the concentrations of elements in the Nabil Bay grounds were a little higher in June compared to August. By the level of accumulation in the Nabil Bay bottom sediments in June, metals can be ordered in the following way: Al > Fe > Ti > Ba > Mn > Cr > Ni = Zn > Cu > Pb > Co.

161 Table 5.4.4 A gross content of metals in the Nabil Bay grounds, 1996 (mkg/g of the dry weight) n Season Index Al, % Fe, % Ti, % Ba Mn Cr Zn Ni Cu Pb Co 8 June Х av. 3.90 0.63 0.067 529 110 65.5 33.8 40.0 20.9 16.5 2.96 σ 0.60 0.240.041 107 87 17.331.4 9.38 4.76 3.9 3.17 min 3.02 0.35 0.041 350 33 42.0 11.0 33.0 17.0 12.0 0.50 max 4.54 0.89 0.124 680 270 94.0 86.0 59.0 29.0 23.0 9.60 5 August Х av. 4.24 0.55 0.093 612 59 54.6 14.7 35.0 18.2 16.4 3.08 σ 0.54 0.220.045 55 27 37.45.03 1.87 1.10 1.5 1.08 min 3.50 0.33 0.044 530 27 30.0 7.40 33.0 17.0 15.0 2.10 max 4.71 0.86 0.140 660 88 120 20.0 38.0 20.0 18.0 4.20

In June, metals were distributed over the area very unevenly. The maximum scatter of estimates was common (in a decrease order) for Zn, Mn, Ti (Сv >50 %), minimum for Al. The maximum concentrations of major elements were observed at a station located in the mouth zone of a small brook. There the high levels of Сорг. content (10.8 %) and thin fraction of ground <0.05 mm (66.6%) were recorded. The ground was a detritus with a smell of hydrogene sulphide and decomposing residuals of Zostera. Metal concentrations in bottom sediments of the strait and proper bay in this time period, as well as a particle-size composition of sediments from these places, differed greatly. Bottom sediments of the strait were represented, mainly, by coarse and medium sand with a touch of pebble and gravel. Closer to the outlet of the bay, coarser were the bottom sediments. The bay grounds contained significantly more a thin fraction, and that was why they were enriched with Fe, Mn, V and Zn. Numbers of the rest metals in the strait bottom sediments and a proper bay were close. By August, a distribution of metals over the bay area became more even; this was proved by a decline in Cv values for all the metals (except for chromium). In June, for example, a coefficient of variation for V was 96 %, in August it declined to 56 %. At the same time, Cv for Сr in June was 26.4 %, in August 68.4 %. The maximum scatter of estimates in late summer was common for Cr and V concentrations, minimum for Ni and Cu. A comparison of metal concentrations in strait and in bay in August showed that a microelement composition of bottom sediments practically did not differ. In August a ratio between metals changed, and they could be ordered in the following way by their contents in grounds: Al > Fe > Ti > Ba > Mn = Cr > Ni > Cu = Pb = Zn > Co. In June 1997, the grounds were surveyed at 10 stations, and in September at 4 stations for a content of acid-dissolved forms of metals. Statistic parameters of concentrations of the active metal forms in bottom sediments of the study water body are given in Table 5.4.5.

Table 5.4.5 Concentrations of the metal acid-dissolved forms in the Nabil Bay bottom sediments in 1997 (mkg/g of the dry weight) Period Index Al, % Fe, %Ba Mn Zn Cr Ni Cu Pb Cd Hg June mean 4.38 4.10 11147.3 12.3 14.9 6.58 2.67 1.91 0.0610.011 n=10 st.dev. 3.77 3.28 12.146.3 11.2 12.2 9.24 3.19 1.46 0.0760.002 min 0.88 1.00 90 10 4.0 3.2 1.00 0.20 0.40 0.0060.009 max 12.60 10.00 130 140 34.0 40.0 26.00 10.00 5.00 0.226 0.015 September mean 1.43 2.83 13512.3 6.05 7.00 2.55 0.58 0.85 0.0370.015 n=4 st.dev. 0.59 1.82 13.55.85 1.95 1.41 1.84 0.43 0.50 0.0230.004 min 0.80 1.50 1156.00 4.00 5.00 0.60 0.30 0.60 0.0060.009 max 2.20 5.40 14519.00 8.00 8.00 4.80 1.20 1.60 0.0580.018

162 In June, concentrations of major metals were higher in the bay grounds compared to the channel, especially Fe, Cu and Cd. In September, differences in contents of major metals decreased, that is, metals were distributed more evenly over the area. Analogously to the results of the 1996 survey, concentrations of the major elements in the Nabil Bay grounds were higher in June (except for Ba and Hg) compared to September. In 1998, a microelement composition of the bay ground was studied at 6 stations located both in the channel and proper bay (Table 5.4.6). Maximum levels of accumulation of the major metals were recorded at a station located in the end of the channel in a zone of thin sediments, and Zostera field, opposite the outlet of a small brook. Bottom sediment were represented there by silty sand with the maximum content of aleuro-pelite fractions (79 %). In general, a content of elements-tracers of the terrigenous run-off in the channel grounds was lesser than over the bay.

Table 5.4.6 Concentrations of the metal acid-dissolved forms in the Nabil Bay bottom sediments in September 1998 (mkg/g of the dry weight) Index Al, % Fe, % Ba Ti Mn Zn Cr Ni Cu Pb Co Cd Hg Xav 2.88 4.07 12831.7 31.5 11.211.7 5.50 1.57 1.08 2.17 0.037 0.018 st.dev 2.56 3.93 21 33.733.9 10.98.4 7.02 2.00 0.62 1.17 0.035 0.003 min 1.00 1.80 10010.0 12.0 4.03.4 1.40 0.40 0.40 1.00 0.006 0.015 max 8.00 12.00 150100.0 100.0 33.0 28.0 19.60 5.60 2.00 4.00 0.103 0.020

In June 1999, the most full-scale survey of the bay was carried out together with the Ecological Company of Sakhalin. A total of 35 samples of bottom sediments were analyzed for the content of heavy metals in June 1999. The mean concentrations of individual metals in bottom sediments of the bay and other regions of the northeastern Sakhalin shelf and World Ocean are presented in Table 5.4.7. The analysis of the given data shows the higher concentrations of major active metal forms in comparison with the sandy sediments of northeastern Sakhalin shelf and Japan Sea, analogous to concentrations in the aleuro-pelite sediments of the northeastern Sakhalin shelf, and lower in comparison with concentrations in bottom sediments of the World Ocean.

Table 5.4.7 Mean contents of the metal acid-dissolved forms in bottom sediments of Nabil Bay and other regions of Far East seas and World Ocean, mkg/g Region Fe, % Al, Mn Zn Cr Ni Cu Co Pb Cd Hg % Nabil Bay, 6.52 5.00 69.4 21.8 17.7 16.3 5.9 2.7 1.50 0.04 0.012 1999 Nabil Bay, 4.10 4.25 47.3 12.3 14.9 6.6 2.7 1.5 1.91 0.06 0.011 1997 Kirinskaya 11.30 33.2 17.0 10.3 8.0 9.3 0.93 <0.1 0.015 area Piltun-Astokh 1.40 4.4 3.4 0.5 0.5 0.50 0.20 0.026 area Amur Bay 1.30 37.0 9.0 0.8 1.3 1.0 2.10 0.13 Oceanic 95.0 72.0 52.0 33.0 19.00 0.17 0.19 sediments

A correlation analysis showed an expressed positive relation between the concentration of acid-dissolved metal forms, particle-size composition, and depth (coefficient of correlation 0.7 and higher); this proved that metal concentrations were determined, mainly, by sorption abilities of bottom sediments. 163 A comparative analysis of the content of acid-dissolved metal forms in different types of bottom sediments was carried out. By the content of microelements, BS were distributed in the following order: clay < loam < sand (Table 5.4.8).

Table 5.4.8 Mean contents of the metal acid-dissolved forms in different types of bottom sediments of Nabil Bay in June 1999, mkg/g Type of BS Fe, % Al, % Mn Zn Cr Ni Cu Co Pb Cd Hg Clay 10.65 11.40 139.5 50.0 26.6 23.0 10.0 5.0 6.0 0.13 0.027 Loam 8.16 5.88 88.5 26.0 25.5 24.6 7.0 3.7 1.2 0.06 0.011 Sand 3.96 2.87 34.6 11.9 7.1 5.4 3.9 1.0 2.9 <0.050.012

A comparative analysis of microelement composition of bottom sediments, due to their location relatively to the main zones of dynamics activity was carried out (Table 5.4.9). Regarding to the level of influence of dynamics factors, the following three zones were distinguished: fairway – exposed to the constant tidal affect; shore – affected, mainly, by storms; proper bay – the least exposed to the influence of mentioned factors.

Table 5.4.9 Mean contents of the metal acid-dissolved forms in bottom sediments due to the location of stations in Nabil Bay in June 1999, mkg/g Location of Fe, Al, Mn Zn Cr Ni Cu Co Pb Cd Hg stations % % Shore 5.61 3.96 48.9 15.2 12.0 9.6 4.8 1.60 3.0 0.04 0.011 Fairway 2.68 1.46 22.1 8.9 3.9 2.9 2.6 0.60 0.3 <0.05 0.011 Bay 9.37 7.78 112.4 34.8 29.9 29.2 8.6 4.68 3.6 0.06 0.016

By the level of pollution with heavy metals, different parts of the bay can be ordered in such a way: bay > coastal zone > fairway.

5.4.2. Content of pollutants in biota Metals in Zostera Japanese zostera is a mass species very suitable for bioindication. By the level of accumulation in Zostera in 1996, metals can be ordered in such a way: Zn>Cr>Cu>Сd >Pb. Concentrations of elements in leaves of marine Zostera, collected during the ebb in the channel, were low. Their contents are presented in Table 5.4.10.

Table 5.4.10 Metal contents in leaves of Japanese zostera from the Nabil Bay, mkg/g of the wet weight Period Station Zn Cu Pb Cd Cr Ni Fe Mn August 1996 Channel 1.8 0.85 0.11 0.28 1.6 - - - June 1997 End of channel 32.6 3.00 1.25 0.38 2.60 1.5 5230 38 Beginning of June 1997 channel 31 6.00 1.25 1.00 1.50 0.5 1650 85 September 1998 Northern heel 19 2.00 1.25 1.00 1.00 1.0 500 250 September 1998 Channel 25 3.00 1.25 2.50 0.50 0.5 300 300 June 1999 Channel 27.25 12.71 1.42 1.21 - - 810 49.8 Central part of June 1999 the bay 27.22 5.08 3.89 1.28 - - 658 133 164

In 1997, a metal content in Zostera leaves was studied at 2 stations of the bay channel (Table 5.4.10). Differences in the microelement composition in leaves of the marine Zostera were caused by the geochemical peculiarities of sampling places (Latkovskaya, 2000). Thus, plants occurring at the inlet into the channel contained more copper, cadmium, and manganese, which, evidently, were the markers of sea influence. Iron, nickel, and chromium were more in grass at a station located farther from the inlet to the bay and, consequently, more exposed to the terrigenous run-off activity. In 1998, plants, collected in the bay codened, contained more chromium, nickel, and iron. Zostera, collected in the channel, contained the higher levels of zinc, copper, cadmium, and manganese; this corresponded to the 1997 observations: plants, collected closer to the sea, indexed the influence of seawater, and grass, collected farther from the sea – the activity of terrigenous run-off. By the results of the 1999 surveys, a comparative analysis of the obtained data shows that copper and iron concentrations were significantly higher, and concentrations of lead and manganese lower in the leaves of Zostera from the channel compared to the bottom sediments in the central part of the bay (Table 5.4.10).

Metals in tissues of molluscs and fishes In order to study a metal content in gastropods, a mass species (Cryptonatica janthostoma) common for all the bays was chosen. A total mollusc, including its hard tissues, was taken for analysis. Metal concentrations in this mollusc were low and reflected the region geochemistry (Fig. 5.4.1).

1000

100

10

1 Al Cd Co Cr Cu Fe Mn Ni Zn

0,1

Fig. 5.4.1. A mean content of metals in Cryptonatica janthostoma, mkg/g of the dry weight

When analyzing a content of metals in muscles and liver of two fish species from the Nabil Bay, it was noted that concentrations of cadmium, copper, iron, nickel, and zinc were lower, and chromium higher in muscles than in liver (Fig. 5.4.2).

165

1000 бычок плоскоголовый Мышцы Печень 100

10

1 Cd Cr Cu Fe Ni Pb Zn

0,1

1000 навага Мышцы Печень 100

10

1 Cd Cr Cu Fe Ni Pb Zn

0.1

0.01

Fig. 5.4.2. Concentrations of metals in fish tissues from the Nabil Bay, September 1998 (mkg/g of the dry weight) (logarithmic scale) 166 The obtained estimates were lower than MTL (metal tolerance level)(except for cadmium and zinc in a sculpin muscles). In 1999, a content of metals was studied in three fish species: eelpout, starry flounder, and flathead sculpin (Fig. 5.4.3). It was noted that concentrations of cadmium, copper, iron, and manganese were higher in liver than in other tissues; concentrations of copper, cadmium, manganese, and nickel – in flounder muscles; zinc concentration – in eelpout muscles. Several obtained estimates were higher than MTL (zinc – in eelpout liver, copper – in flounder muscles, cadmium – in flounder liver, and chromium – in sculpin liver).

бычок плоскоголовый Мышцы 1000 печень

100

10

1 Al Cd Cr Cu Fe Mn Ni Zn 0,1

0,01

Мышцы 1000 камбала звездчатая печень

100

10

1 Al Cd Cr Cu Fe Mn Ni Zn

0.1

1000 бельдюга Мышцы печень

100

10

1 Al Cd Cr Cu Fe Mn Ni Zn

0,1

0,01

Fig. 5.4.3. Concentrations of metals in fish tissues from the Nabil Bay, June 1999 (mkg/g of the dry weight) (logarithmic scale) 167 5.4.3. Content of petroleum hydrocarbons in bottom sediments in 2002 Results of analysis of the bottom sediment samples for the content of petroleum products in the Nabil Bay are given in Table 5.4.11.

Table 5.4.11 A summarized concentration of petroleum products in samples of bottom sediments and results of the analysis quality control № st Concentration of Mean divergence Extraction of ersatz standard, % petroleum products, of duplicates, % mkg/g Mean Relative standard deviation 1 0.66 26 82 14 2 21.7 3 11.2 4 4.33 5 7.95 6 1.97 5.1 95 22 7 3.61 8 8.91 9 19.8

As one can see from the given Table, petroleum hydrocarbons (PHC) from the bottom sediment samples of Nabil Bay are distributed very unevenly over the study area and their concentrations in samples varied widely from 0.66 to 21.7 mkg/g. The maximum estimates were observed at stations 2, 9, 3 (21.7-11.2 mkg/g), minimum at stations 1 and 6 (0.66-1.97 mkg/g). The definite regularities for the petroleum products distribution in bottom sediments were not found. The analysis of results of the quality control has shown that % of the duplicate divergence and % of the extraction of ersatz standard did not exceed the tolerance criteria of quality.

5.5. Microbiological researches in the Nabil Bay

When studying a structure of the water microbe cenosis in the Nabil Bay in September 1998, a total of 3 water samples were collected (conditionally named stations 1, 2, 3). Numbers of the following physiological groups of aerobic heterotrophic colony-forming microorganisms were determined in water: saprophyte heterotrophic bacteria, growing on RPA, marine heterotrophic organisms, developing under the different water salinity (habitat of Yoshimitsu- Kimura); petroleum-oxidizing, phenol-resistant, and metal-resistant; destructors of biopolymers of amylolytic, proteolytic, and lipolytic bacteria. A content of saprophyte heterotrophic bacteria in the examined water samples from the Nabil Bay stations in 1998 was 105 cell/ml. A number of marine heterotrophic bacteria adapted to the salinity gradient was 106 – 107 cell/ml. Indices of petroleum-oxidizing microorganisms in three samples constituted 103 cell/ml, 106 and 107 cell/ml; a number of phenol-resistant microorganisms ranged within 102 - 104 cell/ml (Table. 5.5.1). A proportion of proteolytic microorganisms in water samples was different. In one cases it constituted 3.2-4.3 %, in other cases 23.4 %. A significant part of heterotrophic community was formed by lipolytic microorganisms; in two water samples their proportions were 20,8 and 33,3 % (Table 5.5.2).

168 Table 5.5.1 Indices of numbers of the physiological groups from the aerobic saprotrophic microorganism community in seawater of the Nabil Bay studied stations in 1998, (cell/ml) Physiological groups of st.1 st. 2 st.3 microorganisms Marine saprotrophic 106 106 107 organisms Heterotrophic organisms –* 105 105 Phenol destructors 104 104 102 Petroleum destructors 103 106 107 *(–)- indefinite

Table 5.5.2 Relative numbers of some physiological groups from the aerobic saprotrophic microorganism community in seawater from the Nabil Bay stations (% of the total number of heterotrophic organisms) Physiological groups of st. 1 st. 2 st.3 microorganisms Heterotrophic 100 100 100 Proteolytic 23.4 3,2 4,3 Lipolytic 20,8 33,3 0,56 Cd-resistant 0 0 0 Pb- resistant 6,5 45,9 0,03 Co- resistant –* 0** 0 Cu- resistant – 1,74 0,42 Ni- resistant 5,7 15,5 0,08 Zn- resistant 0 0,12 0 Fe- resistant 10,8 36,5 1,3 *(–) - indefinite **(0) – absence of growth

Cd- and Co-resistant microorganisms were not found in the examined water samples of the bay. Zn- resistant microorganisms were found only in one water sample. The content of Ni- resistant forms varied from 0.08 to 15.5 %. The high indices of numbers were from individual samples of Pb- and Fe- resistant microorganisms; this reflects the geochemical peculiarities of the region (Table 5.5.2).

5.6. Phytoplankton of the Nabil Bay

5.6.1. Description of phytoplankton by the archive and literary data In July 1999, a total of 126 species and intraspecific taxons belonging to 6 microalgal divisions were found in the Nabil Bay. Diatom algae Bacillariophyta were the most diverse: 94 species and intraspecific taxons (75 % of the total number of algae). The genus Navicula (21 species) was the richest by species of diatom algae. Species from the genera Cocconeis (100 % of frequency), Navicula pupula var. rostrata (100 %), Eutreptia globulifera (89 %) were the most frequent. Cell densities varied within 233,31–2097,484 thousand cell/l, averaged 694,314 thousand cell/l, biomass 119,83-1084,05 mg/m3, averaged 453,76 mg/m3. The dominants were algae: of euglenic - Eutreptia globulifera (20-28 % of the total abundance, 37-50 % of the total biomass); of cryptomonades – species from genera Сhroomonas (cell density – 27 %, biomass - 21-50 %) and Plagioselmis (cell density - 42-55 %, 169 biomass – 32-36 %); of green by density - Thalassomonas sp. (42-55 %) (unpublished data of I.V. Motylkova, T.A. Mogilnikova, 2000).

5.6.2. Characteristic of phytoplankton in 2002 By the results of survey in September 2002, a total of 142 species and intraspecific taxons belonging to 7 microalgal divisions were found in the Nabil Bay. The most diverse were diatom algae Bacillariophyta – 106 species and intraspecific taxons (75 % of the total number of species). The rest algae divisions were represented by small numbers of species (from 2 to 11): dinoflagellates Dinophyta (8 %), green Chlorophyta (7 %), bluegreen Cyanophyta (5 %), cryptophytes Cryptophyta (3 %), chrysophytes Chrysophyta (1 %), euglenic Euglenophyta (1 %) (Appendix 2.6.1). Of diatoms, the genera Nitzschia – 13 species, Navicula – 10, Thalassiosira - 7, Melosira and Gomphonema– by 6 were the richest by species (Appendix 2.6.1). The most frequent were Cocconeis scutellum Ehr. (100 % of frequency), Plagioselmis punctata Butch. (86 %), Gomphonema angustatum (Ktz.) Rabh. (79 %). Species numbers at stations varied within 12-42. The greatest species diversity was recorded at station 1 (depth 7 m). Station 8 was characterized by the minimum species composition, where the number of species was 12. Ecological characteristic was determined for 23 species; among them, neritic species prevailed (96 %), a proportion of pantalass species was 4 %. The ecological-geographic characteristic for the rest found species was doubtful or unknown. The analysis and ratio of species representing different types of areas are given for 28 species. In the study region a total of 7 groups of species with the similar type of the area were found; among them, cosmopolites making up 40 % of the total number of species with the known belonging to the area type were the dominants. Boreal species (21 %) constituted a significant proportion. A species composition was formed by freshwater (40 %) and freshwater- brackish (26 %) species. On the major part of this area the quantitative phytoplankton indices were insignificant, their mean estimates were 178,46 mg/m3 by biomass and 129,496 thousand cell/l by abundance, without taking into account stations 4 and 9, which appeared to be exception (Appendix 2.6.1). A spatial distribution of the total biomass and abundance was extremely uneven (Appendix 2.6.2). Biomass varied within 4,42-3292,21 mg/m3, abundance 8,306-3074,556 thousand cell/l. Quantitative characteristics reached the maximum estimates at the shallow station 4 located in the near-mouth part of rivers: biomass 3,18 g/m3, abundance 1,021 million cell/l, respectively. This is caused by the great vegetation of the neritic euryhaline dinoflagellate Heterocapsa triquetra (Ehr.) Stein (3,17 g/m3 and 1,01 million cell/l; 96 % of the total biomass, 33 % of the total abundance) and freshwater bluegreen Oscillatoria sp. (1,87 million cell/l; 61 % of the total abundance) in this region. Besides, a high abundance was recorded in the surface layer at station 9 due to the development of small bluegreen Gomphosphaeria aponina Kutz. (1,311 million cell/l; 56 %). The minimum estimates of phytoplankton indices were recorded at station 8 (a site with the lowest salinity (2,4 ‰)): biomass constituted 4,42 g/m3, abundance 8,306 thousand cell/l. The abundance of dominants and subdominants was formed by diatoms: marine euryhaline Cocconeis scutellum (20-48 % of the total abundance), freshwater-brackish Rhoicosphaenia curvata (32-34 %); by cryptophytes: freshwater and, evidently, brackish-marine Plagioselmis punctata (23-25 %) at station 1. Several diatom species dominated by biomass: euryhaline Cocconeis scutellum (20-57 % of the total biomass), marine Thalassiosira pacifica (21-41 %), Cerataulina pelagica (54-55 %), Epithemia zebra var. рorcellus (24-25 %), and dinoflagellate Heterocapsa triquetra (26-96 %). Thus, the base of phytoplankton community in the strait was formed by species from the neritic complex. A total of 7 groups of species with the similar type of area were found; of them, widely distributed species (cosmopolites and boreal) prevailed. 170 A species composition was formed by freshwater and freshwater-brackish species. The mean biomass estimate was 178,46 mg/m3, abundance 129,496 thousand cell/l, without taking into account stations 4 and 9, where the maximum estimates of quantitative characteristics were recorded (one-two orders of magnitude higher than at other stations). Diatom and cryptophyte algae contributed most of all to the abundance formation. Diatoms dominated by biomass almost all over the area. Several species-dominants were found in the study region: by abundance - Cocconeis scutellum, Rhoicosphaenia curvata, Plagioselmis punctata, by biomass - Cocconeis scutellum, Thalassiosira pacifica, Heterocapsa triquetra.

5.7. Zooplankton of the Nabil Bay

5.7.1. Description of zooplankton by the archive and literary data By the data of the ECS and SakhNIRO joint surveys in 1999, a total of 28 species belonging to 11 taxonomic groups were found at 6 stations of the Nabil Bay during zooplankton studies. Copepods prevailed in species composition; they constituted 50 % of the total number of species. Representatives of this zooplankton group were found at all the surveyed stations. Amphipods from the Nabil Bay were presented by 4 species, other groups of plankton organisms constituted by 1 species or form. The mean biomass of plankton organisms in the Nabil Bay was 313 mg/m3. The maximum plankton biomass (909 mg/m3) was recorded at station 19 in the bay channel, minimum (37.6 mg/m3) at station 7 in the southern part of the bay. The base of zooplankton biomass was formed by the copepod Sinocalanus tenellus and adult and juvenile copepods from the genus Eurytemora. The mean abundance of plankton organisms in the Nabil Bay was 15749 ind./m3. The maximum zooplankton abundance (49555 ind./m3) was recorded at station 16 on the fairway round Zalesenniy Island, minimum (650 ind./m3) at station 7 in the southern part of the bay. Regarding to abundance, a domination of juvenile copepods from the genus Eurytemora and copepod Sinocalanus tenellus was recorded in samples. In general, a clear tendency of increase in zooplankton species composition and indices of abundance when approaching to the bay channel was watched in the area distribution of plankton organisms in the Nabil Bay (Ecological studies…, 2001).

5.7.2. Characteristic of zooplankton in 2002 Zooplankton was unevenly distributed over the bay area. This is connected with some factors: a level of mineralization and water temperature, affect of river, brook and tide run-off, uneven bottom relief, vegetation development. Three complexes form the bay zooplankton (Fig. 5.7.1). A total of 15 species and forms of organisms belonging to 3 taxonomic groups were found in samples (Table 5.7.1); of them, copepods were the most diverse (12 forms). High numbers of the near-bottom forms were recorded in samples due to the relatively small depth of the bay. 171

Fig. 5.7.1. Distribution of zooplankton complexes in the Nabil Bay in 2002

172 Table 5.7.1 A list of organisms from the Nabil Bay in 2002 № Group Form 1 Notholca acuminata Rotatoria 2 Synchaeta sp. 3 Polychaeta Polychaeta indet., larvae 4 Sinocalanus tenellus 5 Neocalanus plumchrus 6 Pseudocalanus newmani 7 Schmackeria inopina 8 Eurytemora asymmetrica 9 Eurytemora herdmani Copepoda 10 Acartia longiremis 11 Acartia hudsonica 12 Halicyclops sp. 13 Oithona similis 14 Harpacticoidae indet. 15 Nauplii copepoda

Major species were related to brackish and euryhaline. Numbers of zooplankters (Table 5.7.2) in the bay varied within 2425,0–50300,8 ind./m3, biomass 38,53–831,21 mg/m3, averaged 303,72 mg/m3. The third complex constituted the biomass maximum. Eurytemora herdmani made up the greatest biomass, and nauplii Eurytemora and other copepod species made up the greatest abundance.

Table 5.7.2 Zooplankton abundance and biomass by stations № st. Nb1 Nb2 Nb3 Nb4 Nb5 Nb6 Nb7 Nb8 Nb9 N, ind./m3 31735,6 7859,5 2425,0 2700,0 7450,0 12771,7 28490,7 3925,0 50300,8 B, mg/m3 576,83 209,46 38,53 59,20 182,43 89,21 831,21 41,68 705,00

5.8. Benthos of the Nabil Bay

5.8.1. General characteristics of benthos Benthos surveys in the Nabil Bay were carried out by the complex expedition of SakhNIRO and ECS in June 1999 in the northern part of the bay being influenced by the tide processes (Ecological studies…, 2001). However, due to the incorrect description, given by the authors of this report (for example, three benthos communities, in each of them the sea grass and bivalve Macoma balthica dominated by biomass), we were compelled to make our own description based on the primary materials of processing the benthos samples collected in 1999. A total of 54 species and forms of benthos organisms were found in the bottom biota composition of Nabil Bay by the results of a dredged survey (Appendix 5.8.1). Polychaetes (18 species), amphipods (9 species), and bivalves (6 species) formed the base of species composition. Bivalves Macoma baltica (41,8 % of the total biomass) and sea grass Zostera asiatica (23,5 %), Z. nana (9,4 %), Z. marina (7,7 %) were the key species (Table 5.8.1). The mean abundance of organisms over the bay area was 1360 ind./m2. Bivalves (444 ind./m2; 33 % of the total abundance) and amphipods (242 ind./m2; 18 %) constituted the maximum numbers; gastropods (191 ind./m2; 14 %) and polychaetes (173 ind./m2; 13 %) were also mass groups (Fig. 5.8.1).

173 Table 5.8.1 Averaged quantitative characteristics of benthos groups from the Nabil Bay Group Species numbers N, ind./m2 В, g/m2 Biomass, % Algae 1 0.0 25.208 4.6 Magnoliophyta 3 4.4 220.153 40.5 Coelenterata 1 4.4 1.538 0.3 Nematodes 1 1.5 0.003 0.0 Nemertini 1 0.9 0.003 0.0 Polychaeta 18 172.7 5.295 1.0 Oligochaeta 1 107.0 0.101 0.0 Hirudinea 1 0.4 0.001 0.0 Sipuncula 1 4.9 0.038 0.0 Gastropoda 3 190.6 5.096 0.9 Bivalvia 6 443.7 270.864 49.9 Mysidae 1 113.9 2.425 0.4 Cumacea 1 7.5 0.013 0.0 Amphipoda 9 242.4 1.402 0.3 Isopoda 3 45.9 7.159 1.3 Decapoda 2 7.2 3.551 0.7 Insecta 1 13.5 0.138 0.0 Total 54 1360.9+63 543+34 100.0

2% 8% 3% 1% 33% 8%

13%

14% 18%

Bivalvia Amphipoda Gastropoda Polychaeta Mysidae Oligochaeta Isopoda Insecta Прочие

Fig. 5.8.1. Ratio of numbers of the main benthos groups from the Nabil Bay in 1999

A density of colonies of the Nabil Bay bottom organisms was heterogeneous (Fig. 5.8.2). In the region of channel, the sites of the higher density of organisms were timed, mainly, to the sand-silt grounds at st. №№ 17 and 34 (5900 ing./m2 and 3120 ind./m2, respectively). On the basic area the highest abundance indices were recorded in the basin (st. 11 – 2270 ind./m2). On the rest part of the open area the number of bottom organisms did not exceed 900 ind./m2. 174

51.75

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16 4000 15

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3000 11 10 9

2500 51.6

2000

1500 51.55 1000

500

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51.45 143.25 143.3 143.35 143.4 Fig. 5.8.2. Distribution of bottom hydrobiont numbers (ind./m2) in the Nabil Bay in 1999 (decimal coordinates)

The mean biomass of the bay bottom organisms was 540 g/m2. Bivalves (270 g/m2; 49,9 % of the total biomass) and sea grass (220 g/m2; 40,5 %) made a maximum contribution to the total biomass (Fig. 5.8.3).

1% 1% 1% 5% 1% 1%

49% 41%

Bivalvia Magnoliophyta Algae Isopoda Polychaeta Gastropoda Decapoda Прочие

Fig. 5.8.3. Ratio of biomasses of the main benthos groups from Nabil Bay in 1999 175

A distribution of biomass of the bottom organisms in the Nabil Bay was heterogeneous too and, in general, repeated the abundance distribution (Fig. 5.8.4). In the region of channel, sites with the higher biomass were timed, mainly, to the sand-silt grounds at stations 17 and 34 (2262 g/m2 and 1907 g/m2, respectively). On the basic area the highest biomass indices were recorded in the basin (st. 11 – 394 g/m2). On the rest part of the open area the biomass of bottom organisms did not exceed 140 g/m2.

51.75

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51.7 2829 1724252730

16 2000 15

51.65 14

1500 11 10 9

51.6 1000

500

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200

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51.45 143.25 143.3 143.35 143.4 Fig. 5.8.4. Distribution of benthos biomass (g/m2) in the Nabil Bay in 1999 (decimal coordinates)

5.8.2. Benthos communities When distinguishing the communities based on the clasterization of data by the Shoener’s index, a dendrogram on the similarity of dredged stations in the Nabil Bay was built (Fig. 5.8.5). The dendrogram shows 2 types of communities, which are well harmonized with a hydrological description of the bay (see above) under the map image (Fig. 5.8.6) Community Macoma balthica + Zostera var., which existence is determined by the directly lagoon brackish waters occupies the basic area of the bay.

176

Fig. 5.8.5. Dendrogram of similarity of the dredged stations in Nabil Bay in 1999 by the Shoener’s index

51.75

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51.7 2829 1724252730

16

15

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11 10 9

51.6

51.55 Условные обозначения: - Сообщество Macoma balthica+Zostera var. 51.5 - Сообщество Zostera var.

51.45 143.25 143.3 143.35 143.4 Fig. 5.8.6. Main benthos communities of the Nabil Bay in 1999

177 Community Macoma balthica + Zostera var. A described community was observed practically over all the area of Nabil Bay at depths of 0,5-4 m on the loam – fine sand grounds under the near-bottom water salinity 9,3-27,5 ‰ at stations №№ 10, 11, 14, 17, 25, 27, 30, and 34 during the survey. Polychaetes (14 species of 44) formed the base of species composition; bivalves and sea grass ((60,9 % and 30,3 % of the total biomass, respectively) formed the main biomass of the community. In general, the quantitative indices constituted 1850 ind./m2 and 796 g/m2 (Table 5.8.2).

Table 5.8.2 Ratio of benthos groups in the community Macoma balthica + Zostera var. Group Species numbers N, ind./m2 В, g/m2 Biomass, % Sipuncula 1 7.4 0.065 0.0 Polychaeta 14 287.6 8.523 1.1 Oligochaeta 1 166.1 0.157 0.0 Nemertini 1 1.7 0.005 0.0 Nematodes 1 2.8 0.006 0.0 Mysidae 1 0.8 0.273 0.0 Magnoliophyta 1 0.0 241.094 30.3 Isopoda 2 23.2 0.474 0.1 Insecta 1 3.3 0.050 0.0 Gastropoda 3 257.4 5.020 0.6 Decapoda 1 8.1 3.936 0.5 Cumacea 1 14.0 0.024 0.0 Coelenterata 1 8.3 2.883 0.4 Bivalvia 6 762.3 484.623 60.9 Amphipoda 8 303.7 1.765 0.2 Algae 1 0.0 46.875 5.9 Total 44 1847.0 795.774 100.0

Bivalves Macoma balthica (Linne) (656 ind./m2; 419 g/m2; 52,6 % of the total biomass) and sea grass from the genus Zostera (241 g/m2; 30,3 %) dominated in the community. Bivalves Liocyma fluctuosa (Gould, 1841) and filamentous algae Chaetomorpha sp. (12,6 % of the total biomass) contributed greatly into the formation of total biomass too. Other species did not play a significant part in the community (4,5 % of the total biomass). A community with the dominant of sea grass from the genus Zostera was observed near the channel inflow to the basic area of the bay.

Community Zostera var. A described community was observed at depths of 0,2-4,5 m on the grounds from loam to medium sand under the near-bottom water salinity 9,9-26,2 ‰ at stations №№ 9, 16, 24, 28 during the survey. Polychaetes (8 species of 26) formed the base of species composition; sea grass (79,5 % of the total biomass) formed the main biomass of the community. In general, the quantitative indices constituted 693 ind./m2 and 430 g/m2 (Table 5.8.3). Sea grass Zostera var. (342 g/m2; 79,5 % of the total biomass) dominated in the community. Isopods Saduria entomon (Linne) and L. fluctuosa, and M. balthica (summarized contribution 15 % of the total biomass) contributed greatly into the formation of total biomass too. Other species did not play a significant part in the community (5,5 % of the total biomass). 178 Table 5.8.3 Ratio of benthos groups in the community Zostera var. Group Species numbers N, ind./m2 В, g/m2 Biomass, % Sipuncula 1 3.3 0.013 0.0 Polychaeta 8 64.0 2.792 0.6 Oligochaeta 1 49.5 0.043 0.0 Mysidae 1 20.0 0.467 0.1 Magnoliophyta 1 0.0 341.667 79.5 Isopoda 2 124.9 25.891 6.0 Insecta 1 20.4 0.177 0.0 Gastropoda 1 3.9 6.031 1.4 Decapoda 2 10.0 5.367 1.2 Bivalvia 4 138.2 46.094 10.7 Amphipoda 4 258.6 1.379 0.3 Total 26 692.9 429.921 100.0

Benthos of the Aslanbekov Strait A detail description of bottom inhabitants of the near-mouth part of Aslanbekov Strait joining the Nabil Bay with a sea was given by V.D. Tabunkov and co-authors (Tabunkov et al., 1988) by the data of the complex expedition of Zoological Institute of AS USSR in July-August 1978 at R/V “Poseidon”. A strait littoral is practically lifeless. Inhabitants of southern (steep) and northern (flat) shores differ strongly (Tabunkov et al., 1988). Biocenosis Macoma calcarea was located near the southern shore of the strait at the depth up to 2 m on sandy grounds (Fig. 5.8.7). This biocenosis was poor by composition and included only 5 species (Table 5.8.4). A single species of infauna (M. calcarea) prevailed by biomass. Ischyrocerus engimaticus was the most abundant. Detritophagans formed a base of the biocenosis trophic structure (Fig. 5.8.7, Table 5.8.4).

