DOCSLIB.ORG

An Industrial Survey for Associated Species

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

FISHING FOR KNOWLEDGE An industrial survey for associated species Report of Project Phase I by Anne Doeksen and Karin van der Reijden A collaboration between The North Sea Foundation & IMARES Commissioned by EKOFISH Group June 2014 Content 1 Introduction ......................................................................................................................... 3 2 Fisheries Management for associated stocks ............................................................................. 4 2.1 Management of associated species ................................................................................. 4 2.2 Managing associated species under the new CFP .............................................................. 8 2.3 Key insights and Conclusive points ............................................................................... 10 3 Stock assessments ............................................................................................................. 12 3.1 How to do a stock assessment ..................................................................................... 12 3.2 Surveys for stock assessment ...................................................................................... 13 3.3 Data availability and knowledge gaps for associated species ............................................. 14 3.4 Key insights and concluding points ............................................................................... 15 4 References ........................................................................................................................ 17 Appendix 1 ............................................................................................................................. 18 Appendix 2 ............................................................................................................................. 19 Appendix 3 ............................................................................................................................. 20 2 1 Introduction In 2009 the Ekofish twinrig fishery for plaice was certified to the Marine Stewardship Council’s (MSC) standard for sustainable and well-managed fisheries. Besides plaice, this fishery lands several bycatch species, in particular dab, lemon sole, brill and turbot. Ekofish wishes to have these bycatch species assessed under Principle 1 of the MSC standard and certified as part of the same unit of certification as the twinrig fishery for plaice. These species qualify as typical bycatch species, having very little directed fishing activity, and are classified as ‘associated’ or ‘Category 11’ species under the CFP. For these Category 11 species there is no management plan or comprehensive harvest strategy due to the lack of data and information required to carry out an analytical stock assessment. This presents an obstacle for getting these species assessed and certified under Principle 1 of the MSC standard. To address the data-deficiencies of Category 11 species IMARES explored options to improve data collection efforts for these species in 2011, recommending commercial catch surveys as an option to improve data collection. Following from this Ekofish has taken the lead and has initiated a pilot data- collection project, in which commercial catch data will be collected aboard their twinrig vessels during one season for the species dab, lemon sole, turbot, and brill. The aim of this pilot project is to progress towards science-based management and MSC certification of the mentioned species. This project is carried out in collaboration with the NSF and IMARES. Phase one of this project explores the hurdles and the opportunities for fisheries management and stock assessment for the North Sea species brill, turbot, lemon sole and dab. This will help identify next steps and inform the design of the commercial survey to be carried out in the subsequent phases of the project. The main question in this phase is: What are the hurdles and opportunities for fisheries management and stock assessment for North Sea brill, turbot, lemon sole and dab? This question is addressed in two subsequent chapters: chapter two reviews fisheries management. Chapter three reviews stock management. 3 2 Fisheries Management for associated stocks This chapter reviews the main obstacles and opportunities for fisheries management of North Sea brill, dab, lemon sole and turbot. Central to this chapter is the question: What are the current obstacles for fishery management of associated species brill, dab, lemon sole and turbot? What perspectives does the new Common Fisheries Policy provide? This central question is broken down in into two sub-questions: 1. How are associated species currently managed? This question reviews EU regulation and policy documents and sets out the main management instruments and requirements. It also reviews data collection and management requirements under the Common Fisheries Policy (CFP). 