Table 5.8.4 Composition of biocenosis Macoma calcarea Species Group N, ind./m2 В, g/m2 Infauna Macoma calcarea Bivalvia 40 4.34 Epifauna Ischyrocerus engimaticus Amphipoda 40 0.36 I. elongaticus Amphipoda 20 0.2 Isopoda (2 species) Isopoda 40 0.08

179

Fig. 5.8.7. Vertical distribution of bottom communities in the near-mouth part of Aslanbekov Strait (Nabil Bay) (in: Tabunkov et al., 1988). Indications: 1 – Zostera marina, 2 – Edwardsia sp., 3 – Nephtys ciliata, 4 – Cryptonatica sp., 5 – Macoma calcarea, 6 – Liocyma fluctuosa, 7 – Mytilus trossulus, 8 – sand, 9 – silty sand; trophic groups: 10 – sestonophagans and filtrators, 11 – autotrophic, 12 – detritophagans, 13 – predators; communities: I - Macoma calcarea + Zostera marina; II - Macoma calcarea; III - Liocyma fluctuosa + Mytilus trossulus + Macoma calcarea; IV - Edwardsia sp. + Nephtys ciliata + Liocyma fluctuosa + Cryptonatica sp. Numerals on the left of a thick vertical line indicate a depth (m). Histograms indicate proportions for each of trophic groups of the total community biomass (given above the histograms).

Biocenosis Macoma calcarea + Zostera marina was distributed on the northern side of the strait on sandy-silt grounds. Bivalves M. calcarea made up the most abundance and biomass there (Table 5.8.5). Sea grass Z. marina was a sub-dominant species. Bivalves L. fluctuosa, hydroid polyps Lafoenia maxima and gastropod Littorina kurila played a significant part in formation of the total biomass too. As in the first biocenosis, a base of the trophic structure was formed by detritophagans (79 % of the total biomass).

Table 5.8.5 Composition of biocenosis Macoma calcarea + Zostera marina Species Group N, ind./m2 В, g/m2 Plants Zostera marina Magnoliophyta 302 Phytofauna Littorina kurila Gastropoda 30 1.39 Laying of Gastropoda 1.452 Epifauna Lafoenia maxima Hydroidea 1.92 Mytilus edulis Bivalvia 25 0.177 Holothurioidea Holothurioidea 1 0.17 Tiron acanthurus Amphipoda 10 0.13 Isopoda (3 species) Isopoda 17 0.074 Gammariae(2 species) Amphipoda 6 0.047

180 Table 5.8.5 (continued) Species Group N, ind./m2 В, g/m2 Ischyrocerus sp. Amphipoda 1 0.001 Infauna Macoma calcarea Bivalvia 2560 1653.4 Liocyma fluctuosa Bivalvia 120 135.2 Echiuridae Echiurida 10 2.72 Harmothoe imbricata Polychaeta 10 0.55 Glyceridae Polychaeta 10 0.12 Total 2800 2099,351

Biocenosis Liocyma fluctuosa + Mytilus edulis + Macoma calcarea was observed at the depth of 2-5 m from the both sides of the strait. A total of 17 zoobenthos species entered the biocenosis composition. Among bivalve dominants, L. fluctuosa was the most significant (Table 5.8.6). In addition, the epifauna species Saduria entomon and Balanus sp.were important too. Infauna formed the main proportion of biocenosis biomass (78 %). A proportion of sestonophagans and filtrators constituted 80 %, and detritophagans 19,8 % in the trophic structure of biocenosis.

Table 5.8.6 Composition of biocenosis Liocyma fluctuosa + Mytilus edulis + Macoma calcarea Species Group N, ind./m2 В, g/m2 Epifauna M. edulis Bivalvia 20 111,6 S. entomon Isopoda 4 14,4 Balanus sp. Cirripedia 8 3,864 Hydrozoa Hydrozoa 8 0.2 Ischyrocerus indet. (2 Amphipoda 32 0.044 species) I. elongatus Amphipoda 24 0.04 I. krascheninnikovi Amphipoda 4 0.016 Isopoda indet. Isopoda 4 0.012 Infauna L. fluctuosa Bivalvia 832 351.84 M. calcarea Bivalvia 320 101.6 Criptonatica sp. Gastropoda 4 0.96 Goniada maculata Popychaeta 12 0.68 Nereis vexillosa Polychaeta 4 0.416 Ophelia limacina Polychaeta 4 0.1 Chone teres Polychaeta 4 0.06 Astarte sp. Bivalvia 4 0.024 Total 1288 585,856

An indivisible polymixed biocenosis Edwardsia sp. + Nephthys ciliata + Liocyma fluctuosa + Nemertini + Criptonatica sp.was observed at the depth more than 5 m. Bottom inhabitants are represented, exclusively, by the infauna organisms. A total number of species was 9, due to disappearing the epifauna organisms from its composition. Polychaetes constituted the greatest number of species (5); of them, only Nephthys ciliata formed a high biomass (Table 5.8.7). A trophic group of dead-eater – predators dominated by biomass (77 %). 181 Table 5.8.7 Composition of biocenosis Edwardsia sp. + N. ciliata + L. fluctuosa + Nemertini + Cryptonatica sp. Species Group N, ind./m2 В, g/m2 Edwardsia sp. Actiniaria 10 8.315 Nephthys ciliata Polychaeta 5 5.25 L. fluctuosa Bivalvia 25 3.5 Nemertini Nemertini 25 3.43 Cryptonatica sp. Gastropoda 21 3.1 Pectinaria brevicoma Polychaeta 5 1.8 Spio sp. Polychaeta 20 0.45 Ch. teres Polychaeta 5 0.18 Glicera capitata Polychaeta 5 0.16 Total 121 26,185

Analysis of composition and structure of the Aslanbekov Strait bottom biota at the near- mouth site proves a zone distribution of biocenoses. With increase in depth, as a rule, a biomass of biocenoses declines and their trophic structure changes along with the change in a qualitative composition (Tabunkov et al., 1988).

5.9. Ichthyofauna of the Nabil Bay

The SakhNIRO specialized and complex expeditions were not conducted in the Nabil Bay. Data on the bay ichthyofauna (Table 5.9.1) are given by the episodic observations and literary information (Tabunkov et al., 1988; Gritzenko, 1990, 2002; Safronov et al., 2003).

Table 5.9.1 A list of fish and fish-like species of the Nabil Bay Families Species and subspecies Petromyzontidae Lethenteron japonicum – arctic lamprey **Clupea pallasii – herring Clupeidae ****Sardinops sagax melanosticta – west Pacific sardine Oncorhynchus gorbuscha – pink salmon Oncorhynchus keta – chum salmon Oncorhynchus masou – masu salmon Salmonidae Oncorhynchus kisutch – coho salmon ***Salvelinus leucomaenis – Sakhalin char *** Salvelinus malma krascheninnikovi – southern malma *Parahucho perryi – Sakhalin taimen Coregonidae Coregonus ussuriensis – Ussuri whitefish H. nipponensis – wakasagi Osmeridae H. olidus – pond smelt Osmerus mordax – Asiatic smelt ***Tribolodon brandtii – eastern redfin Cyprinidae ***Tribolodon ezoe – Pacific redfin ***Tribolodon hakuensis – big-scaled redfin Balitoridae Barbatula toni – Siberian stone loach Gadidae **Eleginus gracilis – saffron cod Gasterosteus aculeatus – threespine stickleback Gasterosteidae Pungitius pungitius – ninespine stickleback Pungitius sinensis – Amur stickleback 182 Families Species and subspecies Zoarcidae Zoarces elongates – Pacific eelpout Cottidae Megalocottus platycephalus – flathead sculpin ***Platichthys stellatus – starry flounder Pleuronectidae Liopsetta pinnifasciata – banded flounder * Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the last years

Such anadromous fishes as arctic lamprey and southern malma migrate from a sea to river mouths through the bay along its main fairway from north to south. Sakhalin taimen, Sakhalin char, smelts Osmeridae, Pacific redfins Tribolodon, and sticklebacks Gasterosteidae inhabit the bay round the year and episodically move out to the open part of the sea. They migrate for spawning both from the open part of the sea and from the bay. Juveniles of arctic lamprey, Pacific salmon, and southern malma migrate to the sea, not staying in the bay for a long time. Juveniles of Sakhalin char, Sakhalin taimen, Pacific redfins, sticklebacks, and larval smelt stay to live in the bay. During a year, they more than once move out to the sea. All the life cycle of these species is being passes by interchanging the bay habitat with the open part of the sea. Some part of Asiatic smelt larvae occur in the open part of the sea immediately after the migration from rivers. There is an impression that numbers of some anadromous species (Sakhalin taimen, Pacific redfins) in the period of feeding are greater in the bay compared to those being spawned in the rivers of its basin. Evidently, fishes from other regions of reproduction periodically feed in the Nabil Bay. Freshwater species (Siberian stone loach) occurred in the southern, the most freshened part of the bay. There, the greatest densities of aggregations of the juvenile Pacific redfins and sticklebacks (including Amur stickleback inhabiting only fresh and brackish waters) were found. A wide and deep fairway passes in the bay from the strait, joining it with the sea, from north to south along the eastern shore. At this very site, marine species (saffron cod, flounders Pleuronectidae, sculpins Cottidae, eelpout and others) move far into the bay. Some marine species (flathead sculpin, banded flounder) occur in the bay during the major part of their life. Juvenile starry flounder, which is common all over the bay area, inhabit the bay up to the period of its maturation. There is a fishery in the bay: in summer – Pacific salmon (pink and chum), in winter – saffron cod. Three patrimonial communities are located on the shore of this water body: «Limanzo», «Ungir», «Koivongun». A total of 15 persons live there.

5.9.1. Main commercial species Of Pacific salmon, pink, chum, coho, and masu enter the rivers flowing into the Nabil Bay for spawning. Pink and chum salmon are commercially important. Pink salmon is the main commercial species. A total area of salmon spawning grounds in rivers flowing into the Nabil Bay makes up 576100 m2 (Table 5.9.2) (Report…, 1957). Pink salmon This species is the most abundant of Pacific salmon in odd years. Under the mean annual density of 140 ind./100 m2, during filling the spawning grounds with pink spawners, about 806,5 thousand fish pass through the Nabil Bay in the period of its anadromous migration. At the mean long-term weight of 1,22 kg for one individual, its annual biomass may constitute 984,0 t. In odd years, 8,3 million pink fry migrate to the sea for feeding through the bay area; in even years - 41,9 million fry.

183 Table 5.9.2 Rivers and their spawning grounds in the basin of Nabil Bay River Length, km Water area, km 2 Spawning area, m2 Species of Pacific salmon Nabil 101 1010 372000 pink, chum, coho Orkunyi 40 132 20000 pink, chum Vazi 42 326 19500 pink, chum

Chum salmon Chum salmon is not a dominant by abundance in the Nabil Bay. Its commercial fishing is realized only in individual years in the mouth of Nabil River. A period of the spawning run in the Nabil River is shorter than in the Tym River. The beginning of the anadromous migration and main run are noted in dates close to those in the Tym River. A period of fry migration downstream the Nabil River is very stretched. A full completion of its migration in rivers Tym and Nabil occurs almost in one and the same period (Gritzenko et al., 1978; Gritzenko, 1990, 2002).

Coho and masu salmon One of the most abundant in northeastern Sakhalin coho salmon population spawns in the Nabil River. Fish lengths varied from 52,0 to 82,0 cm, weight from 1,7 to 7,0 kg (Gritzenko, 2002). Masu salmon is not abundant. Fry are common in rivers flowing to the bay. Masu lengths in Nabil River varied from 43,0 to 62,0 cm, weight from 1,0 to 3,6 kg, age, as a rule, from 21+ to 32+. However, specimens at 42+ age were observed (Rukhlov et al., 1976). Females prevailed by numbers among anadromous fish (to 75,7 %). The same tendency was observed for downstream migrants. Dwarf males are common among juveniles (Gritzenko, 2002). Fishing sites exploited by the companies in the basin of Nabil Bay are presented in Table 5.9.3 (A list of fishing sites …, 1998).

Table 5.9.3 Fishing sites exploited by the companies in Nabil Bay № of Borders Extension, km User site 6,2 km south of M.Tamary – 6,0 km Privately owned 1 0,2 south of M.Tamary enterprise «Volodin» Patrimonial Cape Stariy Nabil – Chernaya River – 2 14 communities Cape Plushev «Koivongun» 2 km south of the northern extremity of 3 Aslanbekov Peninsula – northern 2 NSKH «Ungyr» extremity of Goreliy Island Cape Plushev – Pologiy Island – Chaika 4 6 NMP «Kaigan» Island – Cape Stariy Nabil Chernaya River – Cape Plushev – Fish collective farm 5 Pologiy Island – Cape Stariy Nabil – 50 «Vostok» Aslanbekov Strait

Saffron cod If at the beginning of the 1980s a number of settled gear did not exceed 110 units, then in the 1990s it decreased to 40-50. The proportion of the Nabil Bay is only from 0 to 25,0 % of the total catch of saffron cod in the region (see Fig. 7.9.6 in chapter 7). The mean length of saffron cod from catches varied from 20,7 cm in 2002 to 30,6 cm in 1993 (Fig. 5.9.1). 184

33 31

см 29 , 27 АС

25 длина

23 21 19 Средняя 17 15 1988 1990 1992 1994 1996 1998 2000 2002 Годы наблюдений

Fig. 5.9.1. Dynamics of the mean length of saffron cod (cm) in the Nabil Bay during 1988-2002 (except for 1992, 1997, 1998 and 2001)

By the early February, more than one third of fish, as a rule, have already been spawned. A great part of fish is in the process of spawning or in the pre-spawning state. Saffron cod consume small forms of crustaceans in this period; sometimes their own eggs occur in stomachs. A catch of saffron cod in the bay varied from 9 (2001) to 35 t (1989). A number of gear settled for fishery fluctuated from 24 (1997) to 57 units (1999, 2000).

Flathead sculpin A capture of “sculpin” in the Nabil Bay constituted from 10,9 to 24,8 % of the total catch over the region and fluctuated from 65 t (1992) to 234 t (1988), averaged 155 t. A percentage composition of “sculpin” in catches is given in Fig. 5.9.2.

Пол.камбала

Зубастая корюшка

Бельдюга

Пл.бычок

Навага

0204060

% состав "бычка"

Fig. 5.9.2. Species composition of “sculpin” in catches from the Nabil Bay (in %, by biomass) by the data of 1991 185

Thus, there is a fishing of Pacific salmon, saffron cod, and other species with the general name “sculpin” in the Nabil Bay in small numbers. Pacific salmon spawn in rivers flowing into the bay. Many anadromous fishes (Sakhalin taimen, Sakhalin char, Pacific redfins and others) including those from the other regions of reproduction feed in the bay during a year. Juvenile starry flounder being much abundant on the shelf of northeastern Sakhalin feed in the bay (as a rule, before the maturation process). 186 6. LUNSKY BAY

6.1. General physic-geographic characteristics of the Lunsky Bay

The Lunsky Bay fundamentally differs from the earlier studied bays of the north-east and, first of all, by its geographical location not far from the foot of East-Sakhalin Mountains. A vegetation of the bay shore is represented by the coniferous woods, in contrast to the tundra round the other bays. This is a shallow water body of the lagoon type, which consists of two parts. The spits, separating the bay from the Okhotsk Sea, are presented by terraces reaching 50 m in height. These accumulative forms are formed, mainly, by different-grained sand with prevailing the coarse- and medium-grained fractions. Both silicon and boron mineral waters and the Ufsky oil-gas field have been explored on the bay shore. A geologic construction of this region differs from other bays. The major area is occupied by the rocks which do not present in the water collection of other bays. This region is built by the rocks of the Quaternary, Paleogenic, Neogenic, and Mesozoic systems. A bottom of the bay and its shores are formed by the Quaternary rocks (predominantly of the low- and mid-quaternary links, in contrast to other bays, where the rock of the upper- Quaternary and modern links dominate) and a small area of rocks of Okobykaisky and Daginsky suites of the complex of Neogenic rocks, which dominate in the water collection of the other bays of northeastern Sakhalin. Rivers drain the territories, which are formed by the Quaternary rocks of the low- and mid-quaternary links, and rocks of the Uranaisky, Khuzinsky, and Barsky suites of the Miocene. A considered region is located in a zone of influence of the monsoon from the temperate latitudes; its peculiarity is a seasonal change in the dominating wind flows. A winter monsoon, occurring over the area of Okhotsk Sea from October through March, causes predomination of winds of the northern compass point in this region. A summer monsoon is observed from May-June to early September. During this period the winds of southeastern and southern directions prevail. The autumn- winter storms with their strong northeastern and eastern winds cause heavy raisings of the water level. As far as the Lunsky Bay is relatively deepwater, then in winter its major part is not frozen to the bottom. Ice thickness in the bays of northeastern Sakhalin reaches 1.4 m in the basin and 1 m in channels. North winds in this region cause raising in the water level – moving a surface water layer to a shore. South winds lead to lowering in the water level - moving a surface water layer from a shore, and also to the lifting of deep, cold, and salt waters to the surface (upwelling). A coastal zone of the Lunsky Bay is a peculiar region of summer upwelling. The maximum summarized current velocities (mainly, represented by tidal ones) opposite the Lunsky Bay make up about 70 cm/sec. In the considered region a constant character of circulation of the water masses (a constant northeastern current) is destabilized by the influence of tidal waves. Daily tides are marked there. A tide estimate near the Lunsky Bay reaches 1.4 m. A tidal wave, moving along the shore, creates an overfall of water level between a sea and a bay. Thus, a flow of seawater, directed inside the bay, appears. The ebb flow is approximately equal to the tide one. That is why, a shift of the inlet shore line in the Lunsky Bay is relatively balanced. A rough sea plays the essential part in destruction of the shore line of the inlet. Autumn raisings of the water level (September-October) are an important factor in the process of formation of the bay ecosystem. During several days seawater gradually flow into the bays due to the wind pressure. As far as this process is rather long, a significant volume of seawater enters the bays. After the wind stopping, the accumulated water mass moves to a sea, grasping solid materials. Some small rivers and many small brooks flow into the Lunsky Bay. A summarized water discharge makes up about 3 m3/sec. Due to this, the influence of freshwater run-off practically is 187 not felt (Latkovskaya et al., 2001). As it was mentioned above, tides influence upon the bay ecosystem most of all. Regarding to the type, it is a regular daily tide being characterized by one high and one low tide during the period round the moon (24 hours and 50 min.). The maximum depth recorded both on the bay fairway and at the inlet into the bay was 5 m. Depths along the fairway (tidal trays) of the bay constitute 2-5 m. In general, this water body is deeper than other bays of northeastern Sakhalin. A tidal current in the Okhotsk Sea moves from north to south at a distance of several kilometers from the shore line. A flow of seawater, moving inside the bay, arises only due to the overfall (gradient) of the water level between a sea and a bay (excluding a storm period). A flow velocity at the inlet to the bay, by our observations, is approximately 70-80 cm/sec. After entering the bay, seawater is distributed from the inlet by all directions and reaches all the points of the bay. The ebb current in the sea opposite the Lunsky Bay moves from south to north in several kilometers from the shore. Under the joining of the ebb flow from the bay with the sea ebb flow due to the turbulence, velocities of flows become even. That is why, the water velocity during the ebb, when moving out of the bay, corresponds the velocity of ebb moving to the sea (about 70 cm/sec). By the data of 2000, water salinity in the northern part of Lunsky Bay varies insignificantly: at the surface salinity varies from 23.2 to 27.4 ‰, near the bottom from 23.2 to 28.4 ‰. The maximum difference between surface and near-bottom salinity in this part of the bay was 2.1 (average 0.6±0.7 ‰). A significant gradient of this index under a small depth (1.1 m) was observed only in the region located near the codened of the Yuzhniy Lake: from 14.9 ‰ at the surface to 25 ‰ near the bottom; this is connected with the run-off influence of small brooks. In the southern part of the bay, a more complex picture was observed being caused by the large river run-off in this part. There the salinity at the surface varied from 1.6 to 25.8 ‰, near the bottom from 3.9 to 29.5 ‰. On average, a salinity gradient in this region of the bay constituted 3.4±4.9 ‰ (maximum 16.2 ‰). In the mouth regions a carrying out of river waters is watched. A picture of temperature and salinity distribution showed the occurrence of several types of waters on the bay area. Waters, which characteristics correspond to those in a sea, are related to commonly marine ones. This water mass is spatially located all the time at the inlet to the bay and during tides distributed along the fairways. The strongest influence was exerted by Okhotsk Sea waters upon the eastern region of the northern part of the bay, where the water temperature both at the surface and near the bottom did not exceed 10 °С. The second type in the bay is presented by the river carry-out. Their influence was watched only at the proper near-mouth sites, where the water temperature was not lower 14-16 С. The third type is so-called “proper flood water”; its temperature was within 10-14 °С. Spatially, this water mass is located in the central part of the bay. A proper flood water has some peculiarities: at several stations the near-bottom temperature was lower than in the Okhotsk Sea. An interesting region is distinguished at the outlet of thermal waters. There during the whole period of observations the water temperature did not decline lower than 22 °С. Daily observations for temperature, salinity, and suspended matters in water from 23.00 on 16 July through 23.00 on 17 July showed practically the absence of freshwater run-off in this part of the bay. At the same time, the water level was measured on the river. The change in water level during 24 hours reached 60 cm. Salinity varied from 28.73 ‰ to 29.83 ‰, temperature from 9.29 to 12.67 °С. Fluctuations in the content of suspended matters constituted 20.78-22.34 mg/l. The tide was being watched from 23.00 to 8-8.30 in the morning, when salinity increased, and water temperature practically did not change. The picture is more interesting during the ebb. First of all, a surface layer of the warmed, slightly freshened (only for 1 ‰), and turbid with the river run-off water begins to flow away. This water layer passes through the daily station during several hours. Further, a proper flood water moves; it corresponds to the sea water by salinity, but it is more cold and clear even compared to the sea at this moment. That is, flood water fixes the densest sea water, which appears in the bay during upwelling. Thus, the near- 188 bottom water is a characteristic of density extremes of the coastal waters appearing in the bay. This is clearly seen in the southern part of the bay; there the near-bottom temperature was 4 °С, whereas the temperature of seawater at the inlet to the bay was almost 11 °С. Thus, having analyzed the hydrologic data, one may conclude that the Lunsky Bay can be related to the commonly marine one. By hydrologic characteristics, two regions can be distinguished: northern and southern parts. A water salinity in the northern part of Lunsky Bay varies insignificantly. In the southern part a salinity gradient at the mouth sites of rivers is higher due to the river run-off. Three water masses simultaneously occur in the bay: commonly seawaters (during a tide in the regions, adjoining to the outlet, and fairways), transformed river run-off (at the near-mouth river sites), and proper water (spatially located in the bay basin). There is an interesting region, where due to the outlet of thermal waters, a site with the water temperature reaching 23 °С was formed, as well as the site with the coldest water in the southern end of the bay (Latkovskaya et al., 2000).

6.2. Hydrology and hydrochemistry of the Lunsky Bay

6.2.1. Results of hydrologic-hydrochemical researches by the archive and literary data Archive data on the Lunsky Bay are presented by the data of survey carried out by the scientific expedition of SakhNIRO in July 2000 (Latkovskaya et al., 2001). The data on hydrologic-hydrochemical regime, particle-size composition of bottom sediments, and a content of pollutants occurring in them are practically absent in literature. In July 2000, a total of 12 hydrochemical stations were performed; pH value was measured at 28 stations. Samples of bottom sediments for a particle-size composition and concentrations of pollutants were taken at 26 stations. Statistic parameters of hydrochemical indices of the Lunsky Bay water are given in Table - 6.2.1. Concentrations of N-NO2 were below a threshold of detectability of the method in all samples. At the surface pH values varied within 7.62 – 8.76, near the bottom 6.73 – 8.51. At 40 % of stations, pH values were the same at surface and near bottom. The maximum gradient of pH was recorded in the southern part of the bay. In general, pH value in the southern part was lower than in the northern part of the bay. 3 Contents of dissolved oxygen (О2) during the survey varied from 10.15 to 16.73 mg/dm . The maximum estimate of this parameter was recorded at a station located near the thermal sources. The minimum concentrations of О2 were observed at a station located in the center of a zone of the slimy matters’ accumulation. A biochemical oxygen demand for 5 days (BOD5) in the Lunsky Bay water varied from 3 3 1.49 to 12.59 mgO2/dm , averaged 4.66 mg O2/dm . A clear anomaly was observed in the region of outlet of the thermal waters, where the estimates of this index were maximum.

Table 6.2.1 Statistic parameters of hydrochemical indices of the Lunsky Bay water in July 2000 Index Хav. σ Min Max Сv, % рН 8.20 0.21 7.62 8.76 2.62 Dissolved oxygen, 13.04 2.49 10.15 16.73 19.1 mg/dm3 3 BOD5, mg/dm 4.66 3.59 1.49 12.58 77.0 Suspended matter, 15.33 15.02 4.20 56.20 98.0 mg/dm3 Chlorophyll a, mkg/dm3 2.93 2.52 0.39 7.08 85.9 Pigm.index 2.70 1.07 1.78 5.00 39.5 189 Nitrogen ammonium, 54 39 16 135 93.6 mkg/dm3 Nitrogen nitrate, 15.73 8.60 5.29 38.77 72.8 mkg/dm3 Silicon, mkg/dm3 792 926 163 2700 54.7 Phosphorus mineral, 21.6 13.6 3.0 41.5 116.9 mkg/dm3 Рhosphorus general, 31.8 15.3 13.8 56.2 62.7 mkg/dm3 Рhosphorus organic, 9.7 5.8 1.8 22.0 48.3 mkg/dm3 Petroleum hydrocarbons, 0.22 0.20 0.00 0.61 59.7 mg/dm3

Concentrations of general phosphorus (dissolved and suspended) varied within 13.80 – 56.20 mkg/dm3, averaged 31.75 mkg/dm3. The major part of phosphorus in the Lunsky Bay water was presented by the mineral form as orthophosphates (70 % of the total phosphorus). Concentrations of silicon in the Lunsky Bay water varied from 163 to 2700 mkg/dm3, averaged 792 mkg/dm3. The maximum estimates were recorded at stations located in the river mouths. The minimum estimates were recorded at stations not exposed to the influence of river water. A content of suspended matters varied from 4.20 to 56.20 mg/dm3, averaged 15.33 mg/dm3. Maximum estimates were recorded at the mouth sites of the rivers and timed to the regions with the smaller depths and great content of thin fractions of the sediments. Minimum estimates were observed at stations during the tide, and at great depths. Concentrations of chlorophyll a varied from 0.39 to 7.08 mg/dm3, averaged 2.93 mg/dm3. The maximum estimate was recorded at a station located at the inlet to Yuzhnoye Lake, minimum - in the southern part of the bay.

6.2.2. Results of hydrologic-hydrochemical researches in 2002 Results of hydrologic-hydrochemical analysis of samples from the Lunsky Bay are given in Appendix 6.2.1. Some statistic characteristics of the determined parameters are reflected in Table 6.2.2.

Table 6.2.2 Some statistic characteristics of the determined parameters from the Lunsky Bay in 2002 Ingredients Xav Xmax Xmin Depth, m * 3.0 0.4 Temperature, 0 С 12.0 13.6 9.7 Salinity, ‰ 20.0 29.7 4.1 pH value 8.59 9.05 8.00 Dissolved oxygen, mg/dm3 10.52 12.40 8.63 Nitrogen nitrite, mkg/dm3 < 0.5 1.2 < 0.5 Nitrogen nitrate, mkg/dm3 < 5.0 8.4 < 5.0 Phosphorus (orthophosphates), mkg/dm3 45.3 70.0 23.1 Silicon, mkg/dm3 798.9 1615.1 389.0 Mass concentration of petroleum products, mg/dm3 < 0.005 0.009 < 0.005 Suspended matters, mg/dm3 13.60 37.30 7.90 Chlorophyll а, mkg/dm3 2.77 4.98 0.35 * insufficient data for obtaining the mean value

190 A water temperature of the Lunsky Bay was distributed over the area rather evenly and ranged from 11.7 to 13.6 ºС. The evenness of distribution was upset only at the deep-water stations 3 and 4, where the temperature was a little low than a mean one (12.0 ºС) at the surface, and in the near-bottom horizon at station 3 the minimum temperature estimate (9.7 оС) was observed. Salinity varied from 4.1 ‰ at the very northern station of the bay (station 9) to 29.7 ‰ in the central part of the bay (station 4). The mean salinity estimate of the bay was 20.0 ‰. The observed pH values varied from 8.00 to 9.05. The mean estimate was rather high and constituted 8.59. The maximum pH value was observed at station 1; at stations 4, 6, and 9 pH values were also close to maximum. We should note that a rather high content of oxygen in water was recorded at the same stations; this fact together with the higher pH indicates the intensive phytoplankton development. The minimum estimates were recorded in the near-bottom horizon of station 5. Concentrations of dissolved oxygen varied widely from 8.63 to 12.40 mg/dm3 (a near- bottom horizon of station 3 and station 4, respectively). The mean estimate of concentrations over the bay was 10.52 mg/dm3. We could not reveal a definite character in oxygen distribution as by area, so by depth. A content of nitrite nitrogen in water samples varied from 0.5 to 1.2 mkg/dm3; often concentrations occurred below the method sensitivity (< 0.5 mkg/dm3). Nitrogen nitrite was found in samples at stations 2, 3, 4, 5 and 8 located in the central part of the bay, and at station 9 in the northern part of the bay. The mean estimate of nitrite concentrations was 1.2 mkg/dm3. A content of nitrogen nitrate in the bay was very little; often concentrations occurred below a threshold of detectability of the method (< 0.5 mkg/dm3); in the rest cases they approached to the minimum estimates (5.0-8.4 mkg/dm3). Nitrates were found only at three stations (2, 3, 5). Phosphorus (orthophosphate) was found in concentrations from 23.1 to 70.0 mkg/dm3. The mean estimate was 45.3 mkg/dm3. The maximum estimate was recorded at station 7, minimum at station 1. Silicon concentrations ranged from 389.0 to 1615 mkg/dm3, averaged 789.9 mkg/dm3. The maximum estimate was recorded in water samples at station 8, minimum at station 7. Examinations of the Lunsky Bay water samples for petroleum hydrocarbons revealed the presence of PHC in concentrations of 0.009-0.005 mg/dm3 only in two samples (stations 1 and 6); in the rest cases concentrations occurred below a threshold of detectability of the method (< 0.005 mg/dm3). A distribution of suspended matters in samples of the bay waters was heterogeneous; concentrations ranged from 7.90 to 37.30 mg/dm3 (station 7 and a surface horizon of station 5, respectively); the mean estimate was 13.60 mg/dm3. The mean estimate of chlorophyll а concentration was 2.77 mkg/dm3 and varied from 0.35 (station 8) to 8.52 mkg/dm3 (station 2). Thus, estimates of concentrations of all the determined ingredients were within the standard or much lower the tolerance limit concentrations (List of fisheries standards …, 1999); often the concentrations of determined parameters were below a threshold detectability of the method. There was not revealed a special character of distribution for the studied hydrochemical parameters. Some stations with higher pH and dissolved oxygen concentrations were noted; this may be a consequence of intensive phytoplankton development.

191 6.3. Particle-size composition of bottom sediments in the Lunsky Bay

Statistic parameters of distribution pattern for all the studied particle-size fractions are given in Table 6.3.1

Table 6.3.1 Statistic parameters of contents of the particle-size fractions in the surface layer of the Lunsky Bay bottom sediments in July 2000 (n = 28, %) Fraction Xav σ Median Mode Min Max 10.0 2.4 8.6 0.0 0.0 0.0 43.9 10-5 2.0 3.8 0.0 0.0 0.0 11.1 5-2 3.2 7.2 0.0 0.0 0.0 24.9 2-1 8.1 12.8 1.0 0.0 0.0 46.7 1-0.5 2.9 4.7 0.4 0.0 0.0 16.2 0.5-0.25 12.8 13.8 7.8 2.6 2.6 51.0 0.25-0.1 22.0 20.4 9.6 8.3 0.3 64.2 0.1-0.05 3.6 5.3 0.9 0.9 0.1 25.7 0.05-0.01 20.5 18.1 16.5 38.5 0.0 46.4 0.01-0.005 11.9 12.1 8.3 27.4 0.0 27.4 <0.005 10.8 9.6 9.6 22.3 0.0 22.3

The maximum content was recorded for a fine sand fraction and small-aleurite silts. A coarse-fragmental group of sediments on the bottom of Lunsky Bay was weakly represented. The maximum content of coarse-grained fractions (coarse-fragmental and sand) was observed at the inlet, along bars separating the bay from the Okhotsk Sea, and at the mouth river sites, which could be related to the transit zones, where a thin fraction flowing away with rivers was not impeded. A distribution of sandy fractions showed a rather interesting picture: a location along the cyclonic circulation in the northern part with distinguishing a small “curl” of accumulation (due to a fine sand fraction). A distribution of aleurite and pelite fractions was close in general. Accumulation in the central parts of the bay, where a current becomes weaker, is common for these fractions. Suspended matters carried away by the rivers to the bay area pass through a geochemical barrier of the mouth zone. They move to the bay, where further their re-distribution and sedimentation in zones of unloading, caused by the occurrence of Zostera fields and weak currents on these areas, take place. A total of 5 types of ground occur in the bay: gravel, graveled sand, medium sand, fine sand, and small-sized aleurite silts. In accordance with the current scheme, transit zones, and accumulation, the most coarse sediments were observed along the bars and at the inlet to the bay; the most thin grounds were recorded in centers of the northern and southern parts of the bay. It was concluded that tidal phenomena, autumn raisings of the water level, and biological processes were the main factors in the bottom relief transformation and forming the bottom sediments. Materials, presented by rivers, form the weak debris cones. In the Lunsky Bay bottom sediments the occurrence of needles of the different kinds of conifers was noted. Flood phenomena practically do not influence upon the formation of the bay grounds as far as the rivers are very small and have not any developed water collections.

192 6.4. Content of pollutants in the Lunsky Bay

6.4.1. Content of pollutants in bottom sediments by the archive and literary data Petroleum hydrocarbons In 2000, a summarized concentration of petroleum products in samples of bottom sediments varied from 0.5 to 129.0 mkg/g, averaged 22.8 mkg/g of the dry weight. A spatial distribution of petroleum products was characterized by the higher levels of accumulation at the mouth sites of the rivers in the southern part, where the natural infiltration of thermal waters was observed. The maximum concentration of petroleum products was observed in the mouth of Kyrlni River. There the ground was represented by fine sand; that is why, high numbers of pollutants can be explained by the river exportation. A summarized concentration of petroleum hydrocarbons in the Lunsky Bay bottom sediments in July 2000 corresponded to the level of accumulation of these pollutants in the oil- gas regions, but lower compared to the polluted ones.

Metals Statistic parameters of the gross content of metals in the surface layer of bottom sediments at 24 stations of the Lunsky Bay are given in Table 6.4.1, active forms of metals in Table 6.4.2. Metals - Fe, Cu, Ni, Pb, Co, As, Cd and Hg occur in bottom sediments of the bay practically all in active forms and, consequently, may be included into the biological circulation. Ti, Ba and Al are the most frequent in the mineral form (Fig. 6.4.1). During the metal distribution over the bay, a large zone of accumulation was observed in centers of both northern and southern parts of the bay for the majority of metals (except for Ba and Hg); the distribution was practically the same for both a general content and active forms of metals. The levels of mercury content were the greatest in the region of the Tengi River mouth; gross barium – in the mouth of Kyrlni River.

Table 6.4.1 Statistic parameters of the gross content of metals in the surface layer of the Lunsky Bay bottom sediments in July 2000 (n=24, mkg/g of the dry weight) Metal Xav. σ Median Mode Min Max Сv. % Al, % 46.82 24.63 44.25 89.00 15.50 100.00 52.6 Fe, % 18.57 12.31 17.75 4.00 2.25 39.00 66.3 Ti 3015 1124 3275 4200 900 4500 37.3 Ba 478 135 438 400 250 850 28.3 V 77 44 80 30 10 150 57.4 Zn 52.9 31.8 59.5 85.0 9.5 107.0 60.0 Cr 39.1 22.7 40.0 10.0 7.5 73.0 57.9 Ni 13.5 9.0 13.5 6.0 1.0 27.0 66.8 Pb 11.3 5.2 10.1 15.0 4.5 25.0 46.0 Cu 11.0 7.8 10.3 5.0 1.0 22.0 70.9 Co 4.92 2.50 6.00 6.50 1.00 8.00 50.8 As 3.29 1.96 3.00 - 0.29 6.55 59.5 Cd 0.210 0.179 0.183 0.190 0.015 0.585 85.4 Hg 0.042 0.034 0.033 0.015 0.010 0.136 81.1

193 Table 6.4.2 Statistic parameters of content of the acid-dissolved metal forms in the surface layer of the Lunsky Bay bottom sediments in July 2000 (n=24, mkg/g of the dry weight) Metal Хav σ Median Mode Min Max Сv. % Al, % 6.84 4.51 7.44 2.50 0.75 14.63 65.9 Fe, % 15.49 12.47 11.25 28.75 1.00 38.00 80.5 Ti 168 120 125 75 20 500 71.2 Ba 46.6 13.8 44.5 38.0 30.0 75.0 29.6 Zn 36.6 25.3 41.3 65.0 2.5 70.0 69.2 V 29.5 20.7 30.0 5.0 5.0 62.5 70.1 Cr 16.1 10.8 18.2 6.3 1.3 31.3 66.8 Ni 12.7 9.2 13.4 5.0 0.5 25.0 72.4 Cu 10.5 8.0 10.2 1.0 1.0 21.5 76.1 Pb 9.9 7.2 9.4 1.3 1.3 20.0 72.9 Co 4.64 2.44 5.40 7.50 0.50 7.50 52.6 As 2.61 1.61 2.18 2.10 0.15 5.85 61.8 Cd 0.208 0.171 0.149 0.009 0.008 0.570 82.5 Hg 0.042 0.034 0.033 0.015 0.010 0.136 81.1

100000

10000

1000

100 вал кисл 10 концентрации 1 Al Fe Ba Ti V Zn Cu Cr Ni Pb Co As Cd Hg 0.1

0.01 металлы

Fig. 6.4.1. Content of metals in mineral and active forms in the Lunsky Bay in July 2000

Thus, summarizing the data of the 2000 survey, we may conclude: - Hydrochemical parameters of the bay range widely. Concentrations of the examined ingredients are determined by the influence of river and seawaters reflecting a behavior of the tide wave; - 5 types of ground are presented in the bay: gravel, graveled sand, medium-grained sand, fine sand, and small-sized aleurite silts. Coarse fractions are exported by rivers and located in places with strong currents, and they also inflow with seawaters and are distributed along the bars; thin fractions concentrate in the central parts of the bay; - The main source of metal incoming to the bay grounds is thin suspended matters of the terrigenous run-off. Metals concentrate in zones of accumulation together with thin fractions of 194 bottom sediments (in the central part of the bay). The obtained levels are not high; they are formed by natural factors, and may be considered as background; - A content of petroleum hydrocarbons in the bay bottom sediments is at the level of under-polluted regions.