2. Which changes in management does the new Common Fisheries Policy foresee? This question reviews the changes to fisheries management that the adoption of the new Common Fisheries Policy (EU Regulation 1380/2013) implies. This regulation replaces the former CFP and has reformed fisheries policy in several fundamental ways, with implications for how mixed fisheries and associated species are to be managed in future. The chapter is composed around these two questions (section 2.1 and 2.2) and closes with a conclusion, a reflection on the central research question (section 2.3). 2.1 Management of associated species The main policy instrument that European fisheries are managed under is the European Union’s Common Fisheries Policy (CFP). The Common Fisheries Policy establishes a set of rules that controls EU fishing fleets and manages fish stocks in EU waters. The CFP was implemented in 1983 has been reviewed every 10 years. The most recent review, in 2013, has led to major CFP reform. This new CFP, EU Regulation 138/2013, replaces EU Regulation 2371/2002 and came into effect on January 2014. The following section (2.1) describes the fisheries management situation for brill, dab, lemon sole and turbot as it was at the time of project initiation (2013), so prior to the implementation of the new CFP. To provide a context, this section begins with a brief description of the fisheries in which these species are caught (2.1.1). Management of these fisheries will be discussed in the remaining sections (2.1.2 and 2.1.3). 2.1.1 The fisheries Brill (griet) Brill (scomthalmus rhombus) in the North Sea, Skagerrak, English Channel (ICES Areas IV, IIIa and VIIde) are considered to belong to the same biological stock. Brill in this area is taken as a valuable by- catch species in beam trawl fisheries targeting flatfish (sole and plaice), and to a lesser extent in the otter trawl and fixed net fisheries. Very little directed fishing activity occurs in this area. Effort for the main fleet with brill by-catches (beam trawls) in the North Sea and Skagerrak has declined by almost 50% between 2002 and 2012. Landings however have been relatively stable and above historical values since 1998 (this suggests that abundance of this species is increasing). Landings are considered a reliable approximation of catches as only little discarding of brill occurs. (ICES Advice, book 6, 2013) Dab (schar) Common dab (limanda limanda) is a widespread demersal species on the Northeast Atlantic shelf and distributed from the Bay of Biscay to Iceland and Norway; including the Barents Sea and the Baltic. There is no information on the stock identity of this species. Dab is one of the most abundant demersal species in the North Sea with the centre of its distribution in the southern North Sea. Dab in the North Sea and Skagerrak is a by-catch in the fishery for sole, plaice, shrimp and other demersal species, mainly in beam trawl fisheries. The effort of the beam trawl fleet in the North Sea and Skagerrak has declined by almost 50% between 2002 and 2012. Dab catches are generally discarded based on the availability of target species, and market price. After peaking around the turn of the century dab landings show gradual decline. Landing data are not complete and are not indicative for catches since discard rates are high. (ICES Advice, book 6, 2013) 4 Lemon sole (tongschar) There is little information available on the stock identity of lemon sole (Microstomus kitt), although tagging information suggests that the English Channel stock can be considered a separate stock (Jennings et al. 1993). Lemon sole in ICES Subarea IV, IIIa and VIId is mainly a by-catch species and is generally caught in mixed fisheries using otter trawls (~75%) and beam trawls (~25%). Some targeted activity takes place using otter trawls in the spring and summer (Seafish, 2014). The effort of the main fleet with lemon sole by-catches (otter trawls) in the North Sea and Skagerrak has declined by 14% (TR1) and 45% (TR2) between 2004 and 2012. Total landings data show a declining long-term trend. Discards are known to take place but data are insufficient to estimate discards. (ICES Advice, book 6, 2013) Turbot (tarbot) Turbot (Scophthalmus maximus) occurring the North Sea, the southern coast of Iceland, the western coast of Scotland and Ireland, and the Celtic Sea, including the Western Approaches, belong to one separate, northern Atlantic stock. Turbot is an economically valuable by-catch species. In ICES Subarea IV, turbot is mainly caught by mid-class and large beam trawlers. These vessels mostly target
Recommended publications
  • Age, Growth and Population Dynamics of Lemon Sole Microstomus Kitt(Walbaum 1792)

    Age, Growth and Population Dynamics of Lemon Sole Microstomus Kitt(Walbaum 1792)

    Age, growth and population dynamics of lemon sole Microstomus kitt (Walbaum 1792) sampled off the west coast of Ireland By Joan F. Hannan Masters Thesis in Fish Biology Galway-Mayo Institute of Technology Supervisors of Research Dr. Pauline King and Dr. David McGrath Submitted to the Higher Education and Training Awards Council July 2002 Age, growth and population dynamics of lemon sole Microstomus kitt (Walbaum 1792) sampled off the west coast of Ireland Joan F. Hannan ABSTRACT The age, growth, maturity and population dynamics o f lemon sole (Microstomus kitt), captured off the west coast o f Ireland (ICES division Vllb), were determined for the period November 2000 to February 2002. The maximum age recorded was 14 years. Males o f the population were dominated by 4 year olds, while females were dominated by 5 year olds. Females dominated the sex ratio in the overall sample, each month sampled, at each age and from 22cm in total length onwards (when N > 20). Possible reasons for the dominance o f females in the sex ratio are discussed. Three models were used to obtain the parameters o f the von Bertalanfly growth equation. These were the Ford-Walford plot (Beverton and Holt 1957), the Gulland and Holt plot (1959) and the Rafail (1973) method. Results o f the fitted von Bertalanffy growth curves showed that female lemon sole o ff the west coast o f Ireland grew faster than males and attained a greater size. Male and female lemon sole mature from 2 years o f age onwards. There is evidence in the population o f a smaller asymptotic length (L«, = 34.47cm), faster growth rate (K = 0.1955) and younger age at first maturity, all o f which are indicative o f a decrease in population size, when present results are compared to data collected in the same area 22 years earlier.
  • Collapse and Recovery of Marine Fishes

    Collapse and Recovery of Marine Fishes

    letters to nature sulphide complexes, indicating that Cu sulphide clusters are more 7. Al-Farawati, R. & van den Berg, C. M. G. Metal-sulfide complexation in seawater. Mar. Chem. 63, 331–352 (1999). stable than Cu organic complexes. This explains why laboratory 8. Luther III, G. W., Rickard, D. T., Theberge, S. M. & Olroyd, A. Determination of metal (bi)sulfide cultures of oceanic phytoplankton have been observed to increase stability constants of Mn2+,Fe2+,Co2+,Ni2+,Cu2+, and Zn2+ by voltammetric methods. Environ. Sci. the production of total dissolved sulphides when the concentrations Technol. 30, 671–679 (1996). of free Cu and Zn in the culture media were increased22. Although 9. Helz, G. R, Charnock, J. M., Vaughan, D. J. & Garner, C. D. Multinuclearity of aqueous copper and zinc bisulfide complexes—an EXAFS investigation. Geochim. Cosmochim. Acta 57, the data that we report here suggest that metal sulphide formation is 15–25 (1993). a means of detoxifying trace metals for organisms, further toxico- 10. Luther III, G. W., Theberge, S. M. & Rickard, D. T. Evidence for aqueous clusters as intermediates logical studies are needed to quantify the roles both sulphides and during zinc sulfide formation. Geochim. Cosmochim. Acta 19/20, 3159–3169 (1999). ‘natural’ organic ligands play in controlling Cu toxicity in natural 11. Peters, J. W., Lanzilotta, W. N., Lemon, B. J. & Seefeldt, L. C. X-ray crystal structure of the Fe-only hydrogenase (Cpl) from Clostridium pasteurianum to 1.8 angstrom resolution. Science 282, 1853– waters. 1858 (1998). Sulphur complexation may have a dramatic effect on the acute 12.
  • Appendix 13.2 Marine Ecology and Biodiversity Baseline Conditions