6.4.2. Content of petroleum hydrocarbons in bottom sediments in 2002 Results of analysis of the bottom sediment samples from Lunsky Bay for the content of petroleum products are given in Table 6.4.3.

Table 6.4.3 A summarized concentration of petroleum products in samples of bottom sediments and results of the analysis quality control № st. Concentration of Mean divergence Extraction of ersatz standard, % petroleum products, of duplicates, % mkg/g Mean Relative standard deviation 1 2.06 5.1 95 22 2 2.06 3 23.7 4 3.32 5 0.51 6 2.03 7 3.42 8 7.87 9 < 0.5

As one can see from the given Table, the estimates of petroleum hydrocarbons (PHC) from the bottom sediment samples of Lunsky Bay varied in the rather narrow range from < 0.5 to 7.87 mkg/g. The exception was a deep-water station 3, where the concentration of petroleum hydrocarbons in bottom sediments was 23.7 mg/g. The definite regularities for the petroleum products distribution in bottom sediments were not found. The analysis of results of the quality control has shown that % of the duplicate divergence and % of the extraction of ersatz standard did not exceed the tolerance criteria of quality.

6.5. Microbiological researches in the Lunsky Bay

When studying a microbe cenosis in the Lunsky Bay in 2000, numbers of the following groups of microbe community in water (1 sample) and bottom sediments (2 samples, conditionally named stations 1 and 2) were determined: saprophyte heterotrophic microorganisms growing on RPA, marine heterotrophic organisms, sanitary-indicative microorganisms, proteolytic and amylolytic, petroleum-oxidizing, phenol-resistant, and metal- resistant organisms. Among individual physiological groups of the water body microorganisms, plankton and benthic communities of saprophyte heterotrophic microorganisms, responsible for the main biological processes (destruction and mineralization of organic matters) and taking part in the self-purification of water ecosystems from different organic compounds coming from the outside and being formed directly in water bodies, are significantly important. A group of saprophyte heterotrophic microorganisms consuming handy organic fertilizer and responsible for the water body eutrophication is one of such groups. Indices of abundance of this group of microorganisms are used along with hydrochemical and hydrobiological indices when estimating water quality (GOST, 1977; Zhukinsky et al., 1981). 195 The abundance of this microorganism group was about 103 cell/ml, in bottom sediments – 104 cell/ml (Table 6.5.1). A temperature of water and bottom sediments was not high and constituted 13 ºС and 10.9-15.4 ºС, respectively. However, as the previous studies of microflora in the Nyisky Bay have shown, the temperature factor does not have a decisive importance in the microorganism development. An oxygen regime and a content of organic matters and biogenic elements are a determining factor.

Table 6.5.1 Microorganism numbers in water and ground samples from the Lunsky Bay in 2000 Microorganism numbers In 1 ml of water In 1 g of ground (cell/g) (cell/ml) St. 1 St. 2

Saprophyte (RPA) 103 104 104 Marine heterotrophic 103 104 104 (Yoshimitsu-Kimura) BGEB (Endo) 0 0 0 PEB (Ploskirev) 0 0 0

Numbers of the isolated from the bay water saprophyte heterotrophic microorganisms correspond to the literary data. Thus, there is information that due to remoteness from a shore, enrichness with organic matters, and a season, a numbers of microorganisms in 1 ml of water may fluctuate from several thousands to several millions. In bottom sediments of surface layers of the shallow lagoons, atolls, estuaries, and bays the number of saprophytes was recorded within 102-105 cell/g (Mishustina, 1985). Numbers of microorganisms in grounds do not depend on the capacity of water column covered them. A particle-size composition of bottom sediments affects greatly the bacteria inhabiting them. There are more bacteria in thin-dispersed clay depositions compared the sandy ones. Another factor affecting a distribution of microorganisms in grounds is a close location of the region to the sites with the higher drift of terrigenous material enriched with organic matters (Mishustina et al., 1985). Slimy-sand bottom sediments of Lunsky Bay, enriched with plant residuals, determined a rather high abundance of saprophyte heterotrophic microorganisms: in two examined sampled it was the same (ten thousands cells per 1 g), a number of this group in water sample was an order of magnitude lower. Halotolerant microorganisms (marine heterotrophic microorganisms) able to destroy organic compounds and assimilate carbon sources under the changing regime of salinity, occupy a significant place in the structure of bacterial community. In the examined sample their number was the same as for saprophyte heterotrophic microorganisms growing on RPA (Table 6.5.1). Indices of abundance for sanitary-indicative microorganisms, along with the indices of abundance for heterotrophic group, are used during the estimation of quality of the natural waters; they are indicators of the anthropogenic economic-domestic impact on marine environment and indicate the biological pollution. Bacteria of the group of enteric bacillus (BGEB) and some other groups of pathogenic enteric bacilla (PEB) are the most recognized and distributed all over the world sanitary-indicative microorganisms (GOST, 1977; Zhukinsky et al.,1981). Sanitary-indicative microorganisms being indicators of biological pollution were not found in the water and ground samples (Table 11). Lunsky Bay is less undergone to the impact of the man’s economic activity compared to other bays of northeastern Sakhalin. There are no large inshore settlements, near which, as a rule, bacteria of these groups are being found in water and ground, and from which indicator microorganisms can be brought with domestic run-off (Korsh, Artemova, 1978). Low temperatures of water and ground (10.9 – 15.4 ºС) did not promote a development of sanitary-indicative mesophyll microorganisms either. 196 Biological pollution of a water body is determined by the presence of heterotrophic, conditionally-pathogenic, and pathogenic microorganisms in water, and also by the content of biopolymers (proteins, lipids, and polysacharides) and amylolytic decomposing them. A great number of microorganisms: destructors of biopolymers (proteolytic and amylolytic) were found in the examined samples of the bay water and bottom sediments. Proteolytic microorganisms in water sample constituted 27 % , in bottom sediments (1 sample) – 10.6 % of the number of distinguished saprophytes. Amylolytic microorganisms were determined only in samples of bottom sediments and constituted 12 and 53 % of the saprophyte number (Table 6.5.1). Some authors indicate the fact that a higher content of active amylolytic microorganisms may be found in conditions of a specific biological pollution caused by the biomass of dead macrophytes (Dimitrieva, Dimitriev, 1996); this was observed in places of bottom sediment sampling in the bay. Bottom sediments contained remains of alive and dead Zostera marina. Significant numbers of these groups of microorganisms indicate the intensive processes of decomposition of the organic matters, their mineralization, and active processes of the water body purification. Hydrocarbon-oxidizing microorganisms being widely distributed over different areas of the World Ocean play an important part in the complex of processes of the water body purification; in particular, paraffin-oxidizing bacteria are the common components of marine ecosystems (Mironov, 1971; Gusev, 1980; Koronelli et al., 1987). Mainly, non-sporiferous bacteria, fungi, yeast, and proactinomycetes may realize the oil degradation in seawater of different latitudes. Numbers of bacteria growing due to the petroleum hydrocarbons reach 106- 107 cells per 1 l of seawater (Verbina, 1980). A direct dependence between the concentration of petroleum hydrocarbons in water and bottom sediments and the content of petroleum-destroying microorganisms has been shown by many researchers (Mironov, 1971; Kvasnikov, Klushnikova, 1981). This gives a base to use them as indicators of pollution of marine environment with hydrocarbons (Verbina, 1980). The following data on the abundance of petroleum-oxidizing sea flora are given in literature: in places of the chronic pollution their numbers reach 103-105 cell/ml, that constitutes from 35 to 80 % of the population of all saprophytes; under the accidental oil spill their number may increase during a short time period to 107-109 cell/ml; in bottom sediments of the coastal and open ocean areas the abundance fluctuations of hydrocarbon-oxidizing bacteria are significant (from 10 to 109 cell/g of silt (Mishustina, 1985). In the bay the number of petroleum-oxidizing microflora was determined only in one sample of ground - 103 cell/g (Table 6.5.2). The number estimates of this group are rather high. Some authors (Mishustina, 1985) advise to interpret the obtained data on hydrocarbon-oxidizing microorganisms regarding to coastal waters and open areas with a caution, and simultaneously use the data of chemical analysis.

Table 6.5.2 Abundance of oil-oxidizing and phenol-resistant microflora of the Lunsky Bay Microorganism numbers In 1 ml of water In 1 g of ground (cell/g) (cell/ml) st. 9 st. 1а st. 5 Oil-oxidizing 0 - 103 Phenol-resistant 102 103 103

Under the pollution of water environment, phenol-resistant bacteria are registered by different phenol compounds, which are divided into autochthonous and allochthonous by their nature. The first compound is being formed as a result of functioning of all the trophic links of ecosystem in general, under the microbiological destruction and transformation of various organic compounds being formed during the process of vital activity of the whole community (Kondratyeva et al., 1998; Saralov et al.,1979). The second compound come from the outside, as 197 a result of anthropogenic impact - a man’s economic activity. A number of phenol-resistant bacteria is a reliable indicator of the water environment pollution with phenol compounds, and some authors indicate a correlation between the number of phenol-resistant bacteria and excess of phenol tolerance limit content (TLC) in natural waters (Dimitrieva, 1995). In the Lunsky Bay a number of this group of microorganisms in water sample was 1.0 thousand cell/ml, in bottom sediments it was an order magnitude higher (Table 6.5.2). Phenol concentrations in water ecosystems may vary by seasons and differ in surface and near-bottom water layers. Slimy bottom sediments and sites with intensive development of algae and macrophytes are, as a rule, zones with the high content of phenol compounds (Saralov et al.,1979). Such zones are common for majority of the studied bays; this can also explain a significant abundance of phenol-resistant bacteria. A total of 6 groups (Zn, Fe, Ni, Cd, Pb, Cu) of metal-resistant microorganisms were determined in water and bottom sediment samples. Pollution with heavy metals is one of the dominating kinds of pollution common for the Far East seas due to the natural and anthropogenic reasons. The coastal waters of Prymorye contain a wide spectrum of heavy metals with different levels of concentrations: from background to significant (more than 3 TLC) (Dimitrieva, Bezverbnaya, 1999). Abundance of metal-resistant organisms is used by some authors during a microbe indication of the natural waters pollution with different metals (Bezverbnaya et al.,1999; Dimitrieva, Bezverbnaya, 1999). Microbiological criteria for determining concentrations of different heavy metals in seawater have been created (Dimitrieva et al., 1999). A number of iron-resistant microorganisms was the highest in the examined bottom sediments of the Lunsky Bay (Table 6.5.3). This is explained by geochemical peculiarities of the study region with the domination of peat strata containing a significant number of iron. The number of copper-resistant microorganisms, which index a higher content of copper in bottom sediments is high too. There are the literary data, which note the increase in zinc and copper concentrations both in the environment and organisms inhabiting it in zones exposed to the anthropogenic impact (Lunsky Bay as well) (Malinovskaya, Khristoforova, 1997). Nickel and lead are the markers of geochemical background; their concentrations are always higher in the oil-gas regions, to which a studied bay and total northeastern Sakhalin are related (Latkovskaya, 1999). Evidently, this explains rather high indices of abundance of nickel- and lead-resistant microorganisms in water and bottom sediments. A situation during microbe indication of heavy metal pollution in bays Nyisky and Piltun was analogous (Latkovskaya, 2000; Labay, 1999).

Table 6.5.3 Relative numbers of metal-resistant microorganisms of the Lunsky Bay microbe community in 2000 (% of the total number of heterotrophic microorganisms) Microorganism numbers Groups of water ground microorganisms st. 1 st. 2 Zn- resistant - 25.0 52.17 Fe- resistant - 98.3 95.0 Cu- resistant 56.8 81.6 95.0 Ni- resistant 31.8 51.6 60.8 Cd- resistant 5.0 - 4.3 Pb- resistant 77.27 60.0 73.0 proteolytic 27.3 0 10.6 amylolytic - 12.0 53.0

198 6.6. Phytoplankton of the Lunsky Bay

6.6.1. Description of phytoplankton by the archive and literary data In July 2000, a total of 202 species and intraspecific taxons belonging to 7 divisions were found in the surface waters of Lunsky Bay: Bacillariophyta – 145 species and intraspecific taxons, Dinophyta – 42, Chlorophyta – 10, Crysophyta –5, Euglenophyta – 4, Cryptophyta – 4, Cyanophyta – 2. Among diatom algae, genera Navicula (30 species), Nitzschia (17), Amphora (8), Achnanthes and Chaetoceros (by 7) were the richest by species, among dinoflagellate algae – Gymnodinium (11). Phytoplankton abundance in the bay varied from 20 thousand cell/l to 9 million cell/l, averaged 1.37 million cell/l; biomass from 14.163 mg/m3 to 8.67 g/m3, averaged 1.5 g/m3. The maximum species composition was found in the narrowest part of the bay near the mouth of Kavle River. Freshwater, marine, and freshwater-brackish species prevailed in the phytoplankton species composition. Diatom and dinoflagellate algae dominated by abundance on the major part of the bay area, yielding to cryptophyte and bluegreen algae only at some sites; diatom, dinoflagellate, and chrysophyte algae dominated by biomass. A chrysophyte Ebrea tripartita (Schumm.) Lemm, diatom Odontella aurita Ag., and dinoflagellates Dinophisis acuta Ehr., Heterocapsa triquetra and Diplopsalis lenticula Bergh were developing in mass. In addition to algae, provoking “water blooming”, the following toxic species provoking “red tides”: Dinophysis acuta Ehr, D. acuminata Clah. et Lachm., D. rotundata Clap. et Lachm.were found in the surface waters of Lunsky Bay (Latkovskaya et al., 2001).

6.6.2. Characteristic of phytoplankton in 2002 A floristic composition of the Lunsky Bay in September 2002 was formed by 8 divisions of microalgae: diatoms Bacillariophyta, dinoflagellates Dinophyta, green Chlorophyta, cryptophytes Cryptophyta, euglenic Euglenophyta, chrysophytes Chrysophyta, bluegreen Cyanophyta, rhaphydophytes Rhaphydophyta. A total of 187 species and intraspecific taxons were found. Diatoms (69 % of the total number of species) and dinoflagellates (19 %) occupied the leading places by the number of species. Proportions of the rest divisions were insignificant in formation of the species composition (Appendix 2.6.1). Diatom Melosira sulcata (Ehr.), Amphora coffeaeformis Ag., green Pyramimonas sp., and cryptophyte algae Plagioselmis punctata Butch., Plagioselmis sp. occurred almost everywhere. Hydrologic instability and shallow waters of the bay caused the heterogeneity of phytoplankton spatial distribution. The maximum numbers (551,417 thousand cell/l – 1,023 million cell/l) were recorded in the surface waters at stations located at the outlet of the bay to the sea, where the abundant development of both freshwater (brought with the Yasynge River run-off) and marine (resulted from the influence of tidal saline waters on the bay) microalgae species was observed. The maximum biomass estimates (851,292-962,172 mg/m3) were recorded at station 6 of the above site and station 8 located near the mouth of Kyrlnyi River; this was caused by the development of marine littoral diatom alga Cocconeis scutellum (Ehr.) (station 6), euryhaline alga being frequent in the river estuaries, and diniflagellate alga Heterocapsa triquetra (Ehr.) Stein. (station 8). Station 7, where phytoplankton was represented, mainly, by marine and brackish-marine species, was characterized by the minimum estimates of quantitative indices. There, abundance was 7,536 thousand cell/l, biomass 7,876 mg/m3. Analysis of the vertical distribution of phytoplankton (for two the most “deep-water” stations) showed that maximum estimates of abundance and biomass caused, mainly, by the development of marine (in conditions of the higher salinity) cryptophyte algae from the genus Plagioselmis, were recorded in the near-bottom layer. 199 On average, abundance and biomass estimates in the study region constituted 395,88 thousand cell/l and 474,43 mg/m3, respectively. Almost at all stations of the bay the dominants by numbers were: cryptophytes Plagioselmis sp. (22-66 % of the total abundance), Plagioselmis punctata Butch. (23-66 % of the total abundance), excluding stations 4, 6, and 8, where diatoms Cocconeis scutellum (27-95 %; stations 4 and 6), and Heterocapsa triquetra (82 %; station 8) were abundant. The two latter species dominated at the pointed stations by biomass too: Cocconeis scutellum constituted 90 % of the total biomass; Heterocapsa triquetra – 95 %. Along with them, (at station 3 in surface and near-bottom layers) a large dinoflagellate Noctiluca scintillans (Macart.) Kof.et Sw. (54-68 % of the total biomass), often causing “water blooming” near the shore, entered the group of dominants (Appendix 2.6.2).

6.7. Zooplankton of the Lunsky Bay

6.7.1. Description of zooplankton by the archive and literary data In July 2000, a total of 34 forms of organisms belonging to 16 groups were found in samples. Due to the relatively small depth of the bay, a high number of the near-bottom forms were noted in samples. Ten forms of 34 were facultative-planktonic, that is, related to the nektobenthos (cumaceans) and planktobenthos (major harpacticides, hydracarines, ostracods). Majority of species were related to brackish and euryhaline (Sinocalanus tenellus, Tachidius discipes). At the most freshened sites there were freshwater species enduring salinity (Chydorus sphaericus), and at the most saline – marine coastal species enduring freshening (Acartia hudsonica, Pseudocalanus newmani, Podon leuckarti). A group of copepods was the richest both in quantitative and qualitative respects. In the bay it was represented by three suborders: Calanoida and Cyclopoida (typical plankters), and Harpacticoida (planktobenthos). All of them are important food organisms and form the base for feeding the fish-planktophagans in the bay. Major copepod females had spermatophores or egg sacs, and a number of nauplii was high too; this proves the period of copepod mass spawning. Cladoceres (Evadne nordmani, Podon leuckarti) and rotifers (Synchaeta sp., Euchlanis lucksiana) can be related to the important food organisms too, being abundant in the bay. The latter are especially important for juveniles feeding. By the Shoener’s index, two similar zooplankton complexes being, evidently, of temporary character were distinguished. The group Acartia hudsonica – Nauplii copepoda. Its mean biomass was 318 mg/m3, mean abundance 32855 ind./m3. Copepodids of Acartia and nauplii of copepods (mainly of the same species) dominated, reaching 63,7 % of the total community biomass. The group Acartia hudsonica – Eurytemora pacifica. Its mean biomass was 1182 mg/m3, mean abundance 103440 ind./m3. Copepodids of Acartia and Eurytemora dominated, reaching 86% of the total community biomass (Latkovskaya et al., 2001).

6.7.2. Characteristic of zooplankton in 2002 Zooplankton was unevenly distributed over the bay area. This is connected with some factors: a level of mineralization and water temperature, affect of river, brook and tide run-off, uneven bottom relief, vegetation development. The bay zooplankton is presented by two complexes (Fig. 6.7.1), which detail description is given in Chapter 2 (Piltun Bay). A total of 14 species and forms of organisms belonging to 6 taxonomic groups were found in samples (Table 6.7.1); of them, copepods were the most diverse (7 forms). High numbers of the near-bottom forms were recorded in samples due to the relatively small depth of the bay. Majority of species were related to brackish and euryhaline ones. Numbers of zooplankters (Table 6.7.2) in the bay varied within 945,0–287526,8 ind./m3, biomass 12,74–1775,07 mg/m3, averaged 328,20 mg/m3. The first community constituted the maximum biomass. Nauplii of different copepods prevailed both by abundance and biomass. 200

Table 6.7.1 A list of organisms from the Lunsky Bay in 2002 № Group Form 1 Protozoa Tintina sp. 2 Rotatoria Synchaeta sp. 3 Coelenterata Obelia longissima 4 Evadne nordmanni Cladocera 5 Podon leuckarti 6 Pseudocalanus newmani 7 Eurytemora pacifica 8 Acartia clausi 9 Copepoda Halicyclops sp. 10 Oithona similis 11 Harpacticoidae indet. 12 Nauplii copepoda 13 Cypris. cirripedia Cirripedia 14 Nauplii cirripedia

Table 6.7.2 Zooplankton abundance and biomass by stations № st. lu1 lu2 lu3 lu4 lu5 lu6 lu7 lu8 lu9 287526, N, ind./m3 945,0 4750,0 178509,0 3800,0 8 2125,0 1200,0 49475,0 2725,0 B, mg/m3 12,74 96,70 691,64 47,75 1775,07 24,88 17,43 247,78 39,88

201

Fig. 6.7.1. Distribution of zooplankton complexes in the Lunsky Bay in 2002

202

6.8. Benthos of the Lunsky Bay

6.8.1. General characteristics of benthos Practically, there are no archive and literary data containing any description of the Lunsky Bay bottom fauna and flora. Of all published and manuscript materials accessible for authors, only one report of DMIGE (Krasavtsev, 1991) contained scanty information about macrobenthos composition presented by a very smal list including 20 species, the base of wich was formed by amphipods. In July 2000, a dredged survey in the Lunsky Bay was carried out by the complex expedition of SakhNIRO, by the results of which a description of benthos including the list of species and distribution of the main quantitative characteristics was done (Latkovskaya et al., 2002). A total of 28 benthos samples were collected with the help of Petersen's grab (0.025 m2). Sample processing was carried out in the Laboratory of Applied Ecology of SakhNIRO. In total, in July 2000, about 100 species of benthos and nekto-benthos organisms were found in dredged samples (Appendix 6.8.1). Analysis of benthos species composition proves its marine-euryhaline origin; this is the Lunsky Bay’ difference from other bays analyzed in this report, where the base of benthos is formed by brackish species. As one can see from Table 6.8.1, benthos of the Lunsky Bay was presented by 32 taxons. Benthos numbers in the bay were high and varied by stations from 180 ind./m2 in the southern part of the bay to 20350 ind./m2 at the northeastern site of the bay. The mean abundance was 2731 ± 807 ind./m2 (Table 6.8.1). The minimum numbers were recorded in the basin of the southern part of the bay at station 11 on silty ground at more than 4 m depth. The maximum estimates of abundance were recorded at station 2 on silty ground at small depth. Among bottom organisms, meiobenthos forms (nematodes and oligochaetes) dominated by numbers. Nematodes constituted 34 % of the total benthos abundance, a proportion of oligochaetes was 18 % (Fig. 6.8.1). Among macrobenthos organisms, the high abundance was recorded for gastropods, polychaetes, amphipods, and bivalves.

Table 6.8.1 Main quantitative indices of various benthos taxons in the Lunsky Bay in July 2000 Taxon Abundance, ind./m2 Biomass, g/m2 Frequency, % Actiniaria 78 6.58 11 Amphipoda 139 0.62 89 Bivalvia 120 14.10 56 Copepoda 1 0.00 7 Chlorophyta 0 0.12 4 Cirripedia 19 8.34 4 Cumacea 35 0.47 19 Decapoda 1 0.16 11 Dinophyta 2 0.00 19 Diptera 56 0.07 19 Echinodermata 8 0.00 4 Foraminifera 78 0.00 4 Angiospermae 0 8.62 19 Gastropoda 363 8.12 63 Hirudinea 8 0.06 11 Holothuroidea - 0.03 4 203 Taxon Abundance, ind./m2 Biomass, g/m2 Frequency, % Hydrachnidia 21 0.00 15 Hydrozoa 2 0.00 7 Insecta 1 0.00 4 Polychaeta 333 1.85 74 Isopoda 26 0.31 26 Mysidacea 4 0.00 11 Nematoda 887 0.43 59 Nemertini 1 0.01 7 Oligochaeta 462 0.06 44 Opisthobranchia 7 0.01 4 Others 8 0.01 7 Phaeophyta 0 3.40 4 Pisces 25 0.00 30 Sphenophyta 0 0.81 4 Rhodophyta 0 0.19 4 Sipunculida 0 0.00 4 Mean 2731,48 ± 807 54, 45 ± 15,21

Amphipoda 11% 5% 4% Bivalvia 3% 13% Gastropoda 18% Polychaeta Nematoda Oligochaeta

12% Actiniaria Прочие

34%

Fig. 6.8.1. Ratio between numbers of the main groups of dredged benthos in the Lunsky Bay in July 2000

Representatives of the genera Falsicingula and Littorina were the most abundant among gastropods, and Аmpharete arctica among polychaetes. Abundance of these species at stations exceeded 1000 ind./m2. The mean benthos biomass was 54,45 ± 15,21 g/m2 (Table 6.8.1). Benthos biomass varied from 0,4 g/m2 at the strait site of the bay on graveled sand, where strong tidal currents negatively insluenced upon the bottom biota, to 298,16 g/m2 at station 22 located in the narrow channel joining northern and southern parts of the bay on graveled sand with shell rock at more than 4,5 m depth. 204 Bivalves dominated among zoobenthos by biomass (Fig. 6.8.2). They were represented by 5 species. The main contribution to the total bivalve biomass was made by Lyocima fluctuosa (over 100 g/m2 at individual stations). Biomass of Macoma balthica did not exceed 14 g/m2. We should note that this species, cenosis-forming in other described lagoons, in samples was represented by juvenile specimens. Flowering plants dominated among vegetable organisms; their biomass constituted 16 % of the total benthos biomass. Vascular plants were represented, mainly, by two species: Zostera japonica and Zostera marina. Biomass of Zostera in the coastal zone of northern part of the bay reached 100 g/m2 (station 2). Cirripedes and gastropods constituted 15 % of the total biomass. But, taking into account the fact that Cirripedia (genus Balanus) were observed only at one station in the narrow part of isthmus (station 22; 225 g/m2), a rope of this group in forming the bottom biomass of Lunsky Bay was much lower.

Actiniaria Bivalvia 6% 12% Gastropoda 16% Polychaeta Cirripedia Phaeophyta Embryophyta 6% 27% Прочие 15% 3% 15%

Fig. 6.8.2. Ratio between biomasses of the main groups of the Lunsky Bay dredged benthos in July 2000

Gastropods were represented by 8 species. Брюхоногие моллюски были представлены 8 видами. Littorina kurila and L. sgualida formed the greatest biomass. Actinians, indefinite up to species, were one more significant group (12 % of the total biomass). A distribution of the total numbers of bottom hydrobionts (without meiobenthos organisms) was rather heterogeneous. In general, four sites with the higher concentration of bottom organisms can be distinguished. Contributions of different benthos groups into the formation of general abundance were not equal in the indicated zones of the higher numbers; this proves the absence of the unique benthos community on the bay area. The highest concentrations of bottom organisms were observed along the northeastern shore of the bay (station 2) and in the channel joining the northern part of the bay with the southern one (station 22). In the first case, the main abundance was formed by foraminiferes, gastropods, polychaetes, and, to a less extent, by bivalves; a total number of organisms reached there 7000 ind./m2. Cirripedes, polychaetes, and bivalves dominated in the region of channel at more than 4 m depth on sand grounds; numbers of invertebrates constituted more than 3000 ind./m2. A site of the higher concentration of benthos organisms (2000-3000 ind./m2) was isolated in the southeastern part of the bay at stations 10, 14, 15, and 16. At different stations from this site, various benthos groups were the most mass: station 14 – gastropods, stations 10 and 15 – polychaetes, station 16 – bivalves. One 205 more zone of higher abundance was distinguished in the northwestern part at stations 5 and 6, where gastropods were the most mass. A distribution of the total macrobenthos biomass was heterogeneous too (Fig. 6.8.3), but in contrast to abundance, zones of high biomass were attached to the bay fairway along its eastern coast. The maximum biomass estimates were recorded at the site extended along the eastern shore of the bay from the isthmus towards the northern part; grounds at this site were different and represented by various types from sand-graveled to fine aleurite silts. There, biomass did not exceed 200 g/m2. Another site of the higher biomass (to 100 g/m2) was recorded in the littoral zone along the southeastern shore of the bay. Organisms dominating by biomass at the indicated sites were related to different species: Balanus sp. dominated in the region of channel (station 22), Zostera marina – at station 2, bivalve Liocyma flyctuosa – at station 3. Actinians and bivalve Macoma balthica, indefinite up to a species, dominated along the southeastern shore of the bay on silty grounds. The near-mouth sites of rivers and brooks were characterized by low estimates of macrobenthos biomass.

206

Fig. 6.8.3. Distribution of benthos biomass in the Lunsky Bay in 2000 (according to Latkovskaya et al., 2001)

207

6.9. Ichthyofauna of the Lunsky Bay

At present, the lowest fish species diversity among the considered bays has been noted in the Lunsky Bay. By the literary data and SakhNIRO archive materials, the bay ichthyofauna includes 27 species of fish and fish-like species (Latkovskaya et al., 2002; Safronov et al., 2003) (Table 6.9.1). Large rivers are not flowing into this bay. Abundance and biomass of some anadromous species (Pacific salmon, stone loach Salvelinus and others) are small enough. Individual anadromous species do not reproduce in water-courses flowing into the bay, but enter it for feeding (Sakhalin taimen Parahucho perryi, redfins Tribolodon, and others). Abundance and biomass of euryhaline fishes (starry and banded flounders, flathead sculpin, and others) are relatively stable. Changes in fish abundance and biomass in the bay during a year depend, mainly, on numbers of anadromous and marine species entering the bay from the sea for feeding. Regularities of variation of these values, common for other bays, do not become apparent in this water body.

Table 6.9.1 A list of fish and fish-like species of the Lunsky Bay Family Species and subspecies Petromyzontidae Lethenteron japonicum – arctic lamprey **Clupea pallasii – herring Clupeidae ****Sardinops sagax melanosticta – west Pacific sardine Oncorhynchus gorbuscha – pink salmon Oncorhynchus keta – chum salmon Oncorhynchus masou – masu salmon Salmonidae Oncorhynchus kisutch – coho salmon ***Salvelinus leucomaenis – Sakhalin char *** Salvelinus malma krascheninnikovi – southern malma *Parahucho perryi – Sakhalin taimen Mallotus villosus – capelin Hypomesus nipponensis – wakasagi Osmeridae Hypomesus olidus – pond smelt Osmerus mordax dentex – Asiatic smelt ***Tribolodon brandtii – eastern redfin Cyprinidae ***Tribolodon hakuensis – big-scaled redfin Gadidae **Eleginus gracilis – saffron cod Mugilidae Mugil cephalus – Pacific mullet Gasterosteus aculeatus – threespine sticleback Gasterosteidae Pungitius sinensis – Amur stickleback Zoarcidae Zoarces elongates – Pacific eelpout Hexagrammos octogrammus – masked greenling Hexagrammidae Pallasina barbata – tubenose poacher Agonidae Brachyopsis segaliensis – long-snouted poacher Cottidae Megalocottus platycephalus – flathead sculpin ***Platichthys stellatus – starry flounder Pleuronectidae Liopsetta pinnifasciata – banded flounder * Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the last years 208 Brackish and marine species formed the bay ichthyofauna. By the data of our surveys, freshwater sites in the bay occupied small areas; this explains the absence of freshwater fish species. Majority of fish found in the bay are related to the commonly marine species. Anadromous fishes were represented by pink, masu, chum, and coho salmon, Pacific redfins and Asiatic smelt, and also arctic lamprey. In July, during the study period, pink and chum runs for spawning took place, and juvenile coho salmon migrated downstream to the sea. Of anadromous fishes, Sakhalin taimen, Sakhalin char, and pond smelts were found too. Of marine species, herring, Asiatic smelt, Pacific eelpout, masked greenling Hexagrammos octogrammus, starry flounder, banded flounder, and others were found. In July 2000, threespine stickleback prevailed from catches (100,0 %) by frequency (Table 6.9.2). Flathead sculpin and starry flounder were widely distributed over the bay area (by 66,7 %). Pond smelts, Pacific redfins, and Amur stickleback (by 55,6 %) occurred rarer in catches. Frequency of other species constituted from 11,1 to 44,4 %. Capelins’ spawning was observed in the sea part of the bay during the study period. Capelin was one of the most mass species in this period (July). A great abundance of capelin could be indirectly confirmed by the fact that many species (Sakhalin char, Pacific redfins, flounders, and flathead sculpin) often had capelin in their stomachs. Fish abundance and biomass in the coastal zone varied widely: from 0,0002 to 0,4378 ind./m2 and from 0,0002 to 2,3048 g/m2, averaged 0,0421 ind./m2 and 0,6856 g/m2 (Table 6.9.2). The highest abundance was observed for pond smelt (0,0777 ind./m2), Amur stickleback (0,0323 ind./m2), banded flounder (0,0281 ind./m2), Pacific redfins (0,0278 ind./m2). Threespine stickleback (2,3048 g/m2) and banded flounder (2,1798 g/m2) prevailed by biomass.

Table 6.9.2 Fish frequency, abundance and biomass in the Lunsky Bay in July 2000 from the beach seine catches Mean Mean biomass, Relative Species Frequency, % abundance, g/m2 biomass, % ind./m2 Oncorhynchus gorbuscha 22,2 0,0011 1,4626 13,332 Oncorhynchus kisitch 22,2 0,0017 0,0088 0,080 Salvelinus malma 22,2 0,0008 0,8383 7,642 krascheninnikovi Salvelinus leucomaenis 44,4 0,0022 0,2196 2,002 Osmerus mordax dentex 44,4 0,0066 0,0875 0,797 Hypomesus olidus 55,6 0,0777 0,7780 7,092 Mallotus villosus socialis 11,1 0,0220 0,2150 1,960 Tribolodon spp. 55,6 0,0278 0,9567 8,721 Gasterosteus aculeatus 100,0 0,4378 2,3048 21,010 Megalocottus 66,7 0,0059 0,8013 7,304 platycephalus Zoarces elongatus 33,3 0,0020 0,1370 1,249 Pungitius sinensis 55,6 0,0323 0,0497 0,453 Eleginus gracilis 22,2 0,0011 0,0290 0,264 Brachyopsis segaliensis 11,1 0,0002 0,0002 0,002 Platichthys stellatus 66,7 0,0255 0,9020 8,223 Liopsetta pinnifasciata 33,3 0,0281 1,1795 19,868

A specialized salmon fishery has not been conducted in the bay. As a rule, in recent ten years not more than 10-12 trap nets have been settled for the winter fishery. Due to the remoteness of the water body from localities, sampling the biological material in winter period is 209 carried out episodically. Saffron cod and flathead sculpin were the commercial objects in this period, smelts and flounders were sampled as bycatch. Patrimonial communities «Lunvo» and «Ungir» are located on the bay shore. A total of 10 persons live there.

6.9.1. Main commercial species Of Pacific salmon, pink, chum, masu, and coho spawn in rivers flowing into the bay. Pink salmon (in odd years significantly) and chum salmon are the most abundant. The total area of salmon spawning grounds in rivers flowing into the Lunsky Bay is 20100 m2 (Table 6.9.3) (Report…, 1957).

Table 6.9.3 Rivers and spawning grounds for Pacific salmon in the basin of Lunsky Bay Spawning area, Species of River Length, km Water area, km2 m2 Pacific salmon Kavle 6 no data 100 pink, chum Kiri 26 35,4 20000 pink, chum

Pink salmon Dates of anadromous and downstream migrations of pink salmon and its biology do not differ significantly compared to other water courses of northeastern Sakhalin. Under the mean density of pink spawners of 140 ind./100 m2, in total, 28,1 thousand fish pass through the area of Lunsky Bay during anadromous migration. At the mean long-term weight (1,22 kg) of one individual, the mean pink salmon biomass constitutes 34,3 t. In odd years, 0,4 million pink fry migrate downstream through the bay area to the sea for feeding, in even years – 2,0million fry. In July 2000, during the expedition works, pink salmon occurred only in the channel and mouth of Kiri River. Fish lengths varied from 41,0 to 57,0 cm, weights from 850 to 2800 kg (Fig. 6.9.1, 6.9.2). Majority of fish had gonads at III stage of maturity. A specialized fishery is not conducted in the bay.

30

20 % 10

0 40 42 44 46 48 50 52 54 56 58 Длина, см

Fig. 6.9.1. Distribution of pink salmon by their body lengths in July 2000 in Lunsky Bay (n = 48)

210

40 30

% 20 10 0 600 900 1200 1500 3000 Масса, г

Fig. 6.9.2. Distribution of pink salmon by their body weights in July 2000 in Lunsky Bay (n = 48)

Chum salmon Chum salmon abundance is low in rivers flowing into the bay. Its specialized fishery is not conducted.

Masu and coho salmon These species occur sporadically. Fishing is not conducted. The absence of the specialized fishery in the bay is connected, first, with the low abundance of Pacific salmon in the bay basin. The water body is also significantly outlying from the localities, and no good routes approach it.

Fishing sites exploited by the companies in Lunsky Bay are presented in Table 6.9.4 (A list …, 1998).

Table 6.9.4 Fishing sites exploited by the companies in Lunsky Bay № of site Borders Extension, km User Southern extremity of Vysokiy 1 Island – northern boundary of 14 Consolidated Fund Lunsky Bay

Saffron cod Saffron cod is not abundant in the Lunsky Bay. The bay is not very important for its fishing. There are no complete data on the biological state of saffron cod. By the obtained data, saffron cod lengths from catches varied from 19,0 to 46,0 cm (Fig. 6.9.3). A catch of saffron cod varied from 0,2 (1998) to 5,6 t (1992), averaged 1,2 t. A number of gear changed from 4 (2002) to 10 units (2000), averaged 6 units.

211

18.00 16.00 14.00 N = 311 экз. X = 30.95 см 12.00 10.00 % 8.00 6.00 4.00 2.00 0.00 20 22 24 26 28 30 32 34 36 38 40 42 44 46 Длина АС, см

Fig. 6.9.3. Distribution of saffron cod by lengths in the Lunsky Bay in March 1993

Flathead sculpin This species was frequent from catches in July 2000, constituting a significant portion among other fish species by biomass. Lengths of the caught specimens varied within 7,5 – 33,7 cm, weight 7,0-414,0 g (Latkovskaya et al., 2002). Specimens of 9,0-15,0 cm prevailed by the length, by weight those from 10 to 90 g, at 1+ and 2+ age (Fig. 6.9.4, 6.9.5, 6.9.6).

25 20 15 % 10 5 0 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 Длина, см

Fig. 6.9.4. Distribution of flathead sculpin by lengths AD in the Lunsky Bay in July 2000 (n = 39)

40 30

% 20 10 0 0 20 40 60 80 100 150 200 400 600 Масса, г

Fig. 6.9.5. Distribution of flathead sculpin by body weights in the Lunsky Bay in July 2000 (n = 21) 212

50 40 30 % 20 10 0 0+ 1+ 2+ 3+ 4+ 5+ 6+ Возраст, лет

Fig. 6.9.6. Age composition of flathead sculpin in the Lunsky Bay in July 2000 (n = 21)

A flathead sculpin dominates in commercial catches in the winter period. A quantitative ratio from catches is given in Fig. 6.9.7. A catch of flathead sculpin in the bay varied from 29 t (1992) to 88 t (1991).

Полосатая камбала

Корюшка

Плоскоголовый бычок

Навага

0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 % по биомассе

Fig. 6.9.7. Composition of catches by biomass (in %) in the Lunsky Bay in January 1998

6.9.2. Secondary commercial and perspective for fishery species

Sakhalin char In July 2000, Sakhalin char occurred along the eastern shore of the bay (Latkovskaya et al., 2002). Fish lengths varied from 14,1 to 75,0 cm, weight from 31,9 to 5435,0 g. Specimens 13,0-17,0 cm long, and 50-100 g and from 2 to 6 kg weigh were dominants by abundance (Fig. 6.9.8, 6.9.9). Fish at II-III stages of maturity prevailed.

213

30

20 % 10

0 12 16 20 24 28 32 44 48 52 56 60 64 68 72 76 Длина, см

Fig. 6.9.8. Distribution of Sakhalin char by lengths AC in the Lunsky Bay in July 2000 (n = 33)

30

20 % 10

0 0 200 800 3000 6000 Масса, г

Fig. 6.9.9. Distribution of Sakhalin char by body weights in the Lunsky Bay in July 2000 (n=33)

Pond smelts Fish from 6,0 to 18,0 cm length occurred in our catches (Latkovskaya et al., 2002). Two size groups dominated by abundance: 7,0-8,0 cm and 14,0-15,0 cm long (Fig. 6.9.10).

40,0 35,0 30,0 25,0 % 20,0 15,0 10,0 5,0 0,0 55 65 75 85 95 105 115 125 135 145 155 165 175 Длина АС, мм

Fig. 6.9.10. Distribution of pond smelts by lengths AC in the Lunsky Bay in July 2000 (n = 510)

Big-scaled redfin This species occurred in catches at major ichthyological stations. Both juvenile big-scaled redfin to 17,1 cm long, and adult specimens from 30,5 to 33,9 cm long were found in catches (Fig. 6.9.11). 214

40

35

30

25

20 %

15

10

5

0 10 12 14 16 18 20 22 24 26 28 30 32 34 Длина АD, см

Fig. 6.9.11. Distribution of big-scaled redfin by lengths AD in the Lunsky Bay in July 2000 (n = 30)

Pacific eelpout This species occurred in small numbers along the eastern shore of the bay. A total of 14 specimens from 8,1 to 35,6 cm long, averaged 23,0 cm were caught during all the study period. Females at II and III stages of maturity prevailed in catches.

Starry flounder This species occurred at major ichthyological stations over the bay. Both juveniles and adult fish from 5,0 to 38,0 cm long and from several to 500 g weigh were found. Immature fish formed the base of catches. Specimens from 5,0 to 17,0 cm long and to 200 g weigh at the age to 3+ dominated by abundance (Fig. 6.9.12, 6.9.13).

35 30 25 20 % 15 10 5 0 50 80 110 140 170 200 230 260 290 320 350 380 Длина, см

Fig. 6.9.12. Distribution of starry flounder by lengths AD in the Lunsky Bay in July 2000 (n = 158)

215

25

20

15 % 10

5

0 20 30 40 50 100 200 300 400 500 1000 1500 2000 Масса, г

Fig. 6.9.13. Distribution of starry flounder by body weights in the Lunsky Bay in July 2000 (n = 80)

Banded flounder This species occurred in catches only in the northeastern part of the bay. Fish from 8,0 to 24,0 cm long and from 10 to 300 g weigh were found (Fig. 6.9.14, 6.9.15). Specimens to 10,0 cm long and to 30 g weigh at the age to 4+ prevailed by abundance (Fig. 6.9.16). Majority of fish were at I and II stages of maturity. Maturating females occurred sporadically.

60

40 % 20

0 6 8 10 12 14 16 18 20 22 24 Длина, см

Fig. 6.9.14. Distribution of banded flounder by lengths AD in the Lunsky Bay in July 2000 (n = 163)

14,0 12,0 10,0 8,0 % 6,0 4,0 2,0 0,0 50 80 110 140 170 200 230 260 290 320 350 380 Масса, г

Fig. 6.9.15. Distribution of banded flounder by body weights in the Lunsky Bay in July 2000 (n = 163)

216

50 40 30 % 20 10 0 1+ 2+ 3+ 4+ Возраст, лет

Fig. 6.9.16. Distribution of banded flounder by age groups in the Lunsky Bay in July 2000 (n = 21)

Asiatic smelt is the object for amateur fishery in the bay in winter period. This species, evidently, enters the bay for feeding from the other regions of reproduction.

6.9.3. Mass non-commercial species

Threespine stickleback This species was the dominant by frequency during the study period (Latkovskaya et al., 2002). Analysis of the mass material (2507 ind.)showed that females prevailed by abundance (73,3%). Perhaps, males mature under the less sizes and age. Evidently, females dominate by numbers in the elder age groups, and some part of male eliminate. Fish of 5,5 to 9,0 cm long were found. Specimens 6,0-8,0 cm long prevailed by abundance (Fig. 6.9.17).

40

35

30

25

20 %

15

10

5

0 5,5 6,0 6,5 7,0 7,5 8,0 8,5 9,0 Длина AD, см

Fig. 6.9.17. Frequent distribution of threespine stickleback by lengths AD in the Lunsky Bay in July 2000 (n = 2507)

Ninespine stickleback This species occurred in the mouth of Kiri River in small numbers (Latkovskaya et al., 2002). Fish lengths varied from 3,5 to 7,0 cm. Specimens 45 – 65 mm long prevailed by abundance (86,3 %) (Fig. 6.9.18).

217

30

25

20

15 %

10

5

0 3,5 4,0 4,5 5,0 5,5 6,0 6,5 7,0 Длина AD, см

Fig. 6.9.18. Frequent distribution of ninespine stickleback by lengths AD in the Lunsky Bay in July 2000 (n = 117)

Thus, the Lunsky Bay is the least commercially important among all the considered bays of northeastern Sakhalin. First, commercial fish do not form there dense aggregations. Second, there is a great remoteness of this water body from the localities and the absence of good routes leading to it. Saffron cod and flathead sculpin are being caught in winter in small numbers using trap nets. During their fishing, banded flounder and smelts occur as a bycatch. A relatively poor species composition of ichthyofauna has been noted in the bay. For the first turn, to our mind, this is explained by the absence of large water courses in the basin, which are necessary for reproduction of many anadromous species. Mainly, anadromous fishes, which spawn in basins of the other bays, feed in Lunsky Bay. Juvenile starry flounder, which is very abundant on the northeastern Sakhalin shelf, feed in the bay. Species from the family Gasterosteidae have the greatest abundance and biomass in the bay.

218 7. COMPARATIVE CHARACTERISTIC OF BAYS

7.1. General physic-geographic characteristics

In accordance with classification of P.F. Brovko (Brovko, 1990), the bays of the northeastern Sakhalin coast are related to the class of coastal lagoons. The bays Nabil and Piltun are common lagoons by their types, and the bays Chaivo and Nyisky lagoon-estuaries. The first type of lagoons is characterized by the occurrence of the relatively long, deep, and narrow channel transforming into a short fairway, and wide shallow basin of a bay with the even bottom relief. For the second type of lagoons, the occurrence of short channels and fairways significant by their lengths is inherent. A basin of lagoon-estuaries is narrower, and it is crossed by the erosive narrows, in fact, being a continuation of river-beds flowing into a bay. By the level of their isolation from a sea, the bays Nabil and Piltun are related to the subtype of semi-closed lagoons, and the bays Nyisky and Chaivo are semi-open lagoons. By their areas, the bays are ordered in the following way: Piltun - 435.0 km2, Nabil - 187.8 km2, Chaivo - 126.4 km2, Nyisky - 110.9 km2. The prevailing depths in the bays are as follows: Piltun - 2-3 m, Chaivo - 1.5-2.3 m, Nyisky - 0.8-2.5 m, Nabil - 0.8-2 m. A hydrologic regime of the coastal bays is determined by the penetration of seawaters through the channels, and terrigenous run-off on the periphery. In the near-strait part the tidal fluctuations of a sea level affect greatly the formation of the lagoon hydrodynamics regime. In the study region the tides have a daily character. The mean values of tides increase from south to north from 0.7 m at the inlet to the Nabil Bay to 1.0 m at the inlet to the Piltun Bay. Respectively, the maximum amplitude of tidal fluctuations increases from 1.8 m at the inlet to the Nabil Bay to 2.3 m at the inlet to the Piltun Bay. A penetration of the tidal wave into lagoons is accompanied by the occurrence of strong tidal currents of a stream character. These currents reach the maximum estimates in channels and on the main fairway. The mean velocities of periodical currents in the channel region make up 0.4-0.8 m/s, and maximum may exceed 2.0 m/s. Besides the tide phenomena, a sea influence upon the hydrodynamics regime of the coastal bays becomes apparent under stormy raisings of the water level. The strongest raisings are observed in October-November and February-March during the passing of deep cyclones. In this period the estimates of level raising may reach 0.5- 1.0 m, the reiteration of raisings (more than 0.5 m) makes up 4 cases a year. During the raisings, a great volume of seawater enters the bay under the influence of pressure winds. After the wind cessation or its weakening, the accumulated water mass flows out of the bay to the sea carrying away solid material. In the bay channels the effect of raisings is usually strengthened by the influence of a heavy sea. The influence of river run-off upon the hydrologic regime of the bays becomes apparent, mainly, on their periphery in places of the large rivers’ inflow. Such influence is the most evident in the southern part of the Nyisky Bay, the place of the Tym River’s inflow. A mean annual volume of water carried out by the river constitutes more than 2.6 billion m3 a year, a mean annual sediment run-off more than 200 thousand tons. The rivers flowing into the other bays are smaller than the Tym River, nevertheless, the annual volumes of run-off are rather significant for the largest rivers: r. Dagi - 345 million m3/year, r. Val - 720 million m3/year, r. Piltun - 250 million m3/year. The volumes of sediment run-off constitute 7.6 thousand t/year for the Dagi River. During a spring flood, 30-40 % (in Tym River to 60 %) of river annual run-off and to 60 % of sediment annual run-off enter the bays. A spring flood causes a raise of water level in the largest rivers up to 1.0-2.7 m. A temperature regime of lagoons of the northeastern Sakhalin coast is determined by the entrance of seawaters through the channels, radiation warming, and in-shore run-off. In the summer period the lowest water temperatures are recorded in the deep near-strait parts of the bays, where a thermal regime is formed under the influence of cold seawaters. In the semi-closed lagoons Nabil and Piltun a vertical structure of the temperature field is characterized by the

СахНИРО Отчет по договору Y-00571 219 occurrence of temperature contrasts only in the channel region. On the rest area of the bays the differences between water temperatures at the surface and near the bottom do not exceed 1-3 °С. In the bays Nyisky and Chaivo a vertical temperature distribution in the summer period is characterized by the great contrasts reaching 5-12 °С, due to the seawater penetration along the fairways practically all over the bay area. A salinity regime of the coastal lagoons is formed under the influence of sea tides and river run-off. In the bays Nabil and Piltun the water with salinity 20 ‰ and more is recorded only in the channel and close to it. Directly in the lagoons, salinity declines rapidly; its estimates do not exceed 4-10 ‰ on the major area of Nabil Bay, and 2-6 ‰ in the Piltun Bay. In the bays Nyisky and Chaivo the water with salinity 20 ‰ and more in the surface layer occupies all the central part of the area. In the near-bottom layer, seawaters penetrate along the fairways practically all over the lagoon area (Ecological studies …, 2001).

7.2. Hydrochemical parameters

Characteristics of hydrochemical parameters of the northeastern Sakhalin bays by the materials of summarized data of the June-September 1995-2002 surveys are given in Table 7.2.1.

Table 7.2.1 A range of hydrochemical parameter changes for the northeastern Sakhalin bays in June- September 1995-2002 (in brackets – single extreme results) Ingredients, A range of concentrations units of measure Piltun Chaivo Nyisky Nabil Lunsky рН 5.40 – 9.04 7.49 – 8.74 7.67 – 8.69 6.68 – 9.17 7.62 – 9.05 Dissolved oxygen, mg/dm3 7.60 – 11.10 8.50 – 11.00 7.60 – 12.96 6.28 – 11.60 8.63 – 16.73 Nitrogen nitrite, 0.00 – 11.20 0.00 – 7.86 0.0 – 37.0 0.0 – 14.4 0.0 – 1.2 mkg/dm3 Nitrogen nitrate, 0.00 – 10.81 0.00 – 9.00 0.0 - 60.8 0.0 – 25.4 0.00 – 38.57 mkg/dm3 Nitrogen ammonium, 0.00 – - 1.47 – 14.25 3.38 – 36.26 0.0 – 135.0 mkg/dm3 104.39 Phosphorus general, 15.0 – 215.0 - 7.50 – 82.50 34.0 – 300.5 23.1 – 76.20 mkg/dm3 Phosphorus organic, 3.0 – 82.0 - 15.0 – 16.0 0.0 – 86.0 - mkg/dm3 Phosphorus mineral, 1.5 – 110.2 12.0 – 76.5 15.0 – 75.3 1.0 – 298.2 23.1 – 75.0 mkg/dm3 Silicon, 264.0 – 480.5 – 700.0 – 203.5 – 163.0 – mkg/dm3 7700.0 1699.0 8050.0 3990.0 2700.0 BOD5, 2.79 – 6.21 - 0.93 – 4.82 0.28 – 4.14 1.49 – 3.10 mg/dm3 (12.59) Permanganate oxidation, 7.62 – 14.85 - 1.70 – 7.14 5.74 – 11.8 - 3 mgО2/dm Suspended matter, mg/dm3 2.5 – 105.0 10.45 – 7.8 – 171.3 2.35 – 79.81 4.20 – 56.20 49.70 Petroleum products, <0.005 <0.005 <0.005 0.006 – 0.03 0.005 – mg/dm3 0.009 Chlorophyll a, 1.00 – 8.02 1.84 – 4.22 0.93 – 12.33 0.58 – 15.32 0.35 – 8.52 mkg/dm3 * the data scatter by years is insignificant that allow summarizing the estimates of hydrochemical ingredients and chlorophyll a

СахНИРО Отчет по договору Y-00571 220 This Table shows that a significantly greater scatter of pH values is common for the bays Piltun, Nabil, and Lunsky compared to Chaivo and Nyisky. This is connected with the fact that in the first case the seawaters exert the maximum influence upon pH values in the near-strait part, whereas in the rest part the terrigenous run-off, stagnant phenomena, and intensive phytoplankton development affect stronger. For the more open bays Chaivo and Nyisky, a gradient of pH values is not very significant. Concentrations of dissolved oxygen and a range of changes for all the bays, except Lunsky, are close by values. The attention is attracted by a comparatively high level of content of dissolved oxygen in the Lunsky Bay water, where the maximum estimates have been recorded in places of the thermal sources outflow. It should be noted that concentrations of dissolved oxygen in the water was high enough for all the bays. A great scatter of concentrations is common for the biogenic element distribution: from almost a full absence (below a threshold of the method detectability) to the rather high values; this is a sequence of unevenness of biological and chemical processes in different parts of the bays (channel, mouth sites, stagnant zones etc.). A comparison of the obtained data shows that concentrations of the major biogenic elements are somewhat lower in the Lunsky Bay water, which can be a sequence of the lesser productivity of the water body. Estimates of biochemical oxygen demand are rather high for all the bays and connected, evidently, with the abundance of organic matters of the natural origin and intensive biochemical processes. According to the accepted classification (Alekin O.A., 1970; Hydrochemical indices…, 1999) and using the following parameters: BOD5, permanganate oxidation, and concentration of suspended matters, the waters of the northeastern Sakhalin bays can be related in such a way as for a class and category of water quality: Lunsky Bay - to the weakly polluted, excluding the places of the thermal sources outflow; Nyisky and Nabil – moderately polluted; Piltun – polluted. A comparison of the tolerance limited concentrations (A list of fisheries standards…, 1999) BOD5 with BODcomplete proves a rather high pollution of the bays with organic matters. However, the waters of the northeastern Sakhalin bays are mostly pure and pure by the content of biogenic elements according to the same classification. Petroleum hydrocarbons had been found very rare in the bay waters and were of the trace character; in major cases a content of petroleum products was below a threshold of the method detectability. On the whole, the Piltun Bay is somewhat distinguished by the level of content of the organic matter in water. Although the occurrence of petroleum products was recorded in the bays Nabil and Lunsky, but their concentrations had a trace character. A range of change of the chlorophyll a concentration was minimum in the Chaivo Bay, and maximum in the bays Nyisky and Nabil. Perhaps, the levels of content and scatter of estimates are a consequence of different intensity of phytoplankton development.

7.3. Particle-size composition of bottom sediments

A composition of bottom sediments of the northeastern Sakhalin bays and their distribution by fractions are in concordance with the distribution pattern of the hydrodynamics active zones. A particle-size composition of the bays Piltun and Nyisky is presented by all types of grounds: from graveled sand to loamy silts; 6 main compounds of fractions are distinguished for the bays Chaivo and Nabil; 5 prevailing types of grounds are distinguished for the Lunsky Bay. A distribution character of size fractions is similar for all the bays. The highest content of coarse fractions (coarse-fragmental and sand) is observed at the inlets of the bays, along the spits, and in the river mouths. In channels and on the fairways of all the bays the bottom sediments are represented, mainly, by the well-sorted medium and fine sands. A bottom of the bay basins is formed, mainly, by pelites, poor-sorted sediments of fine sand and aleurites. The sands of different size constitute 20 - 55 % of the sample composition. The occurrence of needles of various tree types was recorded in bottom sediments of the Lunsky Bay almost everywhere.

СахНИРО Отчет по договору Y-00571 221 A division of area into two well expressed parts (one occurring under the influence of sea tides, and another exposed to the influence of the river run-off) is common for the bays Nabil and Piltun. There is not any clearly expressed border for the rest bays; a distribution of bottom sediments is caused by the complex hydrodynamics conditions.

7.4. Pollutants

Petroleum hydrocarbons in bottom sediments A range of petroleum hydrocarbon concentrations in the bays’ bottom sediments by years is given in Table 7.4.1.

Table 7.4.1 A range of the summarized petroleum hydrocarbon concentrations in bottom sediments of the northeastern Sakhalin bays in June-September 1995-2002 Bay Concentration of petroleum hydrocarbons, mkg/g 1995 1996 1999 2000 2002 June June August June-July July September Piltun - - 60.0-510.0 0.0-1.7 - 0.74-22.3 Chaivo - 70.0-120.0 10.0-50.0 0.0-0.5 - 0.95-26.5 Nyisky 0.3-17.3 60.0-390.0 50.0-500.0 0.00-16.08 - <0.5-41.1 Nabil - 100.0-1600.0 60.0-900.0 0.0-0.2 - 0.66-21.7 Lunsky - - - - 0.5-129.0 0.0-7.87

The presented data show that a significant scatter of concentration values is common for the bays both between the extreme points of the range and due to the study year. In general, the obtained data show the bays Nyisky and Chaivo to be the most polluted by the content of petroleum hydrocarbons in bottom sediments. The summarized estimates of petroleum hydrocarbon concentrations in bottom sediments of the rest bays are approximately at the same level. They are (by the data of 1999 – 2002) below or comparative with those in bottom sediments of the northeastern Sakhalin shelf (60.0 – 70.0 mkg/g, on average) (Nemirovskaya I.A., 1997) and significantly lower the level of PHC accumulation in the polluted regions (up to 39000 mkg/g). When distributing over the area, the higher levels of PHC accumulation in silty grounds along the fairway, in stagnant zones, and near the river mouths are common for all the bays. Phenols in bottom sediments Table 7.4.2 shows the contents of phenols in the bays’ bottom sediments by single data of June 1996. Table 7.4.2 Phenol contents in bottom sediments of the northeastern Sakhalin bays Bay Concentration, mkg/g Piltun 0.038 Chaivo 2.90 Nyisky 2.96 Nabil 2.21

The Piltun Bay is the purest by phenol contents. A comparison of levels of phenol contents in June 1996 with those in 1990 – 1991 (Krasavtsev, 1991) and with phenol concentrations in background regions of the northern Pacific Ocean (Tkalin et al., 1991) has shown the increase in contents compared to 1990-1991, and the excess of background concentrations, which is connected with the processes of phenol accumulation in bottom sediments due to their inflow from different sources.

СахНИРО Отчет по договору Y-00571 222 Chlororganic pesticides in bottom sediments Table 7.4.3 shows the mean contents of pesticides in bottom sediments by the data of studies of the northeastern Sakhalin bays in 1996 and 1999.

Table 7.4.3 Mean summarized concentrations of chlororganic pesticides in bottom sediments of the northeastern Sakhalin bays in 1996 and 1999 Bay Concentrations of chlororganic pesticides, ng/g 1996 1999 June August June-July Piltun - 0.13 0.14 Chaivo 0.72 0.13 1.20 Nyisky 0.38 0.013 1.05 Nabil 0.73 0.05 0.89

By the obtained data, the Piltun Bay is the purest by the content of chlororganic pesticides. In the rest bays the levels of COP accumulation in bottom sediments are close by values. COP have not been studied in the Lunsky Bay bottom sediments. A comparison of COP concentrations in the bays’ bottom sediments with those from the literary sources (Tkalin et al., 1991; Background monitoring of pollution…, 1990) for the studied non-polluted regions shows a rather low level of pollution for the bays’ bottom sediments, although indicates the existing source of COP inflow and accumulation in silty grounds of the bays. A comparison of COP concentrations in bottom sediments of the nearest Sakhalin shelf shallow site with those in the bays (Scientific report, 2001) shows significantly high concentrations in the bays and proves their important role in the water purification from dissolved and suspended forms of pollutants.

Organic carbon in bottom sediments Table 7.4.4. shows a range and mean concentrations of organic carbon in the bays’ bottom sediments.

Table 7.4.4 A range and mean concentrations of organic carbon by the data of studies in June-July 1999 Bay Concentration, % 1999 mean range Piltun 0.9 0.0 – 5.3 Chaivo 2.9 0.0 – 10.0 Nyisky 2.1 0.0 – 6.6 Nabil 2.0 0.0 – 6.6

The greatest scatter of estimates of the organic carbon concentrations is observed in the Chaivo Bay. In the Piltun Bay the mean content is minimal. In the rest bays the mean content of organic carbon in bottom sediments is at one and the same level. The Lunsky Bay has not been studied for Сorganic in bottom sediments.

Metals in bottom sediments A range of changes in concentrations of the metal acid-dissolved forms in the northeastern Sakhalin bays by materials of the summarized data of study in June-September 1995 – 2002 is given in Table 7.4.5.

СахНИРО Отчет по договору Y-00571 223 Table 7.4.5 A range of changes (or single concentration) of the metal acid-dissolved forms in the northeastern Sakhalin bays in June-September 1995 – 2002 Ingredients A range of concentrations, mkg/g Piltun Chaivo Nyisky Nabil Lunsky Fe 4748 300-20500 8131-10650 2825-6520 6839 Al 2572 2800-7403 5751-6385 1425-4996 15490 Mn 38.2-118.0 35.0-78.0 69.7-156.0 12.3-110.0 Zn 15.3-16.6 6.5-40.0 26.8-40.3 6.1-33.8 36.6 Cr 14.6-127.3 3.0-57.8 12.6-55.0 7.0-65.5 16.1 Ni 13.5-38.5 4.08-42.0 8.4-41.7 2.6-40.0 12.7 Cu 4.44-17.20 2.4-19.0 5.0-22.2 0.6-20.9 10.5 Co 1.56-2.95 1.7-3.8 2.9-3.9 2.2-3.1 4.64 Pb 1.79-15.2 2.8-19.5 2.9-18.5 0.9-16.5 9.9 Cd 0.17 <0.05 0.06-0.09 0.04-0.06 0.208 Hg 0.009 0.015 0.010-0.034 0.011-0.018 0.042 Ba 592 - 67-584 111-612 46.6 V 11.6 10.5 20.0-36.5 - 29.5

Among the northeastern Sakhalin bays, the Lunsky Bay is distinguished by the content of active forms of Al, Cd, Hg in bottom sediments. The relatively high levels of cadmium content may be a sequence of the upwelling affect; mercury – the outflow of thermal waters; aluminium – the geochemical peculiarities of water collections, shores and bottom of the bay (Scientific report, 2002). A great range of changes in iron concentrations for the Chaivo Bay attracts attention; this may also be consequence of geochemical peculiarities. Concentrations of the rest elements are close in all the bays due to the common geochemical background of northeastern Sakhalin. A comparison of concentrations of the metal acid-dissolved forms in the bay bottom sediments with grounds of the more urbanizated regions (Tkalin et al., 1997; Shulkin et al., 1989) has shown a significantly lower level (except for cadmium). The obtained levels have been formed by the natural factors, and they can be accepted as background.

Metals in biota By their levels of accumulation in Zostera, metals of the bays Chaivo, Nyisky, and Nabil can be ordered in such a way: Zn > Cr > Cu > Cd > Pb > Hg. The higher level of microelement accumulation in Zostera of the Chaivo Bay attracts attention. A small volume of the study materials does not allow a detail comparative characteristic of the bays. The data on metals in fish tissues, chlororganic pesticides and hydrocarbons in Zostera are scanty, have not any systematic character, and require further surveys.

7.5. Microbe indication

Summarizing the results of study of the bays’ microflora, the active communities of heterotrophic water and bottom sediment microorganisms can be reported in each of the bays. A structure of communities is formed by the various ecologic-trophic groups of microorganisms. Microorganism abundance is the main index, by which the contribution of each group into the community structure can be estimated, and the main processes occurring in the water body can be characterized. Saprophyte heterotrophic water bacteria taking part in the decomposition of handy organic compounds (determined on RPA) were presented in the bays in the summer-autumn period by the abundance of 102 to 106 cell/ml. A seasonal dynamics of abundance variation for this group is watched clear enough. The abundance of hundreds to several tens of thousands of cells per 1 ml had been recorded in the first summer months in the bays Nyisky (1999) and

СахНИРО Отчет по договору Y-00571 224 Lunsky (2000), when the rather low water temperatures supressing the development of microorganisms prevailed. The increase in saprophyte abundance took place by the end of summer – beginning of autumn and constituted from several thousands to billion of cells per 1 ml in the bays Nyisky (1996, 1998), Chaivo (1998), and Nabil (1998). Water temperatures optimal for development, and contents of organic matters accumulated due to the vital activity of all links of the trophic chain promoted the high abundance of saprophyte heterotrophic microorganisms in August-September. Regarding to marine heterotrophic microorganisms developing under the changing regime of salinity in the bays, the situation was analogous. In early summer the abundance of this group in the bays Nyisky (1999, 2000) and Lunsky (2000) was within 102 – 104 cell/ml. The maximum estimates of abundance were recorded in late August in the Nyisky Bay (1996) and in early September in the bays Nyisky, Chaivo, and Nabil (1998), and constituted 106 - 107 cell/ml. The abundance indices of saprophyte microflora of the marine heterotrophic microorganisms from bottom sediments were one-two orders of magnitude higher compared to those from the water. Thus, in the Nyisky Bay (2000) they constituted 103 - 105 cell/g, in the Lunsky Bay (2000) – 104 cell/g. A normal functioning of the total water body community, and microbe in particular, is supported by the activity of microorganisms from different physiologic groups. Taking part in decomposition of polysacharides, carbohydrates, protein, peptides, organic acids, and aminoacids being secreted during the dying of live organisms (phyto- and zooplankton, algae, macrophytes, invertebrates and others), different physiologic active groups realize a process of purification of the water body. The activity of proteolytic, amylolytic, and lipolytic bacteria, as well as the other indicator groups is determined by their numbers. The abundance of the above groups was determined not in all the bays. In the Nyisky Bay in 1998, a proportion of proteolytic microorganisms constituted from 1.3 to 13.95% of the total abundance of heterotrophic microorganisms, in 2000 – from 2.5 to 86.9%. The relative abundance of this group in 1998 was within 0.91 – 21.25%, in the Nabil Bay 3.2 – 23.4%. In the Lunsky Bay it was 27.3% in 2000, in the Piltun Bay - 28% in 1999. Amylolytic and lipolytic microorganisms from the bays’ water were physiologically active too. In 1998, lipolytic microorganisms constituted to 27.3 % of the total abundance of heterotrophic microorganisms in the Nyisky Bay, to 12.2% in the Chaivo Bay, and to 33.3% in the Nabil Bay. The vast macrophyte fields in the bays caused the activity of amylolytic microorganisms, which relative abundance varied from 2.5 to 74.4% by the bays. As the conducted studies have shown, phenol-resistant microorganisms make up a great portion of heterotrophic microbe community of the bays. The estimates of abundance of this group in the studied bays were similar, on average, and constituted from 102 to 104 cell/ml. A chemical analysis of grounds in the bays showed a background content of phenols of the anthropogenic origin. The occurrence of phenol-resistant microorganisms in the bays, most probably, is caused by the phenol compounds, which are being formed under the microbiological destruction and transformation of various organic compounds being formed during the process of vital activity of the all community of water body (Kondratyeva et al., 1998; Saralov et al.,1979). The high concentrations of phenol compounds, being not connected with the sewage discharge, may also be found in water under releasing the low-molecular aromatic compounds during destruction of the vegetative lignin-containing substrates, the providers of which are vast macrophyte thicket in the bays. Hydrocarbon-oxidizing microorganisms are widely distributed in different areas of the World Ocean and are the common components of marine ecosystems (Mironov, 1971; Gusev, 1980; Coronelli et al., 1987). This group of microorganisms is used as indicators when revealing pollution of water objects with hydrocarbons. However, some researchers indicate the fact that the strictly obligated petroleum-oxidizing microorganisms have not still ascertained, and think that the occurrence of this group of microorganisms does not prove the oil presence in the environment, and this is explained by the vast abilities of the bacteria fermentative organs (Salmanov, 1999). Some authors (Mishustina, 1985) advise to interpret the obtained data on hydrocarbon-oxidizing microorganisms for the coastal waters and open regions with caution, and

СахНИРО Отчет по договору Y-00571 225 to use along with that the data of chemical analysis. Hydrocarbon-oxidizing microorganisms occurred in all the studied bays. The minimum number of this group (102 cell/ml)was recorded in the Nyisky Bay in 2000 and at some stations of this bay in 1996 and 1999. The high indices of abundance were recorded in 1998 in the bays Nabil, Chaivo, and Nyisky. The numbers reached 106 – 107 cell/ml. The abundance indices for sanitary-indicator microorganisms are used, along with indices of the heterotrophic group numbers, during the estimation of the natural water quality; they are indicators of anthropogenic industrial-domestic impact on the marine environment, and indicate a biological pollution. Bacteria of the group of enteric bacillus (BGEB) and some groups of pathogenic enteric bacteria (PEB) are the most recognizable and distributed all over the world sanitary-indicative microorganisms (GOST, 1977; Zhukinsky et al., 1981). No sanitary-indicative microorganisms being indicators of biological pollution were found in the analyzed water and ground samples of the Lunsky Bay. The higher content of indicator organisms in the bays Nyisky and Chaivo was found in samples, which were collected at sites located along the line off the settlements, nearby the fishing camps, and in the mouth zones of rivers, and indexed a new inflow of organic matters of the anthropogenic origin. A comparative analysis and interpretation of the obtained results on the metal-resistant microorganisms is difficult by the fact that one and the same metals can be indices of different processes for the bays on one hand, and that the used method of microbe indication has been at a stage of modification, and the obtained results should give the reply on the possibility of its application in the conditions of northeastern Sakhalin lagoons on the other hand. In general, the obtained data give an idea of the content of metals in the bays. Thus, the microbe indication revealed the occurrence of iron belonging to the metals-markers of terrigenous run-off. A high percentage of these forms in the bays’ waters (to 98%) can be also caused by peat grounds containing a significant number of iron. The numbers of zinc-, lead-, copper-, and nickel- resistant forms of microorganisms were great in all the bays. A chemical analysis of bottom sediments showed the presence of all these metals in the bays. Nickel, lead, and cadmium are indicators of the man-caused pollution; copper and zinc – of anthropogenic impact. Nickel, copper, lead, and zinc are related to the ore-genic elements, and also enter the composition of Sakhalin oils. A number of cadmium-resistant microorganisms was significantly lower in all the bays. Cadmium has the lowest concentration among the found metals by the data of chemical analysis of the grounds too.

7.6. Phytoplankton of the bays

By the results of studies, a total of 338 species and intraspecific taxons of microalgae have been found; 47 of them were common for all the bays of northeastern Sakhalin. A leading place in formation of species composition was occupied by diatom algae, which greatest diversity was recorded in the Nyisky Bay (142 species and intraspecific taxons). In the phytogeographic respect, cosmopolites (25-40 %) and boreal (19-40 %) species prevailed, and in the bays Lunsky and Nyisky the tropical-boreal species (13-19 %) prevailed along with cosmopolites and boreal ones. A significant development of freshwater forms was observed in the bays with the weakly expressed tide phenomena (Piltun and Nabil bays), whereas the predominant development of marine forms was limited by the channels flowing into the main body of these lagoons. In contrast, in the bays Nyisky, Chaivo, and Lunsky, marine species were distributed everywhere, and the greatest development of freshwater forms was observed at the near-mouth sites. The maximum abundance (746,646 thousand cell/l), due to the development of colonial bluegreen and green algae, was recorded in the Piltun Bay, biomass (474,43 mg/m3) – in the Lunsky Bay. The Chaivo Bay was characterized by the minimum estimates of quantitative indices ( there the abundance was 75 thousand cell/l, and biomass 152,23 mg/m3).

СахНИРО Отчет по договору Y-00571 226 Cryptophyte and diatom algae made the main contribution into the abundance formation in all the bays, except for Piltun Bay, where green and bluegreen algae dominated by numbers. Mainly, diatoms prevailed by biomass.