    Appendix 13.2 Marine Ecology and Biodiversity Baseline Conditions

    THE LONDON RESORT PRELIMINARY ENVIRONMENTAL INFORMATION REPORT Appendix 13.2 Marine Ecology and Biodiversity Baseline Conditions WATER QUALITY 13.2.1. The principal water quality data sources that have been used to inform this study are: • Environment Agency (EA) WFD classification status and reporting (e.g. EA 2015); and • EA long-term water quality monitoring data for the tidal Thames. Environment Agency WFD Classification Status 13.2.2. The tidal River Thames is divided into three transitional water bodies as part of the Thames River Basin Management Plan (EA 2015) (Thames Upper [ID GB530603911403], Thames Middle [ID GB53060391140] and Thames Lower [ID GB530603911401]. Each of these waterbodies are classified as heavily modified waterbodies (HMWBs). The most recent EA assessment carried out in 2016, confirms that all three of these water bodies are classified as being at Moderate ecological potential (EA 2018). 13.2.3. The Thames Estuary at the London Resort Project Site is located within the Thames Middle Transitional water body, which is a heavily modified water body on account of the following designated uses (Cycle 2 2015-2021): • Coastal protection; • Flood protection; and • Navigation. 13.2.4. The downstream extent of the Thames Middle transitional water body is located approximately 12 km downstream of the Kent Project Site and 8 km downstream of the Essex Project Site near Lower Hope Point. Downstream of this location is the Thames Lower water body which extends to the outer Thames Estuary. 13.2.5. A summary of the current Thames Middle water body WFD status is presented in Table A13.2.1, together with those supporting elements that do not currently meet at least Good status and their associated objectives.
  • Hyperpigmentation in North Sea Dab Limanda Limanda. I. Spatial and Temporal Patterns and Host Effects

    Hyperpigmentation in North Sea Dab Limanda Limanda. I. Spatial and Temporal Patterns and Host Effects

    Vol. 103: 9–24, 2013 DISEASES OF AQUATIC ORGANISMS Published March 13 doi: 10.3354/dao02554 Dis Aquat Org OPENPEN ACCESSCCESS Hyperpigmentation in North Sea dab Limanda limanda. I. Spatial and temporal patterns and host effects F. Grütjen1, T. Lang2,*, S. Feist3, D. Bruno4, P. Noguera4, W. Wosniok5 1Department of Biological Sciences, Zoology, University of Rostock, 18055 Rostock, Germany 2Thünen Institute of Fisheries Ecology, 27472 Cuxhaven, Germany 3Centre for the Environment, Fisheries and Aquaculture Science, Weymouth, Dorset DT4 8UB, UK 4Marine Scotland Science, Aberdeen AB11 9DB, UK 5Institute of Statistics, University of Bremen, 28334 Bremen, Germany ABSTRACT: Hyperpigmentation is a term describing a specific pigment anomaly affecting com- mon dab Limanda limanda in the North Sea and, less frequently, in adjacent areas, e.g. the Eng- lish Channel, Irish and Celtic Seas, western Baltic Sea and Icelandic waters. Other North Sea flat- fish species are also affected, but at a markedly lower prevalence. The condition is characterised by the occurrence of varying degrees of green to black patchy pigment spots in the skin of the upper (ocular) body side and pearly-white pigment spots in the skin of the lower (abocular) body side. In the course of fish disease monitoring programmes carried out by Germany and the UK (England and Scotland), a pronounced spatial pattern of hyperpigmentation has been detected in the North Sea. An increase in prevalence has been recorded in almost all North Sea areas studied in the past 2 decades. The prevalence recorded in hot spot areas of the condition increased from 5 to >40% between 1988 and 2009.
  • Mellergaard3