7.7. Zooplankton of the bays

A total of 33 species and forms of organisms from 10 groups have been found from samples. Due to the relatively small depth of the bays, a high number of the near-bottom forms were recorded in samples. Two forms of 33 are facultative-planktonic, that is, related to planktobenthos (harpacticides, hydracarines), 6 – meroplanktonic (planktonic stages of benthic and parasitic animals). Major species are related to brackish and euryhaline (Sinocalanus tenellus, Shmackeria inopina). Freshwater species enduring salinization (Chydorus sp.) occur at the more freshened sites, and at sites with greater salinity – marine coastal species enduring freshening (Acartia hudsonica, Pseudocalanus neumani, Podon leucarti). A group of copepods (18 forms) is the richest both in the quantitative and qualitative respects, which is represented in the bays by 3 suborders: Calanoida and Cyclopoida (typical plankters) and Harpacticoida (planktobenthos). Zooplankton of the Chaivo Bay completely consists of copepods. They all are important food organisms and make up the base of feeding for the bays’ fish-planktonophagans. Females of major copepods have spermatophores or egg sacs, and the number of nauplii is also high; this allows reporting the period of mass copepod development in the study period. The abundant cladoceres (Evadne nordmani, Podon leuckarty) and rotifers (Synchaeta sp., Euchlanis lucksiana) should be related to the important food organisms of the bays. The importance of the latter is especially great in the feeding of young fish-planktonophagans. Acartia hudsonica and Oithona similis appeared to be common species for all the bays, that is, marine coastal species freely penetrating into the bays. Zooplankton is distributed unevenly over the bays’ area. This is connected with some factors: a level of mineralization and water temperature, influence of the river and brook run-off and tides, uneven bottom relief, and vegetation development. A total of three main complexes common for the northeastern Sakhalin bays have been distinguished by the Shoener’s index. The maximum abundance (287526,8 ind./m3) was recorded in the Lunsky Bay (timed to the first complex), biomass (1899,64 mg/m3) in the Nyisky Bay (third complex). The mean abundance and biomass was higher in the Lunsky Bay (59006,2 ind./m3 and 328,20 mg/m3, respectively). The mean abundance was minimal in the Nyisky Bay (11878,3 ind./m3), and mean biomass in the Piltun Bay (137,85 mg/m3). In general, the mean abundance and biomass estimates are close in all the bays; their difference does not reach a threshold of the order.

7.8. Benthos

Communities Zostera and Macoma balthica make up the base of bottom communities in the bays Nabil and Nyisky, and on the major area of Chaivo Bay as well as in other high- boreal lagoon bays of the Northern Pacific (Haertel, Osterberg, 1967; Kafanov, Plekhov, 2001). Along with that, in contrast to the Piltun Bay where the macrobenthos communities occupy practically all the area (Labay et al., 1999, 2000), a distribution of bottom communities is extremely uneven in the bays, where the tidal affect is great (Chaivo and Nyisky bays). These differences are explained by the geomorphological peculiarities of each lagoon. Although all the described bays are related to one and the same type of semi-closed lagoons (Brovko, 1990), Piltun Bay and others differ significantly by the coefficients of water exchange, ratio of the water volume, being changed during the one tide-ebb cycle, to the total water volume in the lagoon. In contrast to the Piltun Bay being connected with the open sea by the long and narrow lagoon strait, the bays Chaivo, Nyisky, and Lunsky, and, to the less extent,

СахНИРО Отчет по договору Y-00571 227 Nabil have short and relatively wide lagoon straits. In addition, the Nyisky Bay is characterized by the annual summarized river run-off being more than 4 times greater (Bobrik, Brovko, 1987). As a result, salty and cold seawaters in the Piltun Bay are not distributed north of its central part during the tide, and occur, mainly, in the southwestern part of the bay. In the Nyisky Bay, seawaters with more than 28 ‰ salinity and less than 5 º С near-bottom temperature occupy almost all the lagoon under the tide, and during the ebb all the lagoon from surface to bottom is filled with water with less than 16 ‰ salinity and more than 10 ºС temperature (Polupanov, 1999). A more significant penetration of salty seawaters is common for the bays Chaivo and Lunsky. Differences in geomorphological peculiarities making up different habitat conditions for hydrobionts are reflected in the indices of species diversity characterizing the main macrobenthos communities in the bays (Fig. 7.8.1, 7.8.2, 7.8.3, 7.8.4).

3,37 Zostera j. 3,5 Potamogeton p. 3 2,55

2,5 Corbicula j. 1,64 2 1,22 1,31 Potamogeton p. 1,5 +Kamaka k. Вся лагуна 1

0,5

0

Fig. 7.8.1. Species diversity of the main macrobenthos communities in the Piltun Bay (along the ordinate axis – Shoener’s informational index of diversity)

3

2.5 Liocyma fluctuosa

2 Zostera var.

1.5 Chaetomorpha sp.

1 Macoma balthica + Zostera var.

0.5 Вся лагуна

0

Fig. 7.8.2. Species diversity of the main macrobenthos communities in the Chaivo Bay (along the ordinate axis – Shoener’s informational index of diversity)

СахНИРО Отчет по договору Y-00571 228

1,73 1,8 1,33 1,6 Zostera m. 1,16 1,4 Zostera j. 1,2

1 Macoma b. 0,8 0,52 0,6 Вся лагуна 0,4 0,2 0

Fig. 7.8.3. Species diversity of the main macrobenthos communities in the Nyisky Bay (along the ordinate axis – Shoener’s informational index of diversity)

3

2.5 Zostera var. 2 Macoma balthica + 1.5 Zostera var. Вся лагуна 1

0.5

0

Fig. 7.8.4. Species diversity of the main macrobenthos communities in the Nabil Bay (along the ordinate axis – Shoener’s informational index of diversity)

As one can see from the Figures, the index of species diversity for the Piltun Bay is higher compared to other bays. Communities of Zostera japonica recorded for all the bays are close by the index of species diversity. Their diversity indices constitute more than 1. The lowest index of diversity was observed for the community Zostera marina and Zostera var. in the bays Nyisky and Chaivo being under the constant influence of tidal currents. Z. marina is known to endure great temperature and salinity fluctuations (Kafanov, Lysenko, 1988). It prefers zones of the relative chalistasis in the upper-boreal Pacific lagoons (Kafanov, Plekhov, 1998), by which an irregular character of its distribution and low informational index of diversity in the bays Chaivo and Nyisky is explained. Due to the indicated

СахНИРО Отчет по договору Y-00571 229 geomorphologic and hydrologic differences, and a great number of estuarine sites in the bays Chaivo and Nyisky, significant numbers of different types of brackish communities and their variations have been observed. But no clear division of bottom communities for predominantly freshwater and brackish, as in the Piltun Bay (Labay et al., 2000), was observed. A wide distribution of the community Liocyma fluctuosa in the bays Chaivo and Lunsky is another important fact. As one can see from the above description, this community is localized in the places of the transformed coastal seawaters entrance into the bays, and it is their indicator. A vital distribution in the channels joining the bays with the sea has a zoning character, as it has been reported by Tabunkov et al. (1988). Such zoning is caused by the bottom topography and hydrodynamics regime. The borders between biocenoses localized at different horizons are clearly watched. The analogous biocenoses, except for the very low, occur in the Piltun Channel and Aslanbekov Strait at one and the same horizons. Thus, the communities with dominants Zostera and Macoma balthica characterizing the lagoon brackish waters themselves are common for all the bays; in the Piltun Bay with the constant zones of freshening, some intertransforming freshwater limnitic communities are observed; in the bays Chaivo and Lunsky in zones of penetration of the transformed seawaters, the community with dominant Liocyma fluctuosa is observed.

7.9. Ichthyofauna and fishery in the bays

Ichthyofauna in the northeastern Sakhalin bays is relatively young and composed of fish, which constantly live or spawn in different ecological conditions. Brackish water bodies are a secondary constant or temporary habitat for them. No doubts, the data on species composition of ichthyofauna will be replenished, for the first turn, due to the sea fishes episodically migrating from the sea to the bays and back. Evidently, some precise definitions will be in respect to individual lagoons. At the same time, in general, a list of anadromous and freshwater fishes in the bays, to our mind, will endure very little changes. At present, by the literary data and materials of our surveys, a total of 60 fish species from 26 families have been found in the northeastern Sakhalin bays (Table 7.9.1). On the whole, ichthyofauna of the considered bays has a rather similar character by species composition. At present, the most diverse ichthyofauna occurs in the bays Piltun, Chaivo, and Nyisky. Theoretically, the occurrence of marine species of the coastal complex being individually found in each of the bays is possible in all five bays: Osmeridae, Stihaeidae, Agonidae, Cottidae, and Pleuronectidae.

Table 7.9.1 Species composition of ichthyofauna in the northeastern Sakhalin bays (Zverkova et al., 1997; Labay et al., 1999; Latkovskaya et al., 2001, 2002, 2003; Safronov et al., 2003) Bay Families, species, and subspecies Piltun Chaivo Nyisky Nabil Lunsky PETROMYZONTIDAE Lethenteron japonicum – arctic + + + + + lamprey CLUPEIDAE **Clupea pallasiii - herring + + + + + ****Sardinops sagax melanosticta – + + ? ? ? west Pacific sardine ACIPENSERIDAE *Acipenser medirostris – Sakhalin ? ? ? - - sturgeon *Huso dauricus – kaluga sturgeon ? ? ? - -

СахНИРО Отчет по договору Y-00571 230 Bay Families, species, and subspecies Piltun Chaivo Nyisky Nabil Lunsky SALMONIDAE Oncorhynchus gorbuscha – pink + + + + + salmon Oncorhynchus keta – chum salmon + + + + + Oncorhynchus masou – masu salmon + + + + + Oncorhynchus kisutch – coho salmon + + + + + ***Salvelinus leucomaenis – + + + + + Sakhalin char *** Salvelinus malma + + + + + krascheninnikovi – southern malma *Parahucho perryi – Sakhalin + + + + + taimen COREGONIDAE Coregonus ussuriensis – Ussuri ++ + + - whitefish OSMERIDAE Mallotus villosus – capelin - + + - + Hypomesus japonicus – smelt - + + - - H. nipponensis – wakasagi + + + ? ? H. olidus – pond smelt + + + + + Osmerus mordax dentex – Asiatic + + + + + smelt ESOCIDAE Esox reichertii – Amur pike - - + - - SALANGIDAE Salangichthys microdon – icefish - - + - - CYPRINIDAE Carassius auratus gibelio – common + + + - - wild golfish Phoxinus perenurus – lake minnow + + + - - Rodeus sericeus – Amur bitterling + + + - - Leuciscus waleckii – Amur ide - - + - - ***Tribolodon brandtii – eastern + + + + + redfin (Brandt’s redfin) ***Tribolodon ezoe – Pacific redfin + + + + - ***Tribolodon hakuensis – big- + + + + + scaled redfin COBITIDAE Cobitis lutheri – loach + + + - - Misgurnus nikolsky – Nikolsky’s + + + - - loach BALITORIDAE Barbatula toni – Siberian stone loach + + + + - GADIDAE Gadus macrocephalus – Pacific cod + - - - - **Eleginus gracilis – saffron cod + + + + + MUGILIDAE Mugil cephalus – Pacific mullet + - - - -

СахНИРО Отчет по договору Y-00571 231 Bay Families, species, and subspecies Piltun Chaivo Nyisky Nabil Lunsky GASTEROSTEIDAE Gasterosteus aculeatus – threespine + + + + + stickleback Pungitius pungitius – (common) ++ + + - ninespine stickleback Pungitius sinensis – Amur + + + + + stickleback Pungitius tymensis – Sakhalin + + + - - stickleback STIHAEIDAE Opisthocentrus ocellatus – spottyfin + + + - - gunnel Pholidapus dybowskii – Dybowsky’s + + + - - blenny PHOLIDAE Rhodimenichthys dolichogaster – - + - - - stippled gunnel ZOARCIDAE Zoarces elongates – Pacific eelpout + + + + + HEXAGRAMMIDAE Hexagrammos octogrammus – - + + - + masked greenling Hexagrammos stelleri – whitespotted - + + - - greenling AGONIDAE Pallasina barbata – tubenose - + - - - poacher Brachyopsis segaliensis – long- + - - - + snouted poacher GOBIIDAE Chaenogobius urotaenia + + + - - COTTIDAE Cottus amblistomopsis – Sakhalin - - + - - sculpin Megalocottus platycephalus – + + + + + flathead sculpin Myoxocephalus jaok – plain sculpin + - + - - Myoxocephalus stelleri – Steller's + + - - - sculpin BLEPSIIDAE Blepsias cirrihosus – whiskered - - + - - sculpin HEMITRIPTERIDAE Hemitripterus villosus – raven- + - - - - sculpin CYCLOPTERIDAE Liparis kusnetzovi – Kuznetsov’s + - - - - snailfish AMMODYTIDAE

СахНИРО Отчет по договору Y-00571 232 Bay Families, species, and subspecies Piltun Chaivo Nyisky Nabil Lunsky Ammodytes hexapterus – Pacific + - - - - sand lance PLEURONECTIDAE Limanda aspera – yellowfin sole + + + - - Limanda proboscideus – snote sole + - - - - Limanda punctatissima – longsnout + - + - - flounder ***Platichthys stellatus – starry + + + + + flounder Liopsetta (Pleuronectes) ++ + + pinnifasciatus – banded flounder + Pleuronectes quadrituberculatus – + + + - - Alaska plaice * Rare, needing in protection, ** commercial, *** perspective for commercial fishing, ****fish species indicated for the previous years

Of the non-abundant species needing in protection (Red data book…, 2000), kaluga Huso dauricus and Sakhalin sturgeon Acipenser medirostris are known only from the answering information (Taranets, 1937б; Gritsenko et al., 1979; Gritsenko, 1990, 2002). Sakhalin taimen Parahucho perryi occurs in all the bays. It reaches the greatest abundance in the bays Nyisky, Chaivo, and Nabil. After migration downstream the rivers, adult taimen and their juveniles feed in the bays migrating periodically to the open part of the sea. Sakhalin taimen spawn in large rivers flowing into the bays Nyisky, Chaivo, and Nabil, and, to the less extent, in water courses flowing into the Piltun Bay. At the same time, this species feed in all five bays (Piltun, Chaivo, Nyisky, Nabil, and Lunsky). General regularities are observed in fish distribution over the bays’ area. Some species occur in the bays in definite periods. The representatives of anadromous species migrating relatively far to the sea: arctic lamprey Lethenteron japonicum, Pacific salmon Oncorhynchus, southern malma Salvelinus malma krascheninnikovi and others are observed in the bays only during the spawning and downstream migrations. Other species (Sakhalin taimen, Sakhalin char Salvelinus leucomaenis, Pacific redfins Tribolodon, pond smelts Hypomesus and others) feed in the bays for a long time, periodically coming into the open part of the sea. Freshwater species (Amur pike Esox reichertii, lake minnow Phoxinus perenurus, Amur ide Leuciscus waleckii, Amur bitterling Rodeus sericeus, and others) occur in the bays only at the limited strongly freshened sites, not far from the river mouths. Of marine fishes, only herring Clupea pallasii spawn in the bays. During a year, the feeding of adult fish and juveniles take place. Juvenile saffron cod Eleginus gracilis occur there in all the seasons. The mature specimens of this species, as a rule, occur in winter. Some of them (flathead sculpin Megalocottus platycephalus and banded flounder Liopsetta pinnifasciata) inhabit only the bays during a long period of time. Others (plain sculpin Myoxocephalus jaok, Steller’s sculpin Myoxocephalus stelleri, greenlings Hexagrammidae and others) are observed in the region of channels joining water bodies with the sea and adjoining sites of the bays with the high water salinity.

Fishery importance of the bays Fishing is conducted in the bays of lagoon type located in the northeastern Sakhalin from of old. Data on history of the bay fishery are taken from the literature and archive materials of SakhNIRO (Report …, 1956; Frolov, 1968а, 1969; Gritzenko, 1990, 2002; and others). Pacific salmon from the genus Oncorhynchus were the fishery objects in the pre-war and war years in this region. Their capture varied from 1,08 to 3,57 thousand tons since 1937 through 1943.

СахНИРО Отчет по договору Y-00571 233 Commercial fishing of salmon had been conducted, mainly, in the Nyisky Bay. Chum salmon Oncorhynchus keta were caught, predominantly, in its southern part, pink salmon O. gorbucha in the northern part. The main fishery was realized in August-September. In the following years, catches reduced greatly due to the irrational fishery (Table 7.9.2).

Table 7.9.2 Fish captures by the fishing enterprises in the northeastern Sakhalin bays in 1953-1956 (tons) Years Fish species 1953 1954 1955 1956 Pacific salmon 530 280 150 180 Herring 820 1440 1560 1470 Saffron cod 254,9 364,2 332,2 380,5 Flounders 88,4 179,1 271,8 235,1

To the late 1950s, an insignificant fishing was conducted in the mouths of Dagi, Evay, and Val rivers; in individual years chum salmon were captured in the mouth of Nabil River. A total of 6-7 beach seines were annually used in the Nyisky Bay during the fishery seasons. Since 1963, fixed nets began to be used, which number reached 10 units in 1965; their maximum number was 16 (1974). Since 1977, a limited chum salmon fishing had been enforced, when not only a size of capture, but also a number of gear was limited. The number of fixed nets was reduced up to 7 units in 1980 (Gritzenko, 1990; 2002). Pacific salmon Oncorhynchus Four species of 6 from the genus Oncorhynchus inhabit the northeastern Sakhalin coast: pink, chum, masu O. masou, and coho O. kisutch. At present, pink salmon (in odd years) prevail by numbers in the basins of all the considered bays. Chum salmon reach the maximum numbers in the basin of Nyisky Bay. Its largest spawning stock occurs in the basin of Tym River. Coho salmon occur in the basins of all the bays, and reach the maximum number in the basin of Tym River. This species makes up a bycatch during chum salmon fishing. Masu salmon is observed everywhere in all the bays’ basins, but it is not abundant. Masu juveniles are common in the major rivers flowing into the bays. Pacific salmon occur in the bays only during spawning run of the adult fish and downstream migration of their fry. Masu spawners appear first in the bays’ area, usually in mid – late May. Then mature pink salmon come in June-July. Chum salmon run for spawning through the bays into rivers in August-September. Coho spawners complete spawning run in October- November. Annually, during June-August, salmon fry migrating downstream the rivers to the sea pass through the bays’ area. Pink salmon. The Okhotsk Sea summer pink salmon population reproduces in the northeastern Sakhalin bays. In recent years, the short-period fluctuations of its numbers are clearly watched in the northeastern Sakhalin. On average, the abundance is greater in odd years. On the contrary, fry of the high-abundant generations migrate to the sea in even years. The terms of its mass spawning run to the rivers are from the third decade of July through the second decade of August. Pink sizes vary greatly. There are specimens with lengths from 28,0 to 68,0 cm, and weights from 400 to 2500 g, at 1+ age. The mean fecundity of pink salmon vary from 600 to 3000 eggs. A ration between sexes is close to 1:1. The pink fry migrants have a mean weight of 230-250 mg and length 30-35 mm. Its spawning occurs mainly in August-September. Fry migrate downstream the rivers to the bays since late May to early July, immediately after their emerging from the spawning grounds. Fry do not stay in the bays, and almost at once migrate to the sea along the fairways (Gritzenko et al., 1978; Gritzenko, 1990, 2002). Chum salmon. The autumn form of chum salmon spawns in rivers of the northeastern Sakhalin. A spawning run to the rivers takes place since late July through late October – mid- November. Chum approach to the river mouths along the fairways. The terms of spawning are shifted compared to those of run approximately two weeks. As a rule, a spawning begins in late

СахНИРО Отчет по договору Y-00571 234 August. The last spawning specimens may be found during all December. Fry migrate downstream the rivers to the bays in May-June. They migrate downstream the rivers to the sea immediately after their emerging from the spawning grounds. Fry pass the bay area along the fairways and float to the sea. The mean length of chum salmon varies from 67,0 to 74,0 cm, weight from 3,3 to 4,6 kg, absolute individual fecundity from 2900 to 3100 eggs. Specimens at 3+ and 4+ age make up the base of the spawning stock. The age group of 3+ is the dominant. A ratio between sexes is close to 1:1. Fry lengths vary from 27 to 54 mm (Gritzenko et al., 1978; Gritzenko, 1990, 2002). Coho salmon. By the terms of a spawning run, Sakhalin coho can be related to the autumn form. The spawning run begins in late August – early September, and finishes in early December. Fry’s downstream migration to the bays takes place in July-August. Soon, they migrate to the sea along the fairways. Coho sizes vary from 51,0 to 83,0 cm, weights from 2,1 to 7 kg. Their individual absolute fecundity vary from 1760 to 9010 eggs. The age group of 32 + prevails. A ratio between sexes is close to 1:1. Fry lengths vary from 9,5 to16,0 cm, weights from 15 to 34 g, age 1+ and 2+ (as a rule, specimens at 2+ age prevail by numbers) (Gritzenko, 1973; 1990; 2002; Zhulkov, 1978; Kovtun, 1995). Masu salmon. A spawning run of this species takes place since early June through early August. It spawns from the second half of July through early September. A downstream migration occurs in July-August. Masu lengths vary from 40,0 to 71,0 cm, weights from 0,8 to 3,8 kg. As a rule, fish are at 21 and 32 age. Females prevail among mature fish. Dwarf males never going to the sea are common in populations. Masu fry in rivers are common. Immediately after migrating from rivers to the bays, fry go to the sea along the fairways. Their lengths vary from 9,0 to 15,8 cm, weights from 8,9 to 40,0 g, age 1+ and 2+ (Gritzenko, 1973, 1990, 2002). Masu salmon in the northeastern Sakhalin rivers are larger than in the southern water courses (Gritzenko, 1973, 1990, 2002; Krykhtin, 1962; Makeev et al., 1990).

Marine commercial species In the 1950s of the last century a constant fishing had been conducted in the bays Nyivo, Chaivo, and Piltun. Fishing expeditions operated in the Nabil Bay. Fishery camps were located along the bays’ shores. Fishing was conducted by beach seines and fixed nets (summer-autumn), under-ice fyke nets (winter). Herring, Pacific salmon, saffron cod, and starry flounder were the main commercial objects (Table 7.9.2) (Report…, 1957). At present, the bay fishery has a seasonal character. Spawning aggregations of Pacific herring in the spring-summer period, and saffron cod and flathead sculpin in the winter period make up a base of the fishery. Pacific salmon (mainly pink and chum) are captured during their spawning migrations. Mainly, they are captured in the Nyisky Bay. In addition, chum salmon were captured in the bays Chaivo, Piltun, and Nabil in small numbers ( not more than several tons). Starry and banded flounders, redfins, smelts, Sakhalin char, eelpout (recently, Sakhalin taimen) being captured as a bycatch have a secondary importance in the fishery. Smelts are fished in May, during the spawning migration in the river mouths. Their maximum catch was 80 t in 1979 (Ivshina, 1992). A winter fishing in the northeastern Sakhalin bays is conducted by the fixed gear – fyke nets. A peculiarity of the winter fishing is the fact that several fish species are captured simultaneously: saffron cod, flathead sculpin, banded flounder, eelpout, Pacific smelt Osmerus mordax dentex; herring, starry flounder, and Steller’s sculpin occur in catches sporadically. A vital cycle of fish species being fished in winter is timed to the bays, where both their spawning and feeding take place. Periodically, saffron cod and flathead sculpin leave the bays and move to the open part of the sea, but at the depth not more than 50 m, as a rule. Temporary settlements of the aboriginal patrimonial groups of the island people are located on the bays’ shores in the northeastern part of Sakhalin. People live there, mainly, since spring through autumn (information was obtained in the Department of National Policy of Administration of Sakhalin Region). They are nivkhs by nationality. As a rule, the settlements

СахНИРО Отчет по договору Y-00571 235 are located on spits separating the bays from the open part of the sea. People’s activity is based on conducting the natural economy. Their main specialization is based on fishing and processing the fish inhabiting the bays in different year seasons. During the anadromous migration of Pacific salmon through the bays to the river mouths, each patrimonial group receives quota from the State for fishing. In addition, non-commercial fish species are captured in different periods. Major representatives of aboriginal people live in stm. Nogliki. Aboriginal fishing is the most developed in the basin of Nyisky Bay (Table 7.9.3).

Pacific herring Clupea pallasii. In the northeastern Sakhalin bays the spawning herring is represented by the local population and “migrants”. Local herring is characterized by the low rate of growth; all its vital cycle is timed to the bays and shelf of the northeastern Sakhalin coast. A group of “migrants” is represented by fish with the higher rate of growth, making extent migrations (Ambroz, 1931; Frolov, 1950, 1964, 1968б; Andreev, 1963а, 1963б; Gritzenko, Shilin, 1979; Rybnikova, 1999). A portion of “migrants” is supposed to be dependent on hydrologic and ice conditions on the shelf of northeastern Sakhalin, and population (populations) abundance, making up the migrants (Frolov, 1968а; Pushnikova, Ivshina, 1999). Characteristic of spawning grounds, spawning substrate, and other indices is known in detail only for the Nyisky Bay. However, periodic surveys conducted in other bays allow reporting that spawning conditions and their distribution are analogous in all the bays. The earlier spawning in the Nyisky Bay can be considered as one of the main differences; this is connected with the earlier bay’s release from the ice due to the warming affect of the Tym River. The spawning herring in the Nyisky Bay have lengths from 14,5 to 36,5 cm. At the beginning of the spawning run, as a rule, the larger fish prevail, by the end of the season smaller ones, which is common for herring and observed all over its area (Naumenko, 2001). Practically annually the expressed decline in length in fish aggregations took place during the observation period. The mean length of fish reduced 1-6 cm by the end of spawning (Pushnikova, Ivshina, 1998; Schukina et al., 2000; Ivshina, 2002). The mean individual absolute fecundity (IAF) of herring in the Nyisky Bay was 40,5 thousand eggs (Ivshina, 1997). Herring dynamics of the spawning run and biological indices in 2002 corresponded to the long-term ones. Herring aggregations in the spawning period in 2002 in the Nyisky Bay were formed by specimens of 12,5 to 36,5 cm long, averaged 25,1 cm. The mean body length of the mature fish (14,5 cm and more) varied in 1992-2002 from 23,5 cm (1992) to 27,1 cm (1997). The mean age of fish varied from 4,8 to 7,3 years old (Fig. 7.9.1).

8 28 см 7 27 , АС 6 26 возраст

. 5 25 Длина .

сред 4 24

3 23 сред 1992 1994 1996 1998 2000 2002 год

средний возраст средняя длина

Fig. 7.9.1. Dynamics of the mean indices of herring length and age from the northeastern Sakhalin coast

СахНИРО Отчет по договору Y-00571 236 In 2002, fish weights from catches varied from 15 to 396 g, averaged 207,0 g. During ten years the mean body weight varied from 160,7 (1992) to 224,8 g (1999). A spawning stock of local herring in 2002 was presented in catches by the age cohorts of 2-12 years old; among them, 32,6 % was constituted by three- and four-year-old fish. In 2002, the mean age of fish, compared to 2001, somewhat decreased and constituted 6,0, due to the increase in portion of the younger fish. As in 2001, the 1996 and 1998 generations occurred in catches. Their proportions in 2002 were 14,4 % and 20,0 %, respectively (Fig. 7.9.2).

25 2001 20 2002

15 % 10

5

0 2345678910и< возраст, лет

Fig. 7.9.2. Age composition of herring from the northeastern Sakhalin coast in 2001-2002

As a rule, a group of migrants is formed by specimens at the age of 3 to 6, with prevailing the 3-4-year-old fish. The mean age of migrants in 2001 was 5,3 years old, and in 2002 it declined to 3,8. In 2002, only three- and four-year-old fish were observed among migrants. A ratio between local herring and migrants from catches varied annually. A proportion of migrants during the last five years (1998-2002) varied in catches from 7,3 % (1999) to 40,0 % (2000), averaged 15,1 %. A proportion of local herring during 1997-1999 increased, and in 2000 declined to 60,0 %. In 2001-2002, it again increased to 91,9 – 90,1 %. The long-term level constituted 84,9 %. The data on herring in the feeding period (July-October) were obtained during the bottom trawl surveys at R/V “Dmitry Peskov”. By the results of these surveys, it was revealed that herring was distributed, mainly, within the shelf zone between 51-53° N above the depths of 20- 150 m. A major part, mainly juveniles, was distributed at the depths less than 20 m (Frolov, 1968а; Shepeleva, 1999). However, by the results of such surveys, we can report only the distribution of herring; it is difficult to give quantitative estimates, since a bottom trawl is not adapted to the count of mobile pelagic fish, such as herring. By the data of bottom trawl catches, fish lengths in 2002 varied from 7,0 to 26,0 cm. Fish 16,0-23,0 cm long (94,3%) significantly prevailed by numbers (Fig. 7.9.3). Adult and maturing fish occurred, mainly, at depths more than 100 m. Fingerlings with body lengths of 7-9 cm occurred sporadically in October at the depth of about 20 m (Smirnov, 2002).

СахНИРО Отчет по договору Y-00571 237

20 18 16 14 12

% 10 8 6 4 2 0 7 8 9 1011121314151617181920212223242526 Длина АС, см

Fig. 7.9.3. Distribution of herring by body lengths along the northeastern Sakhalin during September 24 - October 18, 2002 (n = 352)

Herring has been captured for a rather long period in the study region. However, at the beginning of XX century this species was not of commercial importance. Chum and pink salmon made up the main capture. The enough complete statistics of herring capture exists only since 1931. Since this period the greatest catches had been recorded in 1936-1944 (1,41 thousand t, on average) and in 1954-1963 (1,90 thousand t, on average), when herring was the main object for fishing in the bays. The maximum catch for the all fishery period was 3295 t in 1961. Since 1967, herring catches declined sharply. Such a situation, perhaps, was a consequence of decrease in abundant broods, and excessive capture (Frolov, 1968а, 1969). The minimum catches were recorded in the 1970-1980s due to the low abundance and, in this connection, the absence of interest of the fishery companies. The mean annual catch of the 1968-1986 period was 126,8 t. The mean annual catch of herring for the last ten years (1992-2002) was 243,7 t; for the last five years (1998 – 2002) - 106. 1 t. Since 1995, fishing has been realized only in the Nyisky Bay. In 1994-1997, a decrease in the annual capture was observed; this is connected with the economic reasons, poor organization of fishery, and, in individual years, complex weather conditions (late flood on the Tym River, stormy weather) (Fig. 7.9.4).

3.5

3.0 2.5 т . 2.0 тыс

, 1.5

1.0 вылов 0.5

0.0 1931 1935 1939 1943 1947 1951 1955 1959 1963 1967 1971 1975 1979 1983 1987 1991 1995 год

Fig. 7.9.4. Herring catches in the bays of northeastern Sakhalin

Due to their natural small numbers, despite the rather great catches, herring of the northeastern Sakhalin always had the lowest stock and catch compared to the Sakhalin-Hokkaido

СахНИРО Отчет по договору Y-00571 238 and De-Kastry populations used by fishery. In general, a state of herring stock can be characterized as stable. Under the good fishery organization, a capture can constitute not less than 200 t (Schukina et al., 2000; Ivshina, 2000). In the period of high catches (1940-1960s) the fishery continued from May through October-November: spawning herring were captured in June-July, feeding herring since mid- June. A strength of herring entrances into the bays during the feeding period depended on the total abundance of their stock. Entrances of feeding herring had the irregular character being connected with the hydrological conditions in the sea. A relationship between the herring capture in the spawning period and strength of the feeding herring entrances into the bays was observed. When spawning herring was abundant from catches, in contrast, it was non-abundant in the feeding period (Frolov, 1968а, 1969). During the last ten years, herring has been observed annually in the bays in the feeding period (August-October), but we can’t speak about its commercial use at present, due to its low abundance (Pushnikova, Ivshina, 1998; Ivshina, 2001). Beach seines were used in fishery to the end of the 1960s. At present, fixed nets are used; places of their settling remained the same. Herring fishing had been realized in the 1930-1960s practically in all small and large bays (Urkt, Kolendo, Piltun, Chaivo, Nabil, Nyisky, Lunsky, and others). The bays Piltun, Chaivo, and Nyisky were the main commercial water bodies. In individual years the capture in the bays Piltun and Chaivo exceeded that in the Nyisky Bay, mainly, due to the feeding herring in August-October. In the spawning period, that is, in June, the herring fishing mainly occurred in the Nyisky Bay. A total capture of spawning herring did not exceed 1 thousand tons (Frolov, 1954, 1965). Since 1987 through 1994, herring had been caught in the bays Nyisky, Piltun, Chaivo, Nabil, and Lunsky. The proportion of catches from all the bays, except for the Nyisky Bay, was from 1,8 % (1994) to 9,3 % (1992) of the total capture (Fig. 7.9.5).

1400 1200 1000 т , 800 600 вылов 400 200 0 1946 1947 1948 1951 1952 1953 1954 1960 1961 1962 1968 1969 1987 1988 1989 1990 1991 1992 1993 1994 1995 год

Пильтун Чайво Ныйский Набиль Луньский

Fig. 7.9.5. Annual catch of herring along the northeastern Sakhalin by the bays

Since 1995, the bays Piltun, Chaivo, and Nabil have lost their commercial importance as for the herring fishery due to absent of interest of the fishery enterprises.

Saffron cod Eleginus gracilis. Saffron cod is related to traditional objects of the coastal winter fishery. This species, inhabiting northeastern Sakhalin coastal waters, plays an important part in the bottom biocenosis of the bays of lagoon type and adjoining waters of the Okhotks Sea. Its abundance is great enough, and among other objects this species occupies one of the leading places.

СахНИРО Отчет по договору Y-00571 239 Saffron cod forms spawning aggregations at the near-mouth sites of the straits joining the large lagoons Piltun, Chaivo, Nyivo, and Nabil with the Okhotsk Sea. Its spawning grounds are located at depths of 2-8 m. The greatest aggregations occur in the Piltun Bay, which proportion constitutes to 70 % of the total saffron cod caught in this region (Fig. 7.9.6).

90.0 80.0 70.0 60.0 улова

50.0 40.0 общего

от 30.0 % 20.0 10.0 0.0 1987 1988 1989 1990 1991 1992 Год промысла

Набиль Ныйво Чайво Пильтун Луньский

Fig. 7.9.6. Catches of saffron cod by the bays of northeastern Sakhalin since 1987 through 1992 (in % of the total catch)

There, fish spawning is stretched and occurs in January-February. Water temperature on spawning grounds vary from –1,2 to –1,9 °С. In the northeastern Sakhalin bays the maximum body length of saffron cod is 54,0 cm, that is the maximum value for Sakhalin-Kuril Region (Safronov, 1986). Specimens 18,0-26,0 cm long are the most frequent in commercial catches. The mean body length of saffron cod in the bays varied by years. For example, until 1994, an insignificant change in the mean length (from 21,5 cm in 1994 to 24,5 cm in 1988) was observed in the Piltun Bay; in 1996-97, the number of large fish increased greatly, and the mean length of saffron cod reached 27,4-28,6 cm. Another picture was observed in the Nabil Bay, where the maximum length of saffron cod was recorded in 1994 (30,6 cm), and then a decline in the mean length up to 24,8 cm (1997) took place. When characterizing the whole region, one can report that similar trends for the change in the mean length are observed in the bays Piltun, Chaivo (northern bays), Nyivo, and Nabil (southern bays). First maturing males and females are recorded at age 2 under the length 17,0-20,0 cm, when they enter the fishery. As a rule, at age 5-6 a portion of these generations in catches decreases significantly. The older specimens occur in catches, but their percentage is insignificant. The largest specimens of both sexes (more than 39,0 cm) are at age 10 (Safronov, 1986). A rate of recruitment of the spawning population depends on the rate of growth of the first spawning fish. Majority of saffron cod females from the northeastern Sakhalin (80,0-92,0 %) mature under the length of 17,0 cm, and 100 % of fish mature under the length of 20,0 cm (Safronov, 1986). As a rule, fish spawning takes place in January-February in the coastal zone with the sandy-pebble ground and strong tidal currents, at depths of 2-10 m. A great freshening (to 25,0 %) and water temperature higher than –1,2 °С are unfavorable for spawning and eggs’ development (Kozlov, 1956). Saffron cod spawning is annual, and each specimen of the considered population spawns, on average, 5-6 times during its life. The eggs of saffron cod are demersal, which provide a small distribution and development in the favorable conditions. Its spawning is non-recurrent. The coefficient of the female maturity constitutes 25,0-31,0 % by the beginning of spawning.

СахНИРО Отчет по договору Y-00571 240 Studies on the abundance dynamics of the saffron cod population have been conducted on the base of long-term materials on the age structure of the Piltun Bay saffron cod (due to the fact that major saffron cod are captured in this bay, and the collected material is representative) and data on catches. A stock value of any biological objects is not constant. As it is known, a commercial fish population consists of some generations of different numbers. In the considered period (1976- 2001), numbers of broods (numbers of generations at age 2 – the year of entering into the fishery and full representation in the catches are analyzed) varied from 1,4 to 16 billion ind., that is, the greater brood by numbers exceeds the lesser one more than 11 times. In other habitat regions of saffron cod, the multiplicity of fluctuations of the abundant broods constitutes 8 in the Terpeniya Bay, and 10 in the Sakhalin Bay. Numbers of the abundant broods of the Yamskaya population of the Okhotsk Sea exceeds the non-abundant broods 6-7 times (Semenenko, 1973); along the northeastern coast of Kamchatka, the abundance of saffron cod broods changed 5 times, and along the western coast - 30 times (Tolstyak, 1985). Analyzing the abundance of saffron cod generations from the northeastern Sakhalin, two periods can be distinguished. The first is the 1976-1984, when the mean abundance of generations constituted 11 billion ind. (under variations 8,0 – 15,9 billion ind.), and the second - since 1985 through the present time, when the abundance of generation declined significantly. The 1987 brood was the greatest by numbers, it reached 7,4 billion ind.; minimal - 1,4 billion ind. A value of commercial stock changed respectively. The maximum biomass of the commercial part of saffron cod population was observed in 1985 – 1,8 thousand t; minimal in 1993, 1994, 2000, 2001 – 0,47-0,41 thousand t. The coefficient of commercial mortality varied from 0,5 to 0,8 since 1978 through 1985, that corresponded to 39,0 and 55,0% of losses. Since 1986, when, evidently, the capture exceeded the biological abilities of population, saffron cod catches increased to 67% (on average) under the maximum estimate of 83,0 % in 1993, which, undoubtedly, negatively affected the stock state. A history of the saffron cod commercial fishery (by the data of commercial statistics) begins since 1938. As a rule, the mean duration of fishery constitutes 85-110 days. Saffron cod approach to the shore after settling the negative temperature, which usually coincides with settling the ice-foot in late November – December. Fishing begins in December and finishes in mid- late-March. As a rule, the greatest catches occur in the second decade of January – third decade of February. A character of the ice-foot is important for a successful fishing. If the ice is even, without the underwater and above-water hummocks, the gear settling is easier, and favorable conditions are being formed for fish approaches to the shore. In the northeastern Sakhalin bays the powerful underwater hummocks are formed in the region of fairway joining the bays with the sea in individual years; this is unfavorable for a successful fishing (Kozlov, 1956). During the whole period of observations, a size of catches varied from 31,2 (2002) to 960 tons (1984) (Fig. 7.9.7). No great changes occurred in the saffron cod fishery till the 1970s. The mean catch during that period was 250 t. Then the commercial press increased gradually, and by the end of 1980s the mean catch was 400 t. Since the 1990s, a size of catches again began to decline, and the mean estimate in that period did not exceed 180 t. In the new century the size of catches declined more (Table 7.9.5).

СахНИРО Отчет по договору Y-00571 241

1 0.9 0.8 0.7 0.6 . т . 0.5

Тыс 0.4 0.3 0.2 0.1 0 1938 1943 1948 1953 1958 1963 1968 1973 1978 1983 1988 1993 1998 Год, промысла

Fig. 7.9.7 Catches of saffron cod in the northeastern Sakhalin bays since 1938 through 2002

Table 7.9.5 Dynamics of the mean catch of saffron cod since 1938 through 2002, in tons 1938- 1951- 1961- 1971- 1981- 1991- 2001- Years 1950 1960 1970 1980 1990 2000 2002 Catch 246 283 236 338 394 179 31

A number of gear used during fishing changed too. In the 1940-60s the number of fyke nets was about 150 (Lestyev, Grischenko, Kozlov, 1956), in the 1980s it varied from 182 to 248; at present it does not exceed 120-130 units. The maximum number of saffron cod was captured in the Piltun Bay (60,0 – 70,0% of the total catches), there the maximum catch per a fyke net was recorded. If by the data of studies the mean catches per a fyke net did not exceed 100-300 kg in the bays Chaivo and Nyivo in the 1990s, then in the Piltun Bay they reached 500 kg and higher. The expedition saffron cod fishery was organized in the Nabil Bay.

Flathead sculpin Megalocottus platycephalus Flathead sculpin is the dominant species from the fyke net catches in winter period. This species occurs only on sandy grounds at depths to 30 m. Its biology is weakly studied. But, evidently, it does not move far, and the short-extent migrations from the sea into the bays and back are common for flathead sculpin. This is proved by both the analysis of the fixed and beach seine catches in lagoons during the summer period, where sculpin is presented in rather great numbers, and the catches of scientific-research ships on the shelf of northeastern Sakhalin. In the sea the flathead sculpin occurs at 10-15 m depth, and individual specimens reach 50 m in the summer period. Flathead sculpin is characterized by the second type of size-sex relationships (Volodin, 1993, 1999), for which a sex dimorphism (when females are larger than males) is common. By the data of SakhNIRO (1990-1993), the maximum length of flathead sculpin reaches 48,0 cm in lagoons of the northeastern Sakhalin, and weight 1400 g. Fish with the maximum sizes are always females. The length of males does not exceed 36,5 cm, and weight 610 g. The males 20,0-28,0 cm long and 100-150 g weigh make up the base of catches, females, respectively 25,0- 37,0 cm and 200-450 g, which summarized portion constitutes 70,0-80,0% of the total fish numbers. The maximum age for females of the flathead sculpin is 16 years old, males – 13. As a rule, the age composition is presented by 11-12 age groups. Flathead sculpin can be related to the hard-growing fish, which is explained by the habitat conditions of this species (a greater part of the year under low temperatures). The flathead sculpin maturation was recorded at age 2, under

СахНИРО Отчет по договору Y-00571 242 the length of 15,0-17,0 cm for males; the mass maturation occurs at the age of 3-4, under the length of 17,0-23,0 cm. Females first mature at the age of 3-4, under the length of 23,0-28,0 cm; and in mass at the age of 5, under the length of 29,0-31,0 cm. In late December – early January, the flathead catches per one trap lift in the 1990s varied from 1,0 to 3,0 tons, in late January 0,5-1,0 t, and in February did not exceed 0,5 t. The flathead sculpin spawning occurs in December-February; its peak occurs in late December – early January, and just in this period its catches are maximal. Spawning takes place under the negative temperatures (from–0,4 to –1,7 °С), only on sandy grounds, and at depths of 2-8 m. The eggs of flathead sculpin are rather adhesive and laid as lumps. Spawning is non-recurrent. A fishing of flathead sculpin is conducted, as reported above, during the period of forming the dense spawning aggregations. It is practically impossible to determine the flathead sculpin stock, since the data of commercial statistics are not certain. By the data of SakhNIRO (Volodin, 1993), other fish species constantly occur in the flathead sculpin catches; banded flounder makes up the greatest part of the bycatch, which proportion may reach 70,0 %. The “sculpin” catches in the bays by the data of commercial statistics (which is not certain) are presented in Fig. 7.9.8, 7.9.9. The maximum catch reached 5,5 thousand t. On the whole, it can be stated that a stable decline in sculpin catches takes place in recent years.

7000 6000 5000 . т . 4000 тыс 3000 2000 1000 0 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 Годы

Fig. 7.9.8. Catches of flathead sculpin in the northeastern Sakhalin bays

50.0 45.0 40.0 35.0 улова 30.0 25.0 общего

20.0 от 15.0 % 10.0 5.0 0.0 1987 1988 1989 1990 1991 1992 Годы наблюдений

Набиль Ныйво Чайво Пильтун Луньский

Fig. 7.9.9. Catches of sculpin by the bays of northeastern Sakhalin since 1987 through 1992 (in % of the total catch)

СахНИРО Отчет по договору Y-00571 243

Starry flounder Platichthis stellatus There are not many regions along the shore of Sakhalin, where the starry flounder abundance would not prevailed above the other species from the family Pleuronectidae. The most abundant population of this species inhabit the region of northeastern Sakhalin. The relative numbers of the other flounder species, compared to starry flounder, are insignificant (Bukin et al., 1999; Smirnov et al., 2000). Its biomass reaches great values (Pometeev, 2001а). The occurrence of the developed net of marine lagoons, which are favorable for juvenile flounders may be one of the reasons of the starry flounder great abundance. Mature fish form the greatest commercial aggregations along the northeastern Sakhalin shores in the open part of the sea, not far from the bays, at small depths (less than 10-40 m) (Bukin et al., 1999; Smirnov et al., 2000; Pometeev, 2001а). At the same time the individual specimens were recorded up to the depth of 137 m (Pometeev, 2001б). In the open part of the sea the base of catches was constituted by specimens 28,0 – 40,0 cm long. The maximum size of starry flounder in this region was 61,0 cm, and weight 3300 g (Smirnov et al., 2000; Pometeev, 2001б). The large sizes of fish are explained by the complete absence of specialized fishery. It has been recorded that in the open part of the sea, males dominate by numbers in the size groups less than 34,0 cm; among large fish – females (Pometeev, 2001б). The males, maturing earlier, leave lagoons. Evidently, this is the cause why females dominate by numbers in the younger age groups. Based on the obtained data, one can resume that starry flounder occupy a vast habitat area of the coastal sea part along the northeastern Sakhalin shore. In the habitat places of this species, sea sites significantly differ one from another by their hydrologic characteristics. This proves a great ecological plasticity of starry flounder. In addition, it is supposed to change the preferable habitat areas as far as being developed. In the first approximation, a scheme of habitat area for starry flounder during the ontogenesis process can be presented as follows: a) along Sakhalin shore the spawning occurs in the open part of the sea, at depths, mainly, to 60 m (Pertseva-Ostroumova, 1961); b) eggs and larvae develop in the sea, in the water column (Pertseva-Ostroumova, 1961); c) metamorphose and fry’s settling on the ground are realized in the sea; d) fry migrate to the freshened areas of the sea (including the bays) and low river parts; e) fish from the younger age groups (until the period of sex maturity) inhabit, mainly, the strongly freshened sea areas, particularly in the bays and low parts of large rivers; f) mature fish occur, mainly, in the open part of the sea.

Banded flounder Pleuronectes pinnifaciatus Banded flounder has the leading role among other flounders in the winter fishery. This species is a coastal form, inhabitant of the upper layers of the sublittoral zone, not lowering deeper than 30 m during the year (Moiseev, 1953). Being widely euryhaline, banded flounder prefers the coastal sites with silty-sand grounds during the life cycle. The major part of the year it spends under the negative temperatures in the strongly freshened waters, and enters the rivers moving up against the current, upper a zone of the head of salty waters. Biology of the banded flounder in seawaters adjoining to Sakhalin is weakly studied. This species is characterized by small sizes. Its maximum length is 40,0 cm. However, in mass this species is presented by small individuals. The mean length of the banded flounder in the Nabil Bay, for example, is 24,3 cm, and in the Nyivo Bay 20,8 cm. Different-sex specimens of this species differ by their lengths rather significantly. Males are smaller than females: in the Nabil Bay, for example, the mean length of males is 18,8 cm, females 25,9 cm. Biological indices of fish prove the fact that almost all the life cycle of this flounder in the northeastern Sakhalin occurs in the bays. By the episodic observations, the banded flounder spawning occurs in January – February. It should be noted that specimens begin to spawn under the body length of 11 cm

СахНИРО Отчет по договору Y-00571 244 (males) and more. In the winter conditions, practically all specimens (males and females) are mature. The eggs are large, not adhesive, demersal. Banded flounder occurs in the commercial fyke net catches practically in all the bays. Because this species is related to the comparatively small flounders, its major part has been landed by fishermen as “sculpin” during recent ten years. Other flounder species (longsnout flounder Limanda punctatissima, Alaska plaice Pleuronectes quadrituberculatus and others) occurred sporadically in the bays, as a rule, in the straits joining the bays with the open part of the sea.

Pacific eelpout Zoarces elongates This coastal species does not avoid the freshened sites of the bays. It enters the river mouths, occurs in the littoral zone and upper horizons of the sublittoral zone, as a rule, not lowering deeper than 20-30 m, prefers sandy grounds with Zostera thicket and algae. In the northeastern Sakhalin bays, Pacific eelpout occurs round the year, and even in the summer- autumn period has not been found during scientific researches in the open part of the sea. Usually, its length does not exceed 30,0-40,0 cm, although the maximum length may reach 50,0 cm. During the winter researches, Pacific eelpout was presented, mainly, by mature specimens with lengths from 31,0 to 46,0 cm. Their weights varied from 130 to 390 g. In the summer period the length of Pacific eelpout varies from 20,0 to 37,0 cm from the catches of fixed and beach seines. It reaches sex maturity at the second year of life. Specimens of the maximum age (9+) were found. Pacific eelpout is a viviparous fish, laying from 10 to 405 fry. By the moment of spawning, fry reach the length of 37-40 mm and immediately begin to feed actively. The pre- spawning females of Pacific eelpout occur in catches during the winter fishery in the bays of the northeastern coast. Thus, a total of 60 fish species from 26 families have been found in the bays of northeastern Sakhalin. The greatest species diversity of ichthyofauna was recorded in the bays Piltun, Chaivo, and Nyisky. A fishery has a seasonal character in the bays. At present, the chum and herring fishing in summer, as a rule, and saffron cod, “sculpin” in winter. Of anadromous fishes, Pacific salmon are of commercial importance. Coho salmon makes up a bycatch during the chum and pink fishing. These species are captured during their anadromous migration through the bays to the rivers. A specialized chum salmon fishery has been closed since 1993. At present, the total estimate of chum capture consists of fish caught in the regime of the control catch, for own needs of the aboriginal people, and for using in fish culture. Chum salmon are caught by nets and trap net near the hatcheries. Herring spawning and feeding take place in the northeastern Sakhalin bays. A stock and catch of herring in the northeastern Sakhalin was always lower compared to the Sakhalin- Hokkaido and De-Kastry populations of this species, used by the fishery. A stock state of the lagoon herring in the recent time period is characterized as stable. Capture is realized in the regime of a control catch. During its spawning period, saffron cod forms aggregations at the near-mouth sites of the straits joining the bays with the open part of the sea. This species forms the greatest commercial aggregations in the Piltun Bay (to 70,0 % of the total catch). Since 1985 through the present time the decline in saffron cod numbers takes place in the bays. Flathead sculpin is a dominating species from the fyke net catches in the winter period. Its fishery is conducted in the period of forming the spawning aggregations. The total capture of “sculpin” consists of the flathead sculpin catches itself, banded flounder, Pacific eelpout and others. In recent years a decline in “sculpin” catches is observed. Banded flounder makes up the greater part during the fishery of saffron cod and “sculpin”; its percentage ratio in catches, for example during the “sculpin” fishing, may reach 70,0%.

СахНИРО Отчет по договору Y-00571 245 Starry flounder, which forms commercial aggregations on the shelf of northeastern Sakhalin, is the most perspective among the potentially commercial species. Biology of this species is closely connected with the bays being inhabited by the great part of its juveniles. The greatest damage may be done to fish population in the bays during a habitat period there of species, the most important for fishery (Pacific salmon, saffron cod, and others) and those being rare and needing in preservation (Sakhalin taimen Parahucho perryi). Table 7.9.6. shows some biological aspects of the main commercial fish species connected directly with their temporary or constant inhabiting in the bays. The time periods for fishery are given.

Table 7.9.6 Some biological aspects of the main commercial fish species and dates for their fishery in the bays Fish species Periods Anadromous Spawning Fry downstream Fishery migration migration Herring* During a year June-July Migration to a Since 1995 a sea in June- fishery is August practically absent Pink salmon July-August July-September May-June (early July-August July) Chum salmon July-September August-October May-June (July) August- (December) (December) September Coho salmon** September- October-November June-August August- November (December) September (December) Sakhalin taimen April-May May-June Spring-summer - Saffron cod During a year January-early No data Late December February – early February Flathead Constantly No data Constantly Late December sculpin** – early February Banded flounder Constantly Admittedly, late Constantly Late December spring – early February Note. * - a main commercial object in the past; ** - caught as a “bycatch” when fishing other fish species.

СахНИРО Отчет по договору Y-00571 246 REFERENCES

1. Ambroz A.I. 1931. East-Sakhalin herring of the Nyisk-Nyivo region // Soc.reconstruction of rybnoye khozyaistvo of Far East. No. 5-6. P.129-135. 2. Andreev V.L. 1963a. Results of marking herring in the Nyivo Bay (northeastern Sakhalin) in 1963 // Izv. TINRO, V. 65. P. 257-258. 3. Andreev V.L. 1963b. Efficiency of herring spawning in Sakhalin waters and Aniva Bay in 1963. SakhNIRO archive, No. 984.- stm. Antonovo. 32 p. 4. Biochemistry of the ocean. 1983. M.: Nauka. 368 p. 5. Bobrik K.P., Brovko P.F. 1987. River run-off and sedimentation in lagoons of the northern Sakhalin //Materials of Scientific Conference on the problems of river hydrology of BAM and Far East zones. L.; Hydrometeoizdat. P. 439-444. 6. Brovko P.F. 1990. Development of coastal lagoons. Vladivostok: DVGU. 148 p. 7. Brovko P.F., Kafanov A.I. 1985. Lithologo-geomorphological conditions of development and littoral types of the Nabil Bay (eastern Sakhalin) //Benthos and conditions of its existence in Sakhalin shelf zones. Vladivostok: DVNC AS USSR. P. 20-26. 8. Bukin S.D. et al. 1999. Report on conducting a trawl-acoustic survey at RV “Dmitry Peskov” in the region of northeastern Sakhalin in September-November 1999. Yuzhno- Sakhalinsk, SakhNIRO archive, No. 8389. 96 p. 9. Vedensky A.P. 1950. Some data on herring of the eastern Sakhalin //Izv. TINRO. V. 32 P. 55-63. 10. Veideman E.L., Kovekovdova L.T. 1991. Heavy metals in the seagrasses of zosteraceae in Peter the Great Bay // Oceanology V. 31, No. 5. p. 749 – 753. 11. Velikanov A.Ya., Mikheev A.A. et al. 1997. Ecological mapping of the northeastern Sakhalin shelf. State of ecosystem and oil pollution of Nyisky Bay by the results of monitoring of 1995-1996. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, 168 p. 12. Volodin A.V. 1993. On some biological features of flathead sculpin from lagoons of the northeastern Sakhalin coast. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 6504. 26 p. 13. Volodin A.V. 1999. A size-age composition and growth of flathead sculpin Megalocottus platycephalus (Pallas) in lagoons of the northeastern Sakhalin coast // Fisheries researches in Sakhalin-Kuril region and adjoining areas. V. 2, P. 143-146. 14. Vladimirov A.S. 1961. Morphology and evolution of lagoon shores of the Sakhalin Island //Dynamics and morphology of sea shores. M.: AS USSR. P. 145-171. 15. Volova G.N., Kozmenko V.B. 1984. Benthos of the Chaivo Lagoon (Sakhalin Island) //Fauna and ecology of marine organisms. Vladivostok: DVGU. P. 125-136. (Deposit in VINITY, № 3651-84). 16. Voronov G.A., Basarukin A.M., Neverova T.I. 1990. Modern state and changes in fauna of mammals, birds, and amphibious from the bays Baikal, Chaivo, Piltun, Astokh, and adjoining land territories due to the development of oil-gas fields of the northern Sakhalin and its shelf. Yuzhno-Sakhalinsk: AS USSR DVO IMG and G. 55 p. 17. GOST 17.1.4.02-90. Water. Methods of spectrophotometric determination of chlorophyll “a”. 18. GOST 12536-79. Grounds. Methods of laboratory determination of particle-size and microaggregate composition. 1980. М.: State Committee on construction. 24 p. 19. GOST 23740-79. Grounds. Methods of laboratory determination of organic matter. – M.: Gosstroy USSR, 1979. 20. GOST 17.1.5.05-85. Nature preservation. Hydrosphere. General demands for sampling surface and sea waters, ice and atmospheric precipitation. 21. Gritsenko O.F. 1973. Biology of masu and coho salmon of the northern Sakhalin. Scientific report, VNIRO. Theme 10. 40 p.

СахНИРО Отчет по договору Y-00571 247 22. Gritsenko O.F. 1969. Materials on biology of Sakhalin char Salvelinus leucomaenis (Pallas) from Sakhalin rivers //Proceedings of young scientists, VNIRO. No. 1. P. 113- 124. 23. Gritsenko O.F. 2002. Anadromous fishes of Sakhalin Island. Systematics, ecology, fishery. M.: VNIRO, 247 p. 24. Gritsenko O.F., Kovtun A.A., Kostkin V.K. 1987. Ecology of chum and pink salmon reproduction. M.: Agropromizdat. 166 p. 25. Gritsenko O.F., Kostyunin G.M. 1979. Ussuri whitefish Coregonus ussuriensis Berg and kaluga Huso dauricus (Georgi) in Sakhalin waters //Vopr.Ichthyol. V. 19, No. 6. P. 1125- 1127. 26. Gritsenko O.F., Churikov A.A., Rodionova S.S. 1984. The breeding ecology of the Asiatic smelt Osmerus mordax dentex Steindachner (Osmeridae) in Sakhalin rivers //Vopr.Ichthyol., V.24, No. 3. p. 404-416. 27. Gritsenko O.F., Shilin N.I. 1979. Ecology of spawning of the Nyisky Bay spawning (Sakhalin) //Biologia morya. No. 1. P. 58-65 28. Grishin A.F., Belobrzheskiy V.A., Zakharov A.V., Okunev L.E. 1989. Characteristic of ichthyofauna and fisheries characteristic of rivers and bays of the northeastern Sakhalin coast. Yuzhno-Sakhalinsk, SakhNIRO archive. 74 p. . 29. Zhulkov A.I. 1978. Biological peculiarities of coho salmon of the Sakhalin Island // Biology of salmon. Abstracts of International four-side Conference. Vladivostok.P. 40- 42. 30. Zverkova L.M., Velikanov A.Ya., Mikheev A.A. et al. 1997. Ecological mapping of the northeastern Sakhalin shelf. State of ecosystem and oil pollution of Nyisky Bay by the results of monitoring of 1995-1996. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, 164 p. 31. Zemnukhov V.V., Sobolevskaya E.I., Panchenko V.V., Antonenko D.V. 2001. A list of fish species of the Piltun Bay (northeastern Sakhalin) //Vopr.Ichthyol. V. 41, No. 3. P. 420-421. 32. Ivshina E.R. 1995. A ratio between the local (lagoon) herring and “migrants” in the northeastern Sakhalin bays //Ecology of marine and freshwater ecosystems. Abstracts of the Conference of young scientists. Vladivostok: TINRO. P. 36-37. 33. Ivshina E.R. 1997. Fecundity of lake herring of the northeastern Sakhalin bays //Sakhalin youth and science. Materials of the 1st inter-institute Conference. Abstracts. Yuzhno- Sakhalinsk. P. 32-34. 34. Ivshina E.R. 2001. Herring fishery in bays of the northeastern Sakhalin coast //Coastal fishery – XXI century: Abstracts of International Scientific-Practical Conference. Yuzhno-Sakhalinsk, September 19-21, 2001, P. 51-52 35. Kafanov A.I., Lysenko V.N. 1988. Biology of sea grass Zostera marina //Biota and communities of the Far East seas: lagoons and bays of Kamchatka and Sakhalin. Vladivostok: DVO AS USSR. P. 93-113. 36. Kafanov A.I., Plekhov S.P. 2001. Bottom communities of the Semyachik Lagoon (Kronotskiy biosphere reserve, eastern Kamchatka //Biologia moray. V. 27, No. 2. P. 121-127. 37. Kovekovdova L.D., Simokon M.V., Luchsheva L.N., Tsygankova N.A. 1991. Data of the heavy metals determination in seawater, ground, and hydrobionts of the northeastern Sakhalin shelf. Report № 7.0.01. Vladivostok: TINRO. 38. Kovtun A.A. 1995. State of chum and coho salmon stocks in the northeastern Sakhalin bays. Scientific report “State of salmon stock in Sakhalin-Kuril Region and elaboration of recommendations on their rational use”. Yuzhno-Sakhalinsk, SakhNIRO archive, 48 p. 39. Kovtun A.A. 2003. Modern state of stocks and assessment of chum salmon abundance for 2002. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, 30 p.

СахНИРО Отчет по договору Y-00571 248 40. Kovtun A.A., Khudya V.N. 1989. Estimation of possible damage to fisheries during the development of the sea oil-gas field Piltun-Astokh for the period of test exploitation. Report on work order 9/89 of January 10, 1989. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 5684. 23 p. 41. Kozlov V.M. 1956. Saffron cod biology and fishery from the northern part of Tatar Strait and Sakhalin bays. Yuzhno-Sakhalinsk, SakhNIRO archive No. 2917. 54 p. 42. Kolganova T.N., Mogilnikova T.A. 1999. Phytoplankton of the Nyisky Bay in August- September 1996, 1997 //Materials of ХХХIII Scientific-Methodic Conference of YuSGPI teachers (April, 1998): Reports. Part II. Yuzhno-Sakhalinsk: SakhGY. P. 176. 43. Krasavtsev V.B. 1991. Ecological report on the northeastern Sakhalin shelf. Hydrochemical and hydrobiological studies. Yuzhno-Sakhalinsk, DMIGE. 177 p. 44. Red Data Book of Sakhalin Reguion. Animals. 2000. Yuzhno-Sakhalinsk: Sakhalin Publishers. 190 p. 45. Krykhtin M.L. 1962. Materials on the river life period of masu salmon // Izv.TINRO. V. 48. P. 84-132. 46. Labay V.S. et al. 1999. Ecological monitoring of the eastern Sakhalin shelf zone when developing the sea oil-gas fields. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive. 279 p. 47. Labay V.S., Latkovskaya E.M., Pecheneva N.V., Krasavtsev V.B. 2000. Peculiarities of the structural macrozoobenthos organization in the lagoon with the expressed gradient of abiotic factors //Fundamental problems of water and water resources on the border of the third millennium: Materials of International Scientific Conference. Tomsk. P. 539-544. 48. Labay V.S., Samatov A.D., Polupanov P.V., Latkovskaya E.M., Gavrina L.Yu., Mogilnikova T.A., Bragina I.Yu., Pecheneva N.V., Nikitin V.D., Polteva A.V., Radchenko D.R. A state of the Piltun Bay ecosystem in June-July 1999. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 8274. 263 p. 49. Latkovskaya E.M. 1999. Chemical-ecological assessment of the northeastern Sakhalin bays: chlororganic pesticides and heavy metals. Candidate’s dissertation. Yuzhno- Sakhalinsk: SakhNIRO. 50. Latkovskaya E.M., Mironichev S.N. 1996. Content of some metals in bottom sediments of the Okhotsk Sea near northeastern Sakhalin coast in places of prospective drilling at Kyrinskaya area // Fisheries researches in Sakhalin-Kuril region and adjoining areas. V. 1, P. 111 -114. 51. Latkovskaya E.M., Pecheneva N.V., Nikitin V.D., Polteva A.N., Motylkova I.B., Zavarzin D.S. 2002. Characteristics of the Lunsky Bay ecosystem in July 2000. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 8969. 166 p. 52. Latkovskaya E.M., Samatov A.D., Krasavtsev V.B., Pecheneva N.V. et al. 2001. Ecological characteristics of the Nyisky Bay ecosystem in July 1999. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 8652. 243 p. 53. Lestyev A.V., Grischenko G.I., Kozlov V.M. 1956. Saffron cod fishery in Sakhalin waters. Soviet Sakhalin. 75 p. 54. Makeev S.S., Belovolov V.F., Nikiforov S.N. 1990. Biology of masu salmon in the freshwater life period //Rybnoye khozaystvo. No. 10. P. 42-43. 55. Methodical recommendations on the preparation of samples of the environmental objects and fish production for atomic-absorption determination of toxic metals. 1987. Vladivostok, TINRO, 14 p. 56. Mogilnikova T.A., Motylkova I.V., Latkovskaya E.M. 2001. Summer phytoplankton of the Nyisky Bay under anthropogenic pollution // Coastal fishery – XXI century: Abstracts of International Scientific-Practical Conference. Yuzhno-Sakhalinsk, September 19-21, 2001, P. 192. 57. Moiseev P.A. 1953. Pacific cod and flounders of the Far East seas //Izv.TINRO. V. 40. 289 p.

СахНИРО Отчет по договору Y-00571 249 58. Naumenko N.I. 2001. Biology and fishery of sea herrings of the Far East. P- Kamchatskiy: Kamchat. Publishers. 330 p. 59. Nemirovskaya I.A. 1997. Hydrocarbons of water, suspended matters, and bottom sediments of the Okhotsk Sea (distribution, forms of migration, genesis) //Complex studies of the Okhotsk Sea ecosystem. M.: VNIRO. P. 172 – 178. 60. Report of the Sakhalingosrybvod expedition on survey of rivers and bays of the northeastern Sakhalin in 1956 /Koposov A.F., Nikanorov V.E., Eliseev V.M. et al./. 1957. Yuzhno-Sakhalinsk: Sakhalingosrybvod. SakhNIRO archive. 70 p. 61. List of the fishery standards: tolerance limited concentrations (TLC) and tentatively safety levels of deleterious matters (TSLD) for water and water objects having a fishery importance. 1999. M.: VNIRO, 303 p. 62. Pertseva-Ostroumova T.A. 1961. Spawning and development of the Far East flounders. M.: AS USSR. 185 p. 63. PND F 14.1:2.110-97. Quantitative chemical analysis of water. Methods of conducting measurements on the suspended matters and total content of admixtures in samples of natural and purified sewage waters by the gravimetric method. 64. PND F 14.1:2:4.128-98. Quantitative chemical analysis of water. Methods of conducting measurements on the mass concentration of petroleum products in samples of natural, potable, and sewage waters by the fluorimetric method on the fluid analyzer «Fluorate- 02». 65. Polupanov P.V. 1999. Peculiarities of hydrologic regime of the Nyisky Bay //XI All- Russian Conference on Fishery Oceanography: Abstracts. Kaliningrad, September 14-18, 1999. M.: VNIRO. P. 36. 66. Pometeev E.V. 2001b. Some biological peculiarities of starry flounder from the northeastern Sakhalin coast //Coastal fishery – XXI century. Yuzhno-Sakhalinsk: Sakhalin Publishers. P. 96-97. 67. Pometeev E.V. 2001a. Distribution and stock of the starry flounder from the northeastern Sakhalin coast //Coastal fishery – XXI century. Yuzhno-Sakhalinsk: Sakhalin Publishers. P. 95. 68. Pushnikova G.M., Ivshina E.R. 1998. On spawning herring of the northeastern Sakhalin bays //Rybnoye khozaystvo. No. 2. P. 38-41. 69. Ravvinsky F.Ya., Voronova L.D., Afanasiev M.I., Denisova A.V., Pushkar I.G. 1990. Background monitoring of the land ecosystems pollution with chlororganic compounds. L.: Hydrometeoizdat. 270 p. 70. RD 52.10.243-92. Manual on chemical analysis of sea waters. 1993. S-Pb.: Hydrometeoizdat, 47 p. 71. RD 15-258-94. Methodic instructions for measuring mass concentrations of alpha-HCCH in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on- Don: AzNIIRKH. 14 p. 72. RD 15-259-94. Methodic instructions for measuring mass concentrations of Lindane in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 73. RD 15-260-94. Methodic instructions for measuring mass concentrations of beta-HCCH in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on- Don: AzNIIRKH. 14 p. 74. RD 15-261-94. Methodic instructions for measuring mass concentrations of heptachlor in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 75. RD 15-262-94. Methodic instructions for measuring mass concentrations of o,p-DDE in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p.

СахНИРО Отчет по договору Y-00571 250 76. RD 15-263-94. Methodic instructions for measuring mass concentrations of p,p-DDE in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 77. RD 15-264-94. Methodic instructions for measuring mass concentrations of o,p-DDT in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 78. RD 15-265-94. Methodic instructions for measuring mass concentrations of p,p-DDD in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 79. RD 15-266-94. Methodic instructions for measuring mass concentrations of p,p-DDT in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 80. RD 15-267-94. Methodic instructions for measuring mass concentrations of o,p-DDD in bottom sediment samples by the method of gas chromatography. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 81. RD 15-268-94. Methodic instructions for measuring mass concentrations of copper in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 82. RD 15-269-94. Methodic instructions for measuring mass concentrations of zinc in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 83. RD 15-270-94. Methodic instructions for measuring mass concentrations of chromium in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 84. RD 15-273-94. Methodic instructions for measuring mass concentrations of lead in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 85. RD 15-274-94. Methodic instructions for measuring mass concentrations of nickel in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 86. RD 15-275-94. Methodic instructions for measuring mass concentrations of cobalt in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 87. RD 15-270-94. Methodic instructions for measuring mass concentrations of chromium in bottom sediments by the method of X-ray-fluorescent analysis. 1994. Rostov-on-Don: AzNIIRKH. 14 p. 88. RD 52-226-91. Methodic instructions for measuring mass concentrations of general mercury in bottom sediments by the method of the flameless atomic absorption. 1990. Rostov-on-Don: AzNIIRKH. 14 p. 89. RD 15-228-91. Methodic instructions for measuring mass concentrations of acid-soluble forms of chromium in bottom sediments by the method of the atomic absorption with the thermal-electric atomization. 1990. Rostov-on-Don: AzNIIRKH. 14 p. 90. RD 15-229-91. Methodic instructions for measuring mass concentrations of acid-soluble forms of cadmium in bottom sediments by the method of the atomic absorption with the thermal-electric atomization. 1990. Rostov-on-Don: AzNIIRKH. 14 p. 91. RD 15-231-91. Methodic instructions for measuring mass concentrations of acid-soluble forms of lead in bottom sediments by the method of the atomic absorption with the thermal-electric atomization. 1990. Rostov-on-Don: AzNIIRKH. 14 p. 92. RD 15-232-91. Methodic instructions for measuring mass concentrations of acid-soluble forms of arsenic in bottom sediments by the method of the atomic absorption with the thermal-electric atomization. 1991. Rostov-on-Don: AzNIIRKH. 14 p.

СахНИРО Отчет по договору Y-00571 251 93. RD 15-241-91. Methodic instructions for measuring mass concentrations of acid-soluble forms of copper in bottom sediments by the method of the atomic absorption with the thermal-electric atomization. 1992. Rostov-on-Don: AzNIIRKH. 14 p. 94. RD 52.24.382-95. Methodic recommendations. Methods of conducting the measure procedure for mass concentration of phosphates in the water by the photometric method. 95. RD 52.24.419-95. Methodic recommendations. Methods of conducting the measure procedure for mass concentration of dissolved oxygen in the water by the titrimetric method. 96. R 52.24.353-94. Sampling the surface inland waters and purified sewage waters. 97. RD 52.24.509-96. Methodic recommendations. An order of conducting the works on the control of quality of hydrochemical information. 98. RD 52.24.268-86. Methodic recommendations. System of control for the accuracy of measurement results of indices for the pollution of the controlled environment. 99. Rybnikova I.G. 1999. Population structure of Pacific herring Clupea pallasi (Valenciennes) of Japan and Okhotsk seas //Abstract of dissertation c.b.s. Vladivostok. 23 p. 100. Rutenberg E.P. 1962. Review of fishes from the family HEXAGRAMMIDAE //Greenlings and possibilities of their interoceanic transplantation. M.: AS USSR. V. LIX. 100 p. 101. Rukhlov F.N., Zhulkov A.I., Benkovskaya M.L. 1976. Biological characteristics of masu salmon of the southern Sakhalin. Yuzhno-Sakhalinsk, SakhNIRO archive. 57 p. 102. Savvaitova K.A. 1964. Sakhalin char Salvelinus leucomaenis (Pallas) form the lakes of southern Sakhalin //Lakes of southern Sakhalin and their ichthyofauna. M.: MGU. P. 154-167. 103. Samatov A.D. et al. 1997. Ecological state of lagoons and upper divisions of the northeastern Sakhalin shelf zone by the beginning of development of the sea oil-gas fields. Scientific report. Yuzhno-Sakhalinsk, SakhNIRO archive. 115 p. 104. Safronov S.N. 1986. Ecology of saffron cod (Eleginus gracilis Tilesius) in Sakhalin-Kuril Region. Abstract of dissertation, c.b.s. Vladivostok. 21 p. 105. Safronov S.N. 1986. Ecology of saffron cod from the shelf of Sakhalin and southern Kuril islands. Dissertation, c.b.s. Yuzhno-Sakhalinsk. 223 p. 106. Safronov S.N., Nikitin V.D., Nikiforov S.N. et al. 2003. Species composition of ichthyofauna and fish distribution in bays of the northeastern Sakhalin //Vopr.Ichthyol. (in press). 107. Safronov S.N., Nikiforov S.N. 1995. Species composition and distribution of ichthyofauna of fresh and brackish Sakhalin waters // In: Materials of XXX scientific- methodical conference of the YuSGPI teachers. Yuzhno-Sakhalinsk: YuSGPI, P. 112- 124. 108. Semenenko L.I. 1973. Some conditions of abundance dynamics and natural reproduction of the Yamskaya population of saffron cod //Vopr.Ichthyol. V.13, No. 1. P. 1046-1056. 109. Smirnov I.P. et al. 2002. Results of conducting the trawl survey near the eastern Sakhalin and along the proposed route of tankers in the Tatar Strait in August-October 2002. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 9207. 134 p. 110. Smirnov I.P. et al. 2000. Report on conducting a trawl-acoustic survey at RV “Dmitry Peskov” along the eastern Sakhalin in July-November 2000. Yuzhno- Sakhalinsk, SakhNIRO archive, No. 8601, 324 p. 111. A list of fishing sites attached to the fishery companies of Sakhalin Region by Sakhalinrybvod, by June 1, 1998. 112. Tabunkov V.D., Averintsev V.G., Sirenko B.I., Sheremetyevsky A.I. 1988. Composition and structure of bottom inhabitants of the lagoons Nabil and Piltun

СахНИРО Отчет по договору Y-00571 252 (northeastern Sakhalin) //Biota and communities of the Far East seas: lagoons and bays of Kamchatka and Sakhalin. Vladivostok. P. 7-30. 113. Taranets A.Ya. 1936. Freshwater fishes from the basin of northwestern Japan Sea //Proceedings of Zoological Institute. M.-L.: AS USSR. V. 4. P. 483-537. 114. Taranets A.Ya. 1937. Brief key for fishes of the Soviet Far East and adjoining waters //Izv.TINRO. V. 11. 200 p. 115. Taranets A.Ya. 1937a. Materials for the knowledge of ichthyofauna of the Soviet Far East //Izv.TINRO. V. 12. P. 5-44. 116. Tolstyak A.F. 1985. Main biological features and peculiarities of abundance dynamics of the East-Kamchatka saffron cod. Scientific report. P-Kamchatsky: KoTINRO. SakhNIRO archive No. 5540. 55 p. 117. Background monitoring of the inland ecosystem pollution with chlororganic compounds. 1990. L.: Hydrometeoizdat. 270 p. 118. Frolov A.I. 1954. Spawning herring of the eastern Sakhalin coast. Yuzhno- Sakhalinsk, SakhNIRO archive, No. 602. 36 p. 119. Frolov A.I. 1950. On local forms of Sakhalin herring //Izv.TINRO. V. 32. P. 65- 71. 120. Frolov A.I. 1964. Morphological characteristic of Sakhalin herring // Izv.TINRO. V. 55. P.39-53. 121. Frolov A.I. 1965. Herring of the eastern Sakhalin coast. Stm. Antonovo,Yuzhno- Sakhalinsk, SakhNIRO archive, No. 1480. 54 p. 122. Frolov A.I. 1968a. A stock state of local herrings in Sakhalin waters. Yuzhno- Sakhalinsk, SakhNIRO archive, No. 1805. 56 p. 123. Frolov A.I. 1968b. Distribution and habitat condition for lake herring in Sakhalin waters //Izv.TINRO. V. 65. P. 20-34. 124. Frolov A.I. 1969. A stock state of local herrings in the northern part of the Tatar Strait and near the eastern Sakhalin coast in 1969. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 1881. 46 p. 125. Churikov A.A. 1978. Ecological relationship between salmonids in the bays of northeastern Sakhalin. Abstract of Dissertation, c.b.s. M.: VNIRO. 24 p. 126. Churikov A.A., Karpenko V.I. 1987. New data on distribution of the smelt Hypomesus japonicus (Brevoort) in waters of the USSR //Vopr.Ichthyol. V. 27, No. 1, P. 157-159. 127. Sakhalin shelf. 1975. /A.V. Zhuravlev, M.Kh. Livshits, B.K. Ostistiy et al. M.: Nedra. 1991 p. 128. Shepeleva O.N. 1999. Structure of catches and biological peculiarities of fishes from the upper sublittoral zone of northeastern Sakhalin. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 8128. 46 p. 129. Shershnev A.P., Shpak V.M., Chupakhin et al. 1992. A stock state of salmon in Sakhalin-Kuril Region in 1991. Yuzhno-Sakhalinsk, SakhNIRO archive. 155 p. 130. Shulkin V.M. 1991. Heavy metals in modern bottom sediments of the Amur Bay (Japan Sea). 47 p. (Deposited in VINITY № 4017-В-91) 131. Schukina G.F. et al. 2000. Results of additional exploration of the coastal fishery raw materials in Sakhalin Region and recommendations on its rational use. Report on the work order АД-2/10 of 30.05.99. Yuzhno-Sakhalinsk, SakhNIRO archive, No. 9024. 309 p. 132. Ecology of marine hydrobionts. Marine ecosystems. 1992. Vladivostok: TINRO. P. 44-46. 133. Ecological studies of the northeastern Sakhalin bays. 2001. Scientific report. Yuzhno-Sakhalinsk: Ecological Company of Sakhalin. 515 p. 134. Haertel L., Osterberg Ch. Ecology of zooplankton, benthos and fishes in the Columbia River estuary // Ecology. - 1967. - Vol. 48, - N 3. - P. 459-472.

СахНИРО Отчет по договору Y-00571 253 135. Ivshina E.R., Review on resource condition of commercial herring populations in the waters of the Sakhalin Island /Scientific reports of Hokkaido Central Fisheries Experimental Station.-2000.-№ 62.- рр. 9-15. 136. Kafanov A.I.. Plekhov S.P. Semyachik Lagoon (Kronotsky Reserve. East Kamchatka) and its benthic vegetation// Ocean Research. - 1998. - Vol. 20. no. 3. - P. 261-274. 137. Lyngby J.E., Brix H. Monitoring of heavy metals contamination in the Limfjord, Denmark, using biological indicators and sediment// The Science of the total Environment, 1987. V. 64. P. 239-252. 138. Lyngby J.E., Brix H. Heavy metals in eelgrass (Zostera marina L.) during growth and decomposition// Hydrobiologia, 1989. 176/177. P. 189-196. 139. Short J. et all Standard Operatiiong Procedures for the Analysis of Petroleun Hydrocarbons in Seawater, Marine Sediments. Marine Faunal Tissue at the Auke Bay Lab.

СахНИРО Отчет по договору Y-00571 254 APPENDIXES

СахНИРО Отчет по договору Y-00571 255 Appendix 1.1. Composition and dates for the field surveys in September 2002 Date Action 15.09.02 Departure from Yuzhno-Sakhalinsk Overnight stay in stm. Abramovka. 16.09.02 Leaving for the region of Piltun Bay. Casual camping (because of puncturing a tyre of KamAZ). 17.09.02 Replacing a wheel. Removal to the Piltun Bay coast. Camping. Sampling (stations 1,2,3). 18.09.02 Sampling (stations 4 – 8, 11). The boat engine overheating caused by choking up the water drains with plants. Failure of one engine. 19.09.02 Sampling (stations 9, 10) 20.09.02 Leaving for the Chaivo Bay. Camping (opposite Soniga Island). Hireing the engine «Yamaha» (30 h-p) in stm. Val. 21.09.02 Sampling (stations 1, 2). 22.09.02 Sampling (stations 3 – 9). 23.09.02 Leaving for the Nyivo Bay. Camping near the mouth of Dagi River. 24.09.02 Sampling (stations 1 – 6). 25.09.02 Sampling (stations 7 – 12). 26.09.02 Leaving for the Nabil Bay. Taking a new engine «Yamaha» (30 h-p) in the camp of SEIC, running-in a new engine. Living in the house of the dispatching office of the port Kaigan. 27.09.02 Sampling (stations 1 – 4, 9). 28.09.02 Sampling (stations 5 – 8). 29.09.02 Leaving for the Lunsky Bay. Camping in the region of warm springs. 30.09.02 Sampling (stations 1 – 9). 01.10.02 Leaving for the Nabil River. Camping near the Nabil River. Packing all the samples for transportation to Yuzhno-Sakhalinsk. 02.10.02 Departure of KamAZ with samples accompanied by two persons. The rest members of the expedition are working on the next contract. Arrival of KamAZ to Yuzhno-Sakhalinsk.

During the work period the weather was relatively favorable without rains and storms. No staying idle was due to the bad weather or some other reasons. The engine failure took place because of burning-out the filler of a head of cylinder block. In this connection, in November 19, 2002 the two stations were carried out not far from the camp on the calm water using one motor- boat without a convoy. Replacing the filler was done in the port Kalian. The other equipment and instruments operated properly.

A list of equipment and instruments: 1. Rubber boat «Favorite – 420» - 2 pieces 2. Boat engine «Yamaha» 30 л.с. – 2 pieces 3. Diesel generator 2,8 KVt – 1 piece 4. Navigator GPS «Garmin» – 2 pieces 5. Short-wave transmitter «Icom» – 3 pieces

СахНИРО Отчет по договору Y-00571 256 6. Satellite telephone «Qualcom» of the «Globalstar» system – 1 piece 7. Portable computer «Compaq Contura» - 1 piece 8. Sounder YSI-63 – 2 pieces 9. Dredger of Fredinger – 2 pieces 10. Small Juday (plankton) net – 2 pieces 11. Bathometer (5 liters) – 1 piece 12. Bathometer (10 liters) – 1 piece 13. Extractor L-1 – 1 piece 14. Peristaltic pump – 1 piece

Safety measures and environmental protection: A responsible person for maintaining safety measures during the period of works was the head of the field group S.N. Nikiforov. Before the beginning of expedition works all the members of expedition were instructed about safety measures. A short instructional advice took place every day before the boat moving to stations. All the members of expedition had water proof dress, and those who drove out by the boat had life jackets. Two motor-boats with a double set of instruments were going to each station for sampling. Both boats had transmitters and navigators GPS. One transmitter was on shore. A two-way communication with the work manager A.D. Samatov was accomplished by the satellite telephone. Information exchange took place every day in 13:30-14:00 and 20:00-20:30. In the case of emergency a communication with the manager of works (mobile telephone) was provided for any time round o’clock. There were 4 medical first-aid sets «FEST». All the members of expedition could render the first medical assistance to some extent (Certificates on safety basis). One of the expedition members, senior engineer D.S. Zavarzin, attended additional training courses for rendering the first medical assistance in the Company AEA by the demand of SEIC directly before the beginning of the field works. The expedition works have been conducted according to the principle of minimization of the negative impact on environment. Camping took place on the sites being already used by the aboriginal people for a stand. A distance from the camp to the nearest water body was 100 m in every case. All the waste were collected into the polyethylene bags, then into the plastic container, and utilized in the dumps of settlements. Paper waste was burned. Gas cookers were used for cooking, and diesel generator was used for heating and illuminating the camp. There were no wood felling and GSM spills as well as the other cases of environmental pollution.

Methods of works: Sampling has been conducted from the motor-boats by the standard methods, which references and short description are given in the corresponding chapter of the report. Before going for sampling, coordinates of stations were introduced into GPS based on the map-scheme. On the spot, because of impossible or dangerous coming to the pointed station, sampling was conducted in the nearest point to the station, where one could come. Changes compared to the program of works: 1 – sampling at all stations was done by a dredger; 2 – because of the defective oxygen sensor of the sounder, dissolved oxygen was measured by the Vinkler’s method; 3 – because of stations being significantly remote from the shore, the shore vegetation, roads, and other things were not inspected; entrance to the shore was hindered (shoals, water plants)

СахНИРО Отчет по договору Y-00571 257

Appendix 2.2.1 Results of hydrochemical studies in the Piltun Bay in 2002

0 2 - - 3- № st. Depth, m T, С S, ‰ рН О , N-NO2 , N-NO3 , Р-РО4 , Si, Petroleu Suspended Chlorophyll а, mg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 m matters, mkg/dm3 products, mg/dm3 mg/dm3 1 0.7 16.9 2.8 8.73 10.30 <0.5 5.0 110.2 652.0 <0.005 9.30 1.60 2 0.9 16.2 8.8 8.65 10.20 <0.5 5.0 39.0 840.2 <0.005 28.60 5.41 3 0.7 14.8 3.8 7.55 9.87 1.0 <5.0 50.4 264.0 <0.005 6.14 1.98 4 0.7 16.1 11.8 9.04 10.20 <0.5 <5.0 30.6 512.4 <0.005 11.64 8.02 5 0.4 17.8 1.0 8.82 10.30 <0.5 <5.0 18.0 1359.0 <0.005 15.69 2.70 6 0.4 11.4 0.1 7.27 8.93 0.5 11.0 48.0 1205.0 <0.005 2.50 1.02 7 0.5 13.1 0.3 6.92 10.00 1.1 5.0 59.1 1953.7 <0,005 5.15 2.46 8 0.3 16.1 6.5 8.51 9.99 <0.5 <5.0 17.6 639.2 <0.005 19.53 3.83 9 0.9 14.6 13.5 7.98 9.22 0.6 <5.0 42.0 840.0 <0.005 39.27 5.90 10 0.9 14.5 13.0 8.22 9.55 0.6 <5.0 29.0 656.4 <0.005 15.75 6.54 11 0.9 11.7 11.7 8.13 9.09 0.5 <5.0 33.3 508.3 <0.005 8.17 2.83

СахНИРО Отчет по договору Y-00571 258

Appendix 2.6.1 An annotated list of microalgae of the northeastern lagoons in September 2002 Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky BACILLARIOPHYTA * Achnanthes delicatula (Ktz) Grun. * Achnanthes exigua Grun. * * Achnanthes Hauckiana Grun. * Achnanthes lanceolata (Breb.) Grun. * * * * * Achnanthes lanceolata f. capitata O. Mull. * * Achnanthes lanceolata var. minuta (Skv.) Sheshukov * * * Achnanthes lanceolata var. rostrata (Oestr.) Hust. * * * * Achnanthes minutissima Ktz. B * * * Achnanthes minutissima var. cryptocephala Grun. * * Achnanthes taeniata Grun. N * * * * Actinopttychus undulatus (Bail.) Ralfs. * Amphiprora alata Ktz. * * Amphiprora paludosa W. Sm. * Amphiprora sp. * * * Amphora coffeaeformis Ag. * * * * Amphora crassa Greg. * * * * Amphora ocellata Donk. * * Amphora ovalis Kutz. * * * * Amphora sp. * * * Asterionella glacialis Castr. TBA N * * * Asterionella gracillima (Hantzsc.) Heib. * * * * Asterionella kariana Grun. B-Ar N * * Bacillaria paradoxa Gmelin. * Bellerochea malleus (Bright.) Van Heurck T-B N * Caloneis bacillum Grun. * * * Caloneis silicula (Ehr.) Cl. * * * СахНИРО Отчет по договору Y-00571 259

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Caloneis sp. * Campilodiscus echeneis Ehr. * * Campilodiscus sp. * * * * Campilodiscus sp. 1 * Cerataulina pelagica (Cl.) Hendey C N * Ceratoneis arcus (Ehr.) Kutz. * Chaetoceros convolutus Castr. P * * Chaetoceros curvisetus Cl. T-B N * Chaetoceros decipiens Cl. C P * * Chaetoceros didymus Ehr. N * * Chaetoceros peruvianus Bright. T-An P * Chaetoceros radicans Schutt TBA N * Chaetoceros sp. * * Chaetoceros subtilis Ostf. * * Cocconeis pediculus Ehr. * * * * * Cocconeis placentula Ehr. * * * * * Cocconeis scutellum Ehr. * * * * * Cocconeis sp. * Coscinodiscus concinnus Wm. Smith B N * Coscinodiscus Jonesianus (Grev.) Ostf. N * Coscinodiscus lineatus Ehr. * * Coscinodiscus radiatus Ehr. * Cyclotella caspia Grun. B N * * * * * Cyclotella litoralis Lange, Syvertsen N * Cyclotella meneghiniana Kutz. N * Cyclotella sp. * * * * Cylindrotheca closterium (Ehr.) Reimanet Lewin N * * * * * Cymbella naviculiformis Auersw. * Cymbella sp. * * * * * СахНИРО Отчет по договору Y-00571 260

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Cymbella tumida (Breb.) V.H. * Cymbella ventricosa Kutz. * * * Cymbella ventricosa var. hankensis Skv. * Diatoma elongatum (Lyngb.) Ag. * * Diatoma vulgare Bory * * * * * Diploneis interrupta (Kutz.) Cl. * Diploneis oculata (Breb.) Cl. * * Diploneis parma Cl. * * * * * Diploneis Smithii (Breb.) Cl B * * Ditylum brightwellii (West) Grun. T-B N * * * Epithemia argus Ktz. * * * * Epithemia zebra var. porcellus (Ktz.) Gran. * Eunotia arcus Ehr. * Eunotia exigua (Breb.) Rabenh. C * * * Eunotia gracilis (Ehr.) Rabench. * Eunotia monodon Ehr. C * Eunotia praerupta Ehr. * Eunotia valida Hust. * * * Eunotia veneris (Ktz.) O. Mull. * Fragilaria brevistriata Gran. * Fragilaria constricta Ehr. * Fragilaria construens (Ehr.) Grun. * * * Fragilaria construens var. binodis (Ehr.) Grun. * Fragilaria pinnata Ehr. * * * Fragilaria sp. * * * * Fragilaria virescens Ralfs. * Fragillaria construens (Ehr.) Grun. * Frustulia vulgaris Thw. * * * Gomphonema acuminatum Ehr. * СахНИРО Отчет по договору Y-00571 261

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Gomphonema acuminatum var. coronata (Ehr.) W. Sm. * * Gomphonema angustatum (Ktz.) Rabh. * * * * * Gomphonema constrictum Ehr. * * Gomphonema longiceps Ehr. * Gomphonema olivaceum (Lyngb.) Ktz. * * * * * Gomphonema parvulum (Kutz.) Grun. * * * * * Grammatophora marina (Lyngb.) Kutz. C N * Gyrosigma acuminatum (Kutz.) Rabenh. * * * Gyrosigma fasciola Ehr. * * * * Gyrosigma macrum W. Sm. * Gyrosigma scalproides (Rabh.) Cl. * Gyrosigma Spenceri (W.Sm.) * Gyrosigma tenuissimum (W. Sm.) Cl. * * Hantzschia amphioxis (Ehr.) Grun. * * * * Hemiaulus hauckii Grun. B-T N * Leptocylindrus danicus Cl. C N * * Leptocylindrus danicus Cl. C N * Leptocylindrus mediterraneus (H. Perag.) Hasle C N * Licmophora abbreviata Ag. C * * * * * Licmophora ehrenbergii (Kutz.) Grun. C N * * Licmophora hyalina (Ktz.) Grun. * Licmophora sp. * * * * * Melosira Juergensii Ag. * Melosira distans (Ehr.) Kutz. * * * Melosira granulata (Ehr.) Ralfs C * * Melosira islandica O. Mull. * * * * Melosira moniliformis (O. F. Mull.) Ag. Ar-B N * * * Melosira nummuloides (Dillw.) Ag. * * * * * Melosira sulcata (Ehr.) * * * * * СахНИРО Отчет по договору Y-00571 262

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Melosira varians Ag. * * * * * Meridon circulare Ag. * * * Meridon circulare var. constricta (Ralfs.) V.H. C * * * * Navicula amphibola Cl. * Navicula brasiliensis Grun. * * * Navicula cancellata Donk. * * * * Navicula crucicula (W. Sm.) Donk. * Navicula cryptocephala Kutz. * * * * Navicula elegans W.Sm. * * Navicula elongata Poretzky. * Navicula gastrum Ehr. * * * Navicula gracilis Ehr. * * * * Navicula hungarica Grun. * * Navicula hungarica var. capitata Grun. * Navicula lacustris Greg. * Navicula lanceolata (Ag.) Kutz. * * * * * Navicula latissima Greg. * Navicula lyra Ehr. B-T * * Navicula menisculus Schum. * * * * * Navicula monilifera Cl. * Navicula mutica Kutz. * * * Navicula mutica var. binodis Kutz. * * Navicula peregrina (Ehr.) Kutz. * * * Navicula placentula (Ehr.) Grun. * Navicula pusilla var. lanceolata Gran. * * * Navicula pusilla W.Sm. * * Navicula pygmaea Kutz. * Navicula radiosa Kutz. * * * * * Navicula rhynchocephala Kutz. * * * * СахНИРО Отчет по договору Y-00571 263

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Navicula rostellata Ktz. * Navicula semen Ehr. * Navicula sp. * * * * * Navicula sp.1 * * Navicula transitans Cl. Ar-B * * * * Navicula transitans var. derasa (Grun.) Cl * * * Navicula transitans var. derasa f. delicatula Ar N * * Navicula tuscula Hust. * Navicula tuscula f.minor Hust. * Navicula viridula Kutz. * * * * Navicula viridula var. slesvicensis (Grun.) Cl. * Neidium dubium (Ehr.) Cl. * Nitzschia acicularis W. Sm. * * * * Nitzschia acuminata (W. Sm.) Grun. * Nitzschia angularis W.Sm. B-Ar* * * * Nitzschia denticula Grun. * Nitzschia longissima (Breb.) Ralrs. * * Nitzschia Lorensiana var. incurva Grun. B-T * * * Nitzschia Lorenziana Gran. * * * * * Nitzschia obtusa W. Sm. * * * * Nitzschia palea (Kutz.) W.Sm. * * * * * Nitzschia paleaceae Grun. * * * * Nitzschia reversa W.Sm. * * * * * Nitzschia romana Grun. * Nitzschia sigma (Kutz.) W.Sm. * * * * * Nitzschia sp. * * * * * Nitzschia sp. 1 * Nitzschia stagnorum Rabench. * Nitzschia sublinearis Hust. * * * СахНИРО Отчет по договору Y-00571 264

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Nitzschia subtilis (Ktz.) Grun. * Nitzschia tryblionella Grun. * * Nitzschia tryblionella var. debilis (Arn.) A. Maye * * * * Nitzschia tryblionella var. levidensis (W. Sm.) Gr * * * * * Nitzschia tryblionella var. victorae Grun. * Nitzschia vermicularis (Kutz.) Grun. * Odontella aurita Ag. TBA N * * * * * Odontella longicruris (Grev.) Hoban. T-B N * * Pinnularia brevicostata Cl. * Pinnularia dactylus Ehr. * Pinnularia quadratarea Oestr. * Pinnularia viridis (Nitzsch.) Ehr. * * * * * Pinnularia viridis var. leptogongyla (Ehr.? Gran) * Plagiogramma sp. * * * * Pleurosigma angulatum (Queck.) W.Sm. * * * * * Pleurosigma elongatum W. Sm. * * * * * Pleurosigma elongatum var. kariana Gran. * Pleurosigma formosum W.Sm. C * * Pleurosigma Glevei Grun. Ar * * Pleurosigma Normanii Ralfs. * Pleurosigma sp. * Pseudo-nitzscia pungens (Grun. ex Cleve) Hasle * * Rhabdonema adriaticum Ktz. * Rhabdonema arcuatum (Lyngb.) Ktz. * * * Rhizosolenia fragilissima Bergon C N * * Rhizosolenia setigera Bright. C N * * * * Rhizosolenia stolterfothii H. Perag. C N * Rhoicosphaenia curvata (Ktz.) Grun. B * * * * * Rhopalodia gibba (Ehr.) O. Mull. * * СахНИРО Отчет по договору Y-00571 265

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Rhopalodia gibberula (Ehr.) O. Mull. * Rhopalodia musculus ( Kutz.) O. Mull. * * * * * Rhopalodia sp. * * Sceletonema costatum (Grev.) Cl. T-B N * * * Scoliotropis latestriata (Breb.) Cl. * Stauroneis anceps Ehr. * * * Stauroneis baicalensis Scv. * Surirella angustata Ktz. S. * Surirella Capronii Breb. * * * Surirella linearis var. constricta (Ehr.) Gran. * * * Surirella linearis W.Sm. * * Surirella ovata Ktz. * * * * * Surirella sp. * Synedra actinastroides Lemm. * * * * Synedra Goulardii (Breb.) Grun. * Synedra hyperborea Grunow * Synedra parasitica (W. Sm.) Hust. * Synedra pulchella (Ralfs.) Ktz. * * * * * Synedra sp. * Synedra tabulata (Ag.) Kutz. * * * * * Synedra tabulata var. acuminata Grun. * Synedra ulna (Nitzsch.) Ehr. * * * * Tabellaria fenestrata (Lyngb.) Kutz. * * * * Tabellaria flocculosa (Roth.) Ktz. * * Tetracyclus rupestris (A.Br.) Grun. * * Thalassionema frauenfeldii Grun. T-B O * * Thalassionema nitzschioides Grun. C P * * * * * Thalassiosira anguste-lineata (A.S.) G. Fryx. et H Ar-B N * * Thalassiosira decipiens (Gran.) Jorg. B * СахНИРО Отчет по договору Y-00571 266

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Thalassiosira eccentrica (Ehr.) Cl. B-T N * * * * Thalassiosira nordenskioeldii Cl. B-Ar N * * * * Thalassiosira pacifica Gran et Angst B N * * * * * Thalassiosira punctigera (Castr.) Hasle B N * * * * Thalassiosira sp. * * * * * Thalassiosira sp.1 * * Thalassiosira sp.2 * Tropidoneis sp. * CHLOROPHYTA Ankistrodesmus arcuatus Korschik. * * * Ankistrodesmus convolutus Corda * * * * * Binuclearia lauterbornii (Schmidle) Pr.-Lavr. * * Carteria sp. * Chlamidomonas bullosa Butch. * Chlamydomonas sp. * Crucigenia fenestrata Schmidle * Crucigenia quadrata Morren * Dictyosphaerium pulchellum Wood. * Koliella sp. * Koliella spiculiformis (Vischer) Hind. * * * Lagerheimia quadriseta (Lemm.) G.M. Smith. * Lagerheimia sp. * Oocystis rupestris Kirchn. * Pterosperma sp. * * * Pyramimonas sp. * * * * Scenedesmus bijugatus (Turp.) Lagerh. * * Scenedesmus quadricauda (Turp.) Breb. * * * Spirogira sp. * Tetraselmis sp. * * * СахНИРО Отчет по договору Y-00571 267

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky CHRYSOPHYTA Chrysochromulina sp. * * * * Dinobrion sociale Ehr. * Dinobryon sp. * Distephanus speculum (Ehr.) Haeck. C * * * * Ebria tripartita (Schum.) Lemm. B N * * * CRYPTOPHYTA Chlamidomonas sp. * Chroomonas nana Butch. * Chroomonas sp. * * * * * Cryptomonas sp. * * * * * Cryptomonas sp. 1 * * Cryptomonas sp.2 * Isoselmis sp. * Plagioselmis prolonga Butch. B * * * * * Plagioselmis punctata Butch. * * * * * Plagioselmis sp. * * * * * CYANOPHYTA Anabaena Scheremetievi Elenk. * * Anabaena sp. * * Anabaena spiroides Kleb. * * * Coelosphaerium kuetzingianum Nag. * * * * Gomphosphaeria aponina Kutz. * * * Lyngbia sp. * Merismopedia punctata Meyen * Merismopedia sp. * Merismopedia tenuissima Lemm. * * * * Microcystis aeruginosa Kutz. * Microsystis pulverea Elenk. * СахНИРО Отчет по договору Y-00571 268

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Oscillatoria sp. * Spirulina sp. * * * DINОPHYTA Achradina pulchra Lohm. T-B N * Amphidinium crassum Lohm. Ar-B N * Amphidinium fusiforme Martin B * Amphidinium lacustre Stein * Amphidinium larvale Lindem. * Amphidinium operculatum Clap. et Lachm. * Amphidinium sp. * Ceratium tripos Schutt TBA P * Dinophysis acuminata Clap. et Lachm. N * * * * Dinophysis acuta Ehr. BP * * Dinophysis fortii Pav. T-B N * Dinophysis rotundata Clap. et Lachm. C P * Diplopsalis lenticula Berg C N * Glenodinium sp. * Gonyaulax digitalis (Pouch.) Kof. T-B N * Gonyaulax sp. * * Gymnodinium agiliforme Schill. T-B N * * Gymnodinium albulum Lind * * * Gymnodinium blax Harris * * Gymnodinium japonica Hada * Gymnodinium sanguineum Hirasaka N * * Gymnodinium simplex (Lohm.) Kor.et Sw Ar-B N * * Gymnodinium sp. * * Gymnodinium wulffii Schill. N * Gyrodinium flagellare Shill B * Gyrodinium fusiforme Kof.et Sw. T-B P * СахНИРО Отчет по договору Y-00571 269

Bays Taxon Geography Ecology Piltun Chaivo Nyisky Nabil Lunsky Gyrodinium spirale (Bergh) Kof. et Sw. C P * Heterocapsa triquetra (Ehr.) Stein B N * * * * Katidinium rotundatum (Lohm.) Loeblich T-B N * * * * Katodinium fungiforme (Aniss) Loeblich * Katodinium glaucum (Lebour) Loeblich T-B P * Noctiluca scintillans (Macart.) Kof. et Sw. C N * Oblea baculifera Balech * * Oblea rotunda (Lebour) Balech ex Sournia * * * Oxytoxum variabile Schill. T O * Prorocentrum balticum (Lochm.) Loeblich C N * Prorocentrum micans Ehr. C N * Protoceratium reticulatum (Clap. et Lachm.) Butsch B-Ar N * Protoperidinium brevipes (Pauls.) Balech. B-Ar N * Protoperidinium crassipes (Kof.) Balech O and N * Protoperidinium curtipes (Jorg.) Balech O * Protoperidinium leonis (Pav.) Balech C N * Protoperidinium pallidum (Ostf.) Balech O * Protoperidinium pellucidum Bergh. N * Protoperidinium sp. * Protoperidinium subinerme (Pauls.) Loeblich N * Scrippsiella trochoidea (Stein) Loeblich * Thecadinium kofoidii (Herdman) Schill. * * * EUGLENOPHYTA Euglena sp. * * * * * Eutreptia globulifera Van Goor. * * * * * Eutreptia lanowii Steuer * * * * Phacus sp. * RAPHYDOPHYTA Heterosigma sp. * * СахНИРО Отчет по договору Y-00571 270

Notes to Appendix 2.6.1: Geography – Phytogeographic characteristic: C – cosmopolite, T-B – tropical-boreal, B - boreal, A-B – arctic-boreal, B-A – boreal-arctic, TBA – tropical-boreal-arctic, B-T – boreal-tropical, А – arctic, BP - bipolar, T-An – tropical-antarctic. Ecology – Ecological characteristic: N - neritic, P - pantalass, O - oceanic.

Appendix 2.6.2 Quantitative indices of phytoplankton development in the northeastern Sakhalin lagoons in September 2002 (N – numbers, thousand cell/l, В –biomass, mg/m3)

Piltun Bay Raphydophy № st Total Diatomeae Chlorophyta Chrysophyta Cryptophyta Cyanophyta Dinophyta Euglenophyta ta N B N B N B N B N B N B N B N B N B 1(0) 392,392 39,78 12,141 15,39 148,504 19,9 - - - - 231,329 3,41 0,209 0,88 0,209 0,2 - - 2(0) 2061,154 516,3 71,151 14,46 1119,619 637,14 0,478 6,75 15,312 2,36 831,58 50,06 15,358 95,46 7,656 2,89 - - 3(0) 144,108 24,83 14,879 11,94 35,217 1,84 0,314 0,08 0,943 0,14 91,183 1,36 1,572 9,47 - - - - 4(0) 1020,005 901,87 263,899 235,78 80,755 4,04 2,718 38,41 15,53 5,2 459,681 19,93 195,869 597,5 3,106 1,17 - - 5(0) 201,283 431,67 164,235 194,12 35,566 236,89 - - 0,741 0,39 - - - - 0,741 0,28 - - 6(0) 529,389 39,58 40,895 31,86 8,095 0,36 0,016 0,07 1,722 0,6 478,564 6,06 0,081 0,63 0,016 0,01 - - 7(0) 211,238 235,51 181,526 219,15 9,905 6,4 0,943 0,53 14,148 4,178 0,943 0,11 - - 3,773 5,05 0,943 0,4 8(0) 1913,581 283,35 251,711 53,29 1136,711 84,56 - - 452,9 81,45 40,159 4,54 25,965 57,2 6,135 2,31 - - 9(0) 522,968 672,51 123,446 584,29 19,139 0,7 2,871 14,04 28,708 9,26 327,273 30,81 13,875 30,53 7,656 2,89 - - 10(0) 331,222 266,92 110,088 153,94 15,748 0,79 - - 107,614 37,44 73,493 0,29 21,326 73,28 2,953 1,18 - - 11(0) 885,765 498,31 45,193 58,69 124,976 3,97 1,531 21,63 3,828 1,71 576,841 7,363 125,741 402,0 6,124 2,31 1,531 0,64 Chaivo Bay 1(0) 58,365 45,81 46,32 43,74 - - - - 12,03 1,8 0 0 0,015 0,26 - - - - 2(0) 75,231 45,64 60,265 52,51 - - - - 21,435 4,7 0 0 - - 8,038 7,57 - - 3(0) 84,024 60,4 45,758 33,36 1,203 0,06 - - 14,436 3,06 0,902 0,102 - - 7,218 4,68 - - 3(5) 77,58 73,92 50,922 60,61 - - - - 20,438 7,34 0 0 - - 6,22 5,97 - - 4(0) 47,708 42,88 37,127 39,23 - - - - 9,405 2,5 0 0 - - 1,176 1,152 - - 4(4,5) 41,039 234,32 35,57 229,8 - - - - 1,094 0,39 0 0 - - 4,375 4,13 - -

СахНИРО Отчет по договору Y-00571 271

5(0) 91,714 47,45 42,951 38,26 - - - - 23,787 6,5 24,183 1,917 - - 0,793 0,77 - - 5(4,5) 50,712 108,27 50,631 108,2 ------0,081 0,08 - - 6(0) 121,56 596,3 117,241 590,93 - - 0,859 0,23 1,718 0,27 - - 0,883 4,06 0,859 0,81 - - 7(0) 217,141 291,98 217,141 291,98 ------8(0) 22,258 28,68 22,258 28,68 ------9(0) 174,704 309,42 174,704 309,42 ------Nyisky Bay 1(0) 2186,909 2106,88 41,044 62,15 294,136 33,2 - - 27,669 9,56 7,519 0,096 1,203 0,3 1815,338 2001,57 - - 2(0) 19,762 20,96 15,113 18,01 - - 0,465 0,13 3,719 0,9 - - 0,465 1,92 - - - - 3(0) 36,813 84,26 27,462 82,77 1,558 0,18 - - 7,403 1,11 - - 0,39 0,2 - - - - 4(0) 47 110,81 34,47 89,06 0,533 0,12 1,866 10,49 8,797 1,88 - - 1,334 9,26 - - - - 4(2,5) 6,123 10,44 4,469 9,6 - - - - 1,504 0,7 - - - - 0,15 0,15 - - 5(0) 50,105 85,35 37,392 81,33 - - - - 12,303 3,89 - - 0,41 0,13 - - - - 6(0) 116,855 296,28 77,199 284,0 - - - - 38,852 11,82 - - 0,011 0,37 - - - - 7(0) 31,568 41,58 28,411 41,07 0,861 0,04 - - 4,019 1,73 0,861 0,074 ------7(4,5) 69,423 363,95 63,065 354,83 0,424 0,02 0,424 5,99 5,086 2,98 - - 0,424 0,13 - - - - 8(0) 58,284 137,93 29,041 133,58 1,06 0,06 0,636 2,67 26,487 7,06 - - 0,636 7,22 0,848 0,9 - - 8(6) 89,2 331,13 74,264 312,63 - - 0,025 0,11 13,533 2,2 - - 0,476 15,28 0,902 0,91 - - 9(0) 114,981 161,48 70,197 137,8 - - 1,722 8,42 34,45 11,92 - - - - 8,612 3,34 - - 10(0) 193,956 231,72 138,836 204,28 - - - - 55,12 27,44 ------11(0) 88,879 145,81 50,554 141,38 - - - - 9,043 3,87 27,56 0,11 - - 3,014 1,14 - - 12(0) 37,158 61,42 27,684 56,76 1,292 0,16 - - 6,459 3,66 - - - - 2,584 0,97 - - 12(3) 34,625 50,47 22,324 44,35 0,546 0,16 - - 9,022 4,02 - 1,093 0,29 1,64 1,66 - - Nabil Bay 1(0) 28,386 61,78 17,52 58,64 2,625 0,14 - - 6,999 1,05 0,192 0,02 0,875 1,76 0,175 0,17 - - 1(7) 90,592 351,25 60,174 339,86 0,342 0,01 0,342 1,44 17,772 4,83 10,253 0,19 1,367 4,92 0,684 0,66 - - 2(0) 56,894 144,91 31,439 134,91 1,675 0,08 0,239 1,0 21,771 6,54 0,813 0,05 0,957 2,32 - - - - 2(5) 60,924 125,7 57,042 117,26 - - 1,941 8,15 1,941 0,29 ------3(0) 86,872 224,22 67,552 212,43 7,792 0,86 1,64 6,89 9,022 3,03 - - 0,046 0,18 0,82 0,83 - - 4(0) 3074,556 3292,21 48,031 44,23 5,195 0,59 - - 114,286 17,01 1870,13 33,66 1021,31 3182,0 15,598 14,69 - - 5(0) 495,961 333,32 354,143 244,63 76,773 10,7 - - 37,321 15,86 - - 19,194 54,11 8,53 8,04 - - 6(0) 31,081 9,27 17,753 8,06 6,931 0,35 - - 1,599 0,32 4,27 0,04 - - 0,533 0,5 - - 6(1,8) 44,367 39,92 44,367 39,92 - - - - 0 0 ------СахНИРО Отчет по договору Y-00571 272

7(0) 400,41 280,08 349,268 262,17 9,406 0,99 - - 34,095 6,1 1,76 0,12 2,351 7,38 3,527 3,32 - - 7(1,2) 146,888 204,47 140,976 202,97 1,367 0,06 - - 2,734 0,98 0,44 0,05 1,367 0,41 - - - - 8(0) 8,306 4,42 4,43 1,77 0,923 0,05 - - 2,03 0,92 - - 0,369 1,16 0,554 0,52 - - 9(0) 2361,616 502,72 121,164 102,1 488,312 27,75 - - 17,99 2,7 1734,15 370,18 ------9(2) 108,669 37,98 19,242 27,46 44,702 2,16 - - 13,534 3,55 30,76 3,03 0,433 1,79 - - - - Lunsky Bay 1(5) 101,388 125,58 47,369 75,7 6,234 0,97 0,007 0,03 38,961 15,65 0,519 0,002 8,318 33,28 - - - - 2(0) 551,417 396,61 181,984 232,6 23,397 2,86 1,558 6,54 261,818 123,62 - - 4,738 1,5 77,922 29,48 - - 3(0) 281,206 409,75 19,095 18,99 16,422 2,49 3,483 39,32 238,852 64,37 - - 3,354 284,51 - - - - 3(2) 409,002 631,06 37,027 118,59 54,125 7,45 13,255 37,5 300,721 84,95 - - 3,322 382,21 0,552 0,36 - - 4(0) 200,12 698,32 197,927 671,4 ------1,14 26,29 - - 1,053 0,64 5(0) 585,32 424,89 35,564 69,19 - - - - 529,542 221,46 - - 3,236 111,1 0,246 0,23 - - 5(3) 461,543 158,74 35,714 27,77 12,085 1,66 2,844 19,01 408,038 99,61 - - 2,862 10,7 - - - - 6(0) 1023,705 851,29 1014,135 844,09 - - 0,342 1,44 8,886 4,17 - - 0,342 1,6 - - - - 7(0) 7,536 7,88 4,177 7,205 0,191 0,05 0,005 0,02 3,062 0,46 - - 0,101 0,14 - - - - 8(0) 358,212 962,17 32,777 23,7 0,689 0,08 0,344 4,86 23,426 4,02 0,172 0,019 298,737 928,22 2,067 1,28 - - 9(0) 121,609 61,06 27,752 28,82 15,639 1,67 1,564 0,42 74,286 26,51 - - 2,368 3,64 - - - -

СахНИРО Отчет по договору Y-00571 273

Appendix 2.7.1. A list of zooplankton species and forms found in the bays in 2002 N GROUP Species, form Ecology 1 PROTOZOA Tintina sp. Euplankton 2 Notholca acuminata Euplankton 3 ROTATORIA Synchaeta sp. Euplankton 4 Euchlanis lucksiana Euplankton 5 COELENTERATA Obelia longissima Meroplankton 6 TUNICATA Fritilaria borealis Euplankton 7 POLYCHAETA Polychaeta indet., larvae Meroplankton 8 Evadne nordmanni Euplankton 9 CLADOCERA Podon leuckarti Euplankton 10 Chydorus sp. Euplankton 11 Sinocalanus tenellus Euplankton 12 Neocalanus plumchrus Euplankton 13 Pseudocalanus newmani Euplankton 14 Schmackeria inopina Euplankton 15 Eurytemora pacifica Euplankton 16 Eurytemora con. raboti Euplankton 17 Eurytemora asymmetrica Euplankton 18 Eurytemora herdmani Euplankton 19 Acartia longiremis Euplankton COPEPODA 20 Acartia clausi Euplankton 21 Tortanus discaudatus Euplankton 22 Tortanus derugini Euplankton 23 Centropages abdominalis Euplankton 24 Halicyclops sp. Euplankton 25 Oithona similis Euplankton 26 Harpacticoidae indet. Planktobenthos 27 Ergasilus sp. Meroplankton 28 Nauplii copepoda Euplankton 29 Cypris. cirripedia Meroplankton CIRRIPEDIA 30 Nauplii cirripedia Meroplankton 31 HYDRACARINA Hydracarina indet Planktobenthos 32 Bivalvia, larvae Meroplankton MOLLUSCA 33 Limacina helicina Euplankton

СахНИРО Отчет по договору Y-00571 274 Appendix 2.7.2 Quantitative characteristics of zooplankton of the first complex Nauplii copepoda Deviation Deviation N, of the B, of the Biom Status Form Group F ID ind./m3 mean mg/m3 mean ass, % value value Nauplii Dominant Copepoda 22886,1 2106,444 114,43 10,53222 45,5 100,0 4548,70 copepoda Total 1 - 22886,1 1255,998 114,43 6,27999 45,5 4548,70 dominants Typical for I Acartia sp. Copepoda 4367,5 750,366 31,14 5,24530 12,4 70,6 873,90 order Typical for I Eurytemora Copepoda 3524,6 443,513 24,86 3,07630 9,9 82,4 813,70 order sp. Typical for I Acartia Copepoda 837,8 148,454 23,29 4,17464 9,3 58,8 544,47 order clausi Typical for I Oithona Copepoda 2819,0 266,468 12,84 1,26414 5,1 64,7 330,21 order similis Typical for I Synchaeta Rotatoria 8784,2 1703,869 24,60 4,77083 9,8 17,6 172,53 order sp. Total of typical for I 5 - 20333,1 0,000 116,72 7,99550 46,4 - 2734,82 order Typical for II Sinocalanus Copepoda 98,7 11,396 2,97 0,38108 1,2 47,1 55,48 order tenellus Typical for II Eurytemora Copepoda 56,6 6,731 4,66 0,55290 1,9 29,4 54,47 order herdmani Typical for II Evadne Cladocera 159,9 37,315 3,20 0,74631 1,3 11,8 14,95 order nordmanni Typical for II Harpacticoi Copepoda 39,7 4,226 0,95 0,10142 0,4 35,3 13,37 order dae indet. Total of typical for II 4 - 354,9 21,936 11,78 0,61674 4,7 - 138,27 order Secondary for Tintina sp. Protozoa 2126,7 371,216 2,13 0,37122 0,8 11,8 9,95 I order Secondary for Eurytemora Copepoda 77,1 18,688 2,85 0,69147 1,1 5,9 6,67 I order pacifica Secondary for Podon Cladocera 50,1 9,586 0,90 0,17255 0,4 11,8 4,22 I order leuckarti Secondary for Eurytemora Copepoda 20,6 4,993 1,79 0,43514 0,7 5,9 4,20 I order con. raboti Secondary for Acartia Copepoda 13,6 2,279 0,68 0,11396 0,3 11,8 3,18 I order longiremis Secondary for Obelia Coelentera 13,5 2,813 0,27 0,05626 0,1 11,8 1,26 I order longissima ta Total of secondary for I 6 - 2301,5 215,966 8,62 0,68834 3,4 - 29,46 order Secondary for Bivalvia, Mollusca 1,5 0,357 0,01 0,00357 0,0 5,9 0,03 II order larvae Secondary for Fritilaria Tunicata 1,9 0,467 0,00 0,00107 0,0 5,9 0,01 II order borealis Total of secondary for 2 - 3,4 0,310 0,02 0,00197 0,0 - 0,04 II order Total 18 - 45878,9 2639,503 251,57 14,83394 100,0 - 7451,29

СахНИРО Отчет по договору Y-00571 275 Appendix 2.7.3 Quantitative characteristics of zooplankton of the second complex Acartia hudsonica Deviatio Deviation Biom N, n of the B, of the Status Form Group ass, F ID ind/m3 mean mg/m3 mean % value value Acartia Dominant Copepoda 1615,0 167,855 45,32 4,62390 32,2 92,9 2990,26 hudsonica Dominant Acartia sp. Copepoda 2964,5 436,655 31,59 4,55456 22,4 100,0 2244,20 Total dominants 2 - 4579,5 305,767 76,91 4,74444 54,6 - 5234,47 Eurytemora Typical for I order Copepoda 1006,8 130,652 14,76 2,00725 10,5 78,6 824,22 sp. Eurytemora Typical for I order Copepoda 271,4 37,172 20,88 2,85320 14,8 42,9 635,79 herdmani Nauplii Typical for I order Copepoda 1769,1 289,856 8,85 1,44928 6,3 100,0 628,49 copepoda Harpacticoid Typical for I order Copepoda 228,9 18,007 5,49 0,43216 3,9 92,9 362,40 ae indet. Oithona Typical for I order Copepoda 375,1 50,744 2,21 0,30225 1,6 64,3 101,02 similis Total of typical 5 - 3651,3 0,000 52,19 3,17565 37,1 - 2551,92 for I order Typical for II Sinocalanus Copepoda 175,6 44,883 5,80 1,48098 4,1 21,4 88,37 order tenellus Typical for II Eurytemora Copepoda 66,1 13,096 2,56 0,50936 1,8 14,3 25,99 order pacifica Typical for II Pseudocalan Copepoda 13,9 1,778 0,51 0,07103 0,4 28,6 10,35 order us newmani Total of typical 3 - 255,6 22,640 8,87 0,75634 6,3 - 124,72 for II order Secondary for I Eurytemora Copepoda 4,8 0,983 0,93 0,19541 0,7 14,3 9,49 order asymmetrica Secondary for I Halicyclops Copepoda 17,9 3,864 0,84 0,18159 0,6 14,3 8,52 order sp. Secondary for I Synchaeta Rotatoria 140,3 37,510 0,39 0,10503 0,3 7,1 1,99 order sp. Secondary for I Polychaeta Polychaet 28,1 7,502 0,28 0,07502 0,2 7,1 1,42 order indet., larvae a Secondary for I Cypris. Cirripedia 3,6 0,955 0,21 0,05727 0,2 7,1 1,09 order cirripedia Total of secondary 5 - 194,6 21,776 2,66 0,15511 1,9 - 22,51 for I order Secondary for II Tintina sp. Protozoa 32,1 5,878 0,03 0,00588 0,0 14,3 0,33 order Secondary for II Schmackeria Copepoda 7,1 1,909 0,05 0,01432 0,0 7,1 0,27 order inopina Secondary for II Nauplii Cirripedia 3,6 0,955 0,02 0,00477 0,0 7,1 0,09 order cirripedia Total of secondary 3 - 42,9 3,070 0,10 0,00774 0,1 - 0,69 for II order Total 18 - 8723,8 549,000 140,74 8,50584 100,0 - 7934,31

СахНИРО Отчет по договору Y-00571 276

Appendix 2.7.4 Quantitative characteristics of zooplankton of the third complex Eurytemora herdmani + Acartia spp. Deviation Deviatio B, N, of the n of the Bioma Status Form Group mg/m F ID ind/m3 mean mean ss, % 3 value value Eurytemora 154,7 Dominant Copepoda 2019,5 294,701 22,26235 38,2 81,8 3128,52 herdmani 2 Acartia Dominant Copepoda 2511,9 546,623 70,13 15,24104 17,3 72,7 1260,46 hudsonica Dominant Acartia sp. Copepoda 5996,6 1198,828 56,03 12,41486 13,8 90,9 1258,78 10528, 280,8 Total dominants 3 - 894,835 22,31738 69,4 - 5647,76 0 7 Typical for I Eurytemora Copepoda 1893,1 191,657 40,02 6,21340 9,9 81,8 809,19 order sp. Typical for I Schmackeria Copepoda 797,7 179,607 42,35 6,12151 10,5 36,4 380,62 order inopina Typical for I Nauplii Copepoda 1581,7 212,490 7,91 1,06245 2,0 100,0 195,45 order copepoda Typical for I Sinocalanus Copepoda 618,5 146,344 19,71 4,60289 4,9 36,4 177,09 order tenellus

Total of typical 109,9 4 - 4891,0 0,000 6,34052 27,2 - 1562,36 for I order 8

Typical for II Harpacticoid Copepoda 256,9 52,589 6,17 1,26213 1,5 54,5 83,12 order ae indet. Typical for II Oithona Copepoda 728,7 164,984 3,75 0,83454 0,9 36,4 33,74 order similis

Total of typical 2 - 985,7 81,419 9,92 0,75520 2,5 - 116,86 for II order

Secondary for I Hydracarina Hydracarin 45,5 13,705 2,27 0,68525 0,6 9,1 5,11 order indet a Secondary for I Acartia Copepoda 22,7 6,853 1,14 0,34263 0,3 9,1 2,55 order longiremis Secondary for I Synchaeta Rotatoria 120,7 27,976 0,34 0,07833 0,1 18,2 1,52 order sp. Total of secondary for I 3 - 188,9 18,135 3,75 0,35538 0,9 - 9,18 order Secondary for II Notholca Rotatoria 506,1 152,596 0,10 0,03052 0,0 9,1 0,23 order acuminata Total of secondary for II 1 - 506,1 65,338 0,10 0,01307 0,0 - 0,23 order 17099, 404,6 Total 13 - 1092,798 24,83361 100,0 - 7336,39 7 2

СахНИРО Отчет по договору Y-00571 277

Appendix 2.8.1

A species list of organisms of the dredge benthos from the Piltun Bay in June-July 1999

ALGAE Enchytraeidae gen. sp. Cladophora glomerata Kutz Enchytraeus albidus Henle Enteromorpha sp. Limnodrilus grandisetosus Nomura Spirogyra sp. Limnodrilus hoffmeisteri f. typica Ulotrix implexa Kutz Claparade Pediastrum sp. Limnodrilus profundicola (Verril) Fam. sp. 1 Lumbriculus variegatus (O. F. Fam. sp. 2 Muller) Stigonema sp. Nais barbata O. F. Muller Tolypotrix sp. Nais variabilis Piguet Melosira sp. Ophidonais serpentina (O. F. Muller) MAGNOLIOPHYTA Paranais litoralis (Muller) Potamogeton perfoliatus L. Pristinella bilobata (Bretscher) (?) Potamogeton pectinatus L. Propappus volki Michaelsen Zostera japonica Aschers et Graebn Psammoryctides barbaus (Grube) (?) Zostera marina L. Rhyacodrilus coccineous Ruppia occidentalis S. Wats (Vejdovsky) Ruppia maritima L. Spirosperma apapillatus (Lastockin Myriophyllum spicatum L. et Sokolskaya) TURBELLARIA Spirosperma ferox Eisen fam. sp.1 Spirosperma nikolskyi (Lastockin et fam. sp.2 Sokolskaya) NEMATODES Spirosperma velutinus (Grube) Nematoda indet. Tubifex tubifex (O. F. Muller) Dorylainus sp. Uncinais uncinata (Oersted) Oncholoimidae gen. sp. HIRUDINEA Monhysteridae gen. sp. Erpobdella octoculata (L.) Mermitidae gen. sp. Glossiphonia complanata (L.) Jotonchus sp. MOLLUSCA Monochus sp. GASTROPODA ANNELIDES Anisus acronicus (Ferussac) POLYCHAETA Anisus stroemi (Westerlund) Sabellidae gen. sp. Cincinna sirotskii Starobogatov et Eteone longa (Fabricius) Zatrawkin Hediste japonica (Izuka) Fluviocingula nipponica Kuroda et Phyllodoce groenlandica (Oersted) Habe Spionidae gen.sp. Limnaea kurilensis Kruglov et PRIAPULIDA Starobogatov Priapulida indet. Limnaea schubinae Kruglov, SIPUNCULA Starobogatov et Zatrawkin Phascolosoma sp. Limnaea sp. OLIGOCHAETA Littorina kurila (Middendorff) Amphichaeta leydigi Tauber (?) Neritrema sitkana kurila Aulodrilus limnobius Bretseher Volutharpa sp. Chaetogaster langi Bretsher BIVALVIA Corbicula japonica

СахНИРО Отчет по договору Y-00571 278 Euglesa sp.1 HYDRACHNIDIA Euglesa sp.2 Lebertia porosa Thor. Euglesa sp.3 Tiphys sp. Euglesidae gen. sp. INSECTA Leionucula sp. TRICHOPTERA Liocyma fluctuosa aniwana (Dall) Molanna angustata Curt Macoma balthica (L.) Mystacides longicornis L. Musculium kafanovi Starobogatov Mystacides nigra L. Mya truncata (Linne) Oecetis ochracea Curtis Mytilis edulis edulis (Linne) sp.1 Pisidium decurtatum Lindh. sp.2 Potamocarbula amurensis COLEOPTERA (Schrenck) Donacia sp. Veneridae gen.sp. Haliplus sp. ARTHROPODA DIPTERA CRUSTACEA Aspectrotanypus trifascipennis COPEPODA (Zetterstedt) (?) Eurytemora gracilis (Sars) (?) Chironominae gen. sp. Harpacticoida sp. Chironomus sp.1 Nauplii sp. Chironomus sp.2 OSTRACODA Chironomus sp.3 Ostracoda indet. Cladopelma cf. lateralis MYSIDACEA Cladotanytarsus cf. mancus Archaeomysis grebnitzkii Conchapelopia sp. Czerniavsky Cricotopus cf. sylvestris Neomysis awatschensis f. Cryptochironomus cf. defectus awatschensis Brant Dicrotendipes pelochloris (Kieffer) Neomysis awatschensis f. Einfeldia sp. intermedius (Chernjavsky) Glyptotendipes glaucus (Meigen) (?) Neomysis mirabilis (Chernjavsky) Glyptotendipes gripekoveni (Kieffer) CUMACEA Glyptotendipes paripes (Edwards) Lamprops korroensis Derzhavin Kiefferelus tendipediformis AMPHIPODA (Goetghebuer) Corophium steinegeri Gurjanova Paracladius sp. Dogielinotus moskvitini (Derzhavin) Paratanytarsus sp. Eogammarus kygi Derzhavin (?) Paratendipes intermedius Eogammarus tiushovi (Derzhavin) Tschernovskij Ischyrocerus elongatus Gurjanova Polipedium (Tripodura) bicrenatum Kamaka kutchae Derzhavin Kieffer Locustogammarus hirsutimanus Procladius sp. Kurenkov et Mednicov Psectrocladius cf. barbimanus Pontogeneia sp. (Edwards) Pontoporeia affinis Lindstrom Stictochironomus cf. histrio ISOPODA Stictochironomus crassiforceps Asellus hilgendorphi Bovalius (Kieffer) Idothea ochotensis Brandt Tanytarsus verralli Goethebuer Saduria entomon (Linne)

DECAPODA Crangon septemspinosa Say

СахНИРО Отчет по договору Y-00571 279

Appendix 3.2.1. Results of hydrochemical studies in the Chaivo Bay in 2002

0 - - 3- № st. Depth, m T, С S, ‰ рН О2 , N-NO2 , N-NO3 , Р-РО4 , Si, Petroleu Suspended Chlorophyll а, mg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 m matters, mkg/dm3 products, mg/dm3 mg/dm3 1 1.0 10.0 6.8 7.95 9.25 <0.5 <5.0 15.2 578.3 <0.005 12.40 4.22 2 1.0 9.2 13.5 8.04 8.96 <0.5 <5.0 24.5 662.4 <0.005 23.06 2.80 3 5.0 9.6 20.6 8.53 9.20 1.2 <5.0 40.1 348.0 <0.005 16.46 2.48 9.8 21.3 8.47 8.43 0.8 9.0 44.6 420.8 <0.005 26.80 2.63 4 4.5 9.6 23.4 8.36 9.09 1.7 <5.0 53.0 439.1 <0.005 18.55 2.57 9.6 23.5 8.32 9.02 1.0 9.0 56.0 510.0 <0.005 23.59 3.20 5 4.5 9.4 16.6 8.45 10.80 <0.5 <5.0 49.1 1.3 <0.005 13.10 1.84 9.7 17.5 8.30 9.82 1.3 <5.0 76.5 729.4 <0.005 16.80 2.59 6 0.4 9.1 28.5 8.74 10.40 2.6 9.0 38.0 662.7 <0.005 18.86 2.88 7 1.0 7.7 21.2 8.39 11.00 <0.5 <5.0 16.8 1211.2 <0.005 10.80 2.04 8 0.6 7.9 15.6 8.02 9.82 0.6 <5.0 22.0 1699.0 <0.005 10.35 2.43 9 0.6 5.4 2.6 7.49 10.20 <0.5 <5.0 12.0 1336.2 <0.005 49.70 3.16

СахНИРО Отчет по договору Y-00571 280 Appendix 3.8.1

A species list of organisms of the dredge benthos from the Chaivo Bay in July 1999 (by “Ecological studies …”, 2001)

ALGAE ARTHROPODA Algae indet. CRUSTACEA Chaetomorpha sp. MYSIDAE MAGNOLIOPHYTA Archaeomysis grebnitzkii Zostera asiatica Czerniavsky Zostera marina CUMACEA Zostera nana Diastylis sp. NEMERTINI AMPHIPODA Lineidae indet. Anisogammaridae indet. ANNELIDES Calliopius laeviusculus Kroyer POLYCHAETA Corophiidae indet. Ampharete arctica Corophium steinegeri Gurjanova Ampharete sp. Eogammarus kygi (Derzhavin) Capitellidae indet. Eogammarus hirsutimanus Chone teres (Kurenkov et Mednikov, 1959) Eteone longa Eogammarus sp. Glycinde armigera Moore, 1911 Eogammarus tiushovi Hediste japonica Izuka (Derzhavin) Heteromastus filiformis Ischyrocerus commensalis Laonice cirrata Chevreux, 1900 Nephtys sp. Ischyrocerus sp. Nereis pelagica Photis sp. Phyllodocidae indet. Photis sp. 1 Scalibregma sp. Pontoporeia affinis Lindstrom Spio filicornis ISOPODA Spio sp. Saduria entomon (Linne) Spionidae indet. DECAPODA Terebellidae indet. Crangon septemspinosa Say Sipuncula INSECTA Phascolosoma sp. Chironomidae larvae indet. Echiuridae Echiuridae indet. OLIGOCHAETA Oligochaeta indet. MOLLUSCA GASTROPODA Cryptonatica janthostoma (Pall.) Liostomia sp. (?) BIVALVIA Liocyma fluctuosa (Gould, 1841) Macoma balthica (Linne) Mya sp. Mysella kurilensis Mytilus trossulus

СахНИРО Отчет по договору Y-00571 281

Appendix 4.2.1 Results of hydrochemical studies in the Nyisky Bay in 2002

0 - - 3- № st. Depth, m T, С S, ‰ рН О2 , N-NO2 , N-NO3 , Р-РО4 , Si, Petroleu Suspended Chlorophyll а, mg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 m matters, mkg/dm3 products, mg/dm3 mg/dm3 1 0.4 6.6 9.3 8.04 10.80 <0.5 <5.0 18.1 1535.2 <0.005 12.32 9.61 2 0.4 8.8 14.0 8.06 10.40 <0.5 <5.0 12.0 558.5 <0.005 8.05 0.93 3 0.6 9.2 15.5 8.33 10.70 <0.5 <5.0 75.3 449.8 <0.005 8.85 0.93 4 2.5 9.2 28.9 8.17 9.19 1.3 19.0 11.3 639.8 <0.005 11.10 1.24 9.4 29.4 8.20 9.26 0.9 37.0 14.7 437.0 0.010 25.07 3.10 5 0.35 11.6 22.1 8.52 12.00 <0.5 <5.0 10.1 436.0 <0.005 12.50 1.27 6 0.2 13.2 22.5 8.69 11.50 <0.5 <5.0 22.0 455.2 <0.005 10.75 0.90 7 4.5 9.2 10.8 8.36 10.10 <0.5 38.0 6.0 703.0 <0.005 8.30 1.30 9.6 20.8 8.44 8.99 1.3 15.0 46.8 1387.5 <0.005 14.30 1.81 8 6.0 9.6 22.1 8.25 9.67 1.9 14.0 25.2 1568.0 <0.005 12.30 1.89 9.6 26.7 8.23 9.20 1.1 14.0 8.0 531.6 <0.005 33.13 3.28 9 0.7 9.5 11.1 8.40 10.10 0.7 6.0 39.0 816.5 <0.005 12.95 2.01 10 0.8 10.9 7.6 8.50 11.20 <0.5 7.0 9.1 1088.2 <0.005 16.71 3.08 11 0.4 10.0 2.4 7.67 10.30 <0.5 29.0 9.6 1776.4 <0.005 7.80 0.68 12 3.0 10.1 5.5 7.94 10.40 <0.5 26.0 7.1 879.0 <0.005 9.78 0.95 10.2 6.9 7.95 10.30 <0.5 24.0 9.0 1424.6 <0005 15.23 1.48

СахНИРО Отчет по договору Y-00571 282

Appendix 4.8.1 A species list of organisms of the dredge benthos from the Nyisky Bay in July 1999

Algae Limnodrilus profundicola (Verril, 1871) Chaetomorpha linum Lumbucillus lineatus (?) Enteromorpha sp. Ophidonais serpentina (O. F. Muller, Magnoliophyta 1773) Potamogeton perfoliatus L. Paranais litoralis Potamogeton pectinatus L. Propappus volki Michaelsen, 1915 Zostera japonica Aschers et Graebn Spirosperma apapillatus (Lastockin et Zostera marina L. Sokolskaya, 1953) Nematoda Spirosperma ferox Eisen, 1879 Nematoda indet. Spirosperma heterochaetus Annelides Spirosperma nikolskyi (Lastockin et Polychaeta Sokolskaya, 1953) Ampharete arctica Malmgren, 1865 Spirosperma velutinus (Grube, 1879) Arenicola sp. Tubifex tubifex (O. F. Muller, 1773) Chone cincta Zachs, 1933 Uncinais uncinata (Oersted, 1842) Eteone longa Fabricius, 1780 Hirudinea Glycera capitata Hirudinea indet. Glycinde armigera Moore, 1911 Mollusca Halicriptus sp. Gastropoda Hediste japonica Izuka, 1908 Epheria turrita Maldanidae g. sp. Fluviocingula sp. Nephthys caeca Muller, 1776 Gastropoda fam. sp. Nereidinae g. sp. Littorina sitkana Nereis vexillosa Grube, 1849 Margarites sp. Nicomache sp. Bivalvia Pectinaria brevicoma Johnson Bivalvia fam. sp. (juv.) Phyllodoce groenlandica var. orientalis Liocyma fluctuosa Gould, 1841 Zachs Macoma balthica Linne, 1758 Poluchaeta fam. sp. Mya sp. Polydora quadrilobata Jakobi Mytilus edulis Linne, 1758 Prionospio sp. Arthropoda Pygospio elegans Claparede Crustacea Rhodine loveni COPEPODA Sabellidae sp. Copepoda indet. Scololepis sp. OSTRACODA Spio filicornis O. Muller, 1776 Ostracoda var. Spionidae g. sp. MYSIDAE Syllidae g. sp. Archaeomysis grebnitsky Chernjavsky, Sipuncula 1882 Sipunculida indet. Neomysis awatschensis (Brandt, 1851) Oligochaeta Neomysis mirabilis (Chernjavsky, 1882) Enchytraeus albidus CUMACEA Limnodrilus hoffmeisteri f. typica Diastylpsis dawsoni f. calmani Derzhavin, Claparede, 1862 1926

СахНИРО Отчет по договору Y-00571 283 Lamprops korroensis Derzhavin, 1923 DECAPODA AMPHIPODA Crangon septemspinosa Say, 1818 Calliopius sp. Insecta Caprella cristibrachium Mayer, 1903 (?) DIPTERA Corophium cf. steinegeri Gurjanova, 1951 Chironominae g. sp. Dogielinotus moskvitini (Derzhavin, 1930) Chironominae g. sp. 2 Eogammarus schmidti Derzhavin, 1927 Cladopelma lateralis (Goetghebuer, 1934) Eogammarus sp. Cladotanytarsus cf. mancus Eogammarus tiuschovi (Derzhavin, 1927) Cricotopus cf. sylvestris Ischyrocerus sp. Cryptochironomus gr. defectus Kamaka kuthae Derzhavin, 1923 Dicrotendipes pelochloris (Kieffer, 1912) Nototropis collingi Gurjanova, 1938 (?) Einfeldia sp. Pararpinia sp. Einfeldia sp. 2 Pontocrates arenarius (Bate, 1858) Glyptotendipes glaucus (Meigen, 1818) Spasskogammarus spasskii (Bulytscheva, Glyptotendipes paripes (Edwards, 1929) 1952) Paratanytarsus sp. ISOPODA Paratendipes intermedius Tshernoskiy, Idothea ochotensis Brandt, 1857 1949 Saduria entomon f. orientalis (Gurjanova, Polypedium bicrenatum Kieffer, 1921 1933) Psectrocladius cf. barbimanus Synidotea bicuspidata (Owen, 1839) Tanytarsus medius Reiss et Fittkau, 1971 Tanytarsus verralli Goetghebuer, 1928

СахНИРО Отчет по договору Y-00571 284

Appendix 5.2.1 Results of hydrochemical studies in the Nabil Bay in 2002

0 - - 3- № st. Depth, m T, С S, ‰ рН О2 , N-NO2 , N-NO3 , Р-РО4 , Si, Petroleu Suspended Chlorophyll а, mg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 m matters, mkg/dm3 products, mg/dm3 mg/dm3 1 7.0 10.0 22.1 8.07 9.45 1.1 16.0 30.1 1023.0 0.005 16.80 1.85 10.6 23.7 8.00 8.97 1.9 16.0 24.0 354.2 0.012 15.90 2.34 2 5.0 11.0 20.5 8.17 8.93 <0.5 12.0 12.3 580.0 0.006 13.60 2.08 11.5 22.0 8.12 8.77 1.0 13.0 28.7 279.2 <0,005 18.55 2.17 3 0.8 10.3 21.1 8.21 9.16 1.2 18.0 40.1 387.2 <0,005 16.19 2.08 4 0.6 12.4 14.4 9.17 11.00 <0.5 <5.0 11.0 203.5 <0,005 8.65 6.20 5 0.3 11.4 16.4 8.45 9.33 <0.5 10.1 14.2 1283.4 <0,005 20.44 5.00 6 1.8 11.3 11.5 8.13 11.33 <0.5 25.4 10.2 1660.3 <0,005 9.50 2.83 10.6 12.8 8.08 8.32 <0.5 <5.0 21.3 967.2 <0,005 6.35 3.48 7 1.2 11.2 9.9 7.10 11.60 <0.5 <5.0 19.4 1057.6 <0,005 46.05 0.58 11.7 12.5 6.80 9.12 <0.5 <5.0 21.9 527.4 <0,005 2.35 3.40 8 0.8 10.5 2.4 9.17 9.30 0.6 14.2 27.5 894.2 0.005 10.94 1.88 9 2.0 10.5 14.6 8.16 10.5 <0.5 <5.0 9.0 484.3 0.030 11.85 0.59 10.6 15.0 8.12 10.0 <0.5 <5.0 13.1 352.2 <0,005 12.00 0.65

СахНИРО Отчет по договору Y-00571 285

Appendix 5.8.1 A species list of organisms of the dredge benthos from the Nabil Bay in June 1999 (by “Ecological studies …”, 2001)

ALGAE BIVALVIA Chaetomorpha sp. Liocyma fluctuosa (Gould, 1841) MAGNOLIOPHYTA Macoma balthica (Linne) Zostera asiatica Macoma calcarea (Gmelin, 1790) Zostera marina Musculista senchousia Zostera nana Mytilus trossulus COELENTERATA Potamocarbula amurensis (Schrenck) Actiniaria indet. ARTHROPODA NEMATHELMINTHES CRUSTACEA NEMATODA MYSIDAE Mermitidae indet. Archaeomysis grebnitzkii Czerniavsky NEMERTINI CUMACEA Lineidae indet. Diastylis sp. ANNELIDES AMPHIPODA POLYCHAETA Anisogammaridae indet. Ampharete arctica Caprella sp. Ampharete sp. Corophiidae indet. Ampharetidae gen. sp. (juv) Corophium steinegeri Gurjanova Capitella capitata (Fabricius, 1870) Eogammarus kygi (Derzhavin) Capitellidae indet. Eogammarus tiushovi (Derzhavin) Chone teres Photis sp. Cistendis brevicoma Photis sp. 1 Cistendis granulata Pontoporeia affinis Lindstrom Dipoydora sp. ISOPODA Glycera capitata (Oersted, 1923) Idothea ochotensis Brandt Glycera sp. Saduria entomon (Linne) Glycinde armigera Moore, 1911 Synidotea bicuspida Heteromastus sp. DECAPODA Nephtys caeca Crangon septemspinosa Say Nephtys sp. Pagurus middendorfii Nereis sp. INSECTA Onuphis sp. Chironomidae larvae indet. Polychaeta indet. SIPUNCULA Phascolosoma sp. OLIGOCHAETA Oligochaeta indet. HIRUDINEA Hirudinea indet. MOLLUSCA GASTROPODA Cryptonatica janthostoma (Pall.) Liostoma sp. (?) Odostomia sp.

СахНИРО Отчет по договору Y-00571 286

Appendix 6.2.1 Results of hydrochemical studies in the Lunsky Bay in 2002

0 - - 3- № st. Depth, m T, С S, ‰ рН О2 , N-NO2 , N-NO3 , Р-РО4 , Si, Petroleu Suspended Chlorophyll а, mg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 mkg/dm3 m matters, mkg/dm3 products, mg/dm3 mg/dm3 1 0.6 11.7 27.6 9.05 11.8 <0,5 <5.0 23.1 637.4 0.009 10.40 1.58 2 0.4 13.3 17.2 8.57 11.4 1.0 8.1 62.0 553.0 <0,005 16.60 8.52 3 2.0 11.0 28.5 8.33 9.05 1.2 5.0 54.0 738.0 <0,005 12.00 4.98 9.7 29.7 8.19 8.63 0.8 8.4 59.2 744.2 <0,005 9.65 0.62 4 0.5 12.5 29.4 9.01 12.4 0.5 <5.0 55.5 455.8 <0,005 10.17 4.44 5 3.0 10.2 15.4 8.14 8.97 0.6 7.1 23.5 898.0 <0,005 37.30 2.99 10.4 27.7 8.0 9.62 1.0 6.4 16.0 1480.1 <0,005 11.90 2.50 6 0.4 13.1 11.9 8.95 11.7 <0,5 <5.0 54.3 461.0 0.005 9.45 1.27 7 0.6 13.2 22.8 8.6111 11.2 <0,5 <5.0 70.0 389.0 <0,005 7.90 1.56 8 0.5 13.6 5.7 8.67 10.5 <0,5 <5.0 43.8 1615.1 <0,005 14.50 0.35 9 0.4 13.0 4.1 9.0 10.4 0.8 <5.0 37.0 816.0 <0,005 9.70 1.61

СахНИРО Отчет по договору Y-00571 287 Appendix 6.8.1 A species list of organisms of the dredge benthos from the Lunsky Bay in July 2001 (by Latkovskaya et al., 2002)

PROTOZOA Spio filicornis Muller, 1776 SARCODINA Spio indet. FORAMINIFERA Spionidae indet. Foraminifera indet. Terebellidae indet. COELENTERATA SIPUNCULA HYDROZOA Phascolosoma indet. Hydrozoa indet. OLIGOCHAETA ACTINIARIA Oligochaeta indet. Actiniaria indet. HIRUDINEA NEMATHELMINTHES Ichtyobdellidae indet. NEMATODES Piscicola sp. Nematodes indet. Piscicolidae indet. NEMERTINI Archaeobdella esmonti Grimm, 1876 Nemertini indet. MOLLUSCA ANNELIDES GASTROPODA POLYCHAETA Cylichna sp. Ampharete arctica Malmgren, 1865 Epheria turrita A. Adams Ampharetidae indet. Falsicingula indet. Anobothurus gracilis Malmgren, 1865 Gastropoda indet. Arenicola claparedii Levinsen Littorina kurila Middendorff Capitella capitata Fabricius, 1870 Litorina squalida Broderip et Sowerby Capitellidae gen. sp. 1 Oenopota sp. Capitellidae gen. sp. 2 Retusa sp. Chone cincta Zachs, 1933 BIVALVIA Eteone longa Fabricius, 1780 Liocyma fluctuosa Gould, 1841 Eteone ornate Grube, 1877 Macoma balthica Linne, 1758 Eteone indet. Musculista senhousia Benson, 1842 Euchone olegi Zachs, 1933 Mya sp. Glycera capitata Oersted, 1843 Mytilus trossulus Gould, 1850 Glycinde armigera Moore, 1911 ARTHROPODA Hediste japonica Izuka1 CRUSTACEA Nereis zonata tigrina Zachs, 19332 CIRRIPEDIA Nereis vexillosa Grube, 1849 Balanus indet. Notomastus sp. MYSIDACEA Paraonis gracilis Tauber, 1879 Neomysis awatschensis (Brandt, 1851)3 Pectinaria soldatovi Annenkova, 1929 Neomysis mirabilis (Chernjavsky, 1882)4 Pectinaria indet. CUMACEA Polydora quadrilobata Jakobi, 1883 Diastylis bidentata Calman, 1912 Polydora indet. Lamprops korroensis Derzhavin, 1923 Polynoidae indet. AMPHIPODA Prionospio steenstrupi Malmgren, 1867 Allorchestes angusta Dana, 1856 Sabellidae indet. Anisogammarus pugettensis Dana, 1853 Calliopius laeviusculus (Kröyer, 1838)

1 In original - Nereis sakchalinensis Okuda, 1935; the last nomen is a late synonym of Hediste japonica 3 In original - Neomysis awatschensis Derzhavin, Izuka 1923 2 In original - Nereis tigrina Zachs, 1933 4 In original - Neomysis czernjawskii Derzhavin

СахНИРО Отчет по договору Y-00571 288 Corophium acherusicum Costa, 1857 Corophium crassicorne Bruzelius, 1859 Corophium indet. Corophium steinegeri Gurjanova, 1951 Eogammarus kygi (Derzhavin, 1923) Eogammarus schmidti (Derzhavin, 1927) Eogammarus indet. Fam. gen. sp. 1 Fam. gen. sp. 2 Fam. gen. sp. 3 Fam. gen. sp. 4 Fam. gen. sp. 5 Gammaridae gen. sp. 1 Gammaridae gen. sp. 2 Gammaridae gen. sp. 3 Jassidae gen. sp. 1 Jassidae gen. sp. 2 Kamaka kuthae Derzhavin, 1923 Kamaka indet. Orchestia ochotensis Brandt, 1851 Photis reinhardi Kröyer, 1842 Photis indet. Pleustidae gen. sp. Pleusymtes vasinae Budnikova, 1995 Protomedeia popovi Gurjanova, 1951 Talitridae gen. sp. 1 Talitridae gen. sp. 2 ISOPODA Idotea ochotensis Brandt, 1857 Saduria entomon Linne Synidotea bicuspidate Owen, 1839 Syidotea laevis Synidotea indet. DECAPODA Crangon septemspinosa Say, 18185 Fam. indet. (juv.) CHELICERATA HYDRACHNIDIA Hydrachnidia indet. INSECTA DIPTERA Chironomidae indet. (larvae) ECHINODERMATA HOLOTHURIOIDEA Holothurioidea indet.

5 In original - Crangon septemspinosa Stimpson

СахНИРО Отчет по договору Y-00571