    Mellergaard3

    Downloaded from orbit.dtu.dk on: Oct 01, 2021 Epidemiology of X-cell gill disease in common dab Limanda limanda Mellergaard, Stig; Nielsen, Else Published in: Diseases of Aquatic Organisms Link to article, DOI: 10.3354/dao025107 Publication date: 1996 Document Version Publisher's PDF, also known as Version of record Link back to DTU Orbit Citation (APA): Mellergaard, S., & Nielsen, E. (1996). Epidemiology of X-cell gill disease in common dab Limanda limanda. Diseases of Aquatic Organisms, 25(1-2), 107-116. https://doi.org/10.3354/dao025107 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. DISEASES OF AQUATIC ORGANISMS Vol. 25: 107-116, 1996 Published May 9 Dis Aquat Org Epidemiology of X-cell gill disease in common dab Limanda limanda Stig ~ellergaard'~*,Else ~ielsen~ 'Danish Institute for Fisheries Research, Department for Marine and Coastal Zone Ecology, Fish Disease Laboratory, Biilowsvej 13, DK-1870 Frederiksberg C, Denmark 'Danish Institute for Fisheries Research, Department for Marine and Coastal Zone Ecology, Charlottenlund Castle, DK-2920 Charlottenlund.
  • Liver Histopathology in Baltic Flounder

    Liver Histopathology in Baltic Flounder

    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Electronic Publication Information Center Marine Pollution Bulletin 53 (2006) 488–496 www.elsevier.com/locate/marpolbul Liver histopathology in Baltic flounder (Platichthys flesus)as indicator of biological effects of contaminants Thomas Lang a,*, Werner Wosniok b, Janina Barsˇiene_ c, Katja Broeg d, Justyna Kopecka e, Jari Parkkonen f a Federal Research Centre for Fisheries, Institute of Fishery Ecology, Deichstrasse 12, 27472 Cuxhaven, Germany b University of Bremen, Institute of Statistics, Bibliothekstrasse 1, 28334 Bremen, Germany c Institute of Ecology of Vilnius University, Akademijos 2, 08412 Vilnius, Lithuania d Alfred Wegener Institute for Polar and Marine Research, Am Handelsshafen 12, 27570 Bremerhaven, Germany e Institute of Oceanology, Powstancow Warszawy 55, P.O. Box 197, 81-712 Sopot, Poland f Gothenburg University, Box 463, 40530 Gothenburg, Sweden Abstract Results are presented of a study on liver histopathology in Baltic flounder (Platichthys flesus) carried out in 2001 and 2002 in four coastal sampling areas of the Baltic Sea: Kva¨do¨fja¨rden (Swedish east coast, reference area), Klaipeda-Butinge (Lithuanian coast), Gulf of Gdansk (Polish coast), and Wismar Bay (German coast) within the framework of the EU-funded BEEP project. Liver lesions were diagnosed and categorised using standardised methodologies and, for a spatial and temporal assessment of the prevalence and types of lesions detected, a scoring system was applied, involving the calculation of mean histopathology lesion scores. 83.0% of the 436 female flounder examined (size range: 20–43 cm total length, age range: 2–8 years) were affected by liver lesions, out of which 74.3% were assigned to the category of non-specific, 3.4% to the category of early toxicopathic non-neoplastic, 4.6% to the category of pre-neoplastic and 0.7% to the category of neoplastic lesions.
  • 6 North Sea 6.1 Ecosystem Overview 6.1.1 Ecosystem Components

    6 North Sea 6.1 Ecosystem Overview 6.1.1 Ecosystem Components

    6 North Sea 6.1 Ecosystem overview 6.1.1 Ecosystem components Seabed topography and substrates The topography of the North Sea can be broadly described as having a shallow (<50 m) southeastern part, which is sharply separated by the Dogger Bank from a much deeper (50–100 m) central part that runs north along the British coast. The central northern part of the shelf gradually slopes down to 200 m before reaching the shelf edge. Another main feature is the Norwegian Trench running east along the Norwegian coast into the Skagerrak with depths up to 500 m. Further to the east, the Norwegian Trench ends abruptly, and the Kattegat is of depths similar to the main part of the North Sea (Figure 6.1.1). The substrates are dominated by sands in the southern and coastal regions and fine muds in deeper and more central parts (Figure 6.1.2). Sands become generally coarser to the east and west, with patches of gravel and stones existing as well. In the shallow southern part, concentrations of boulders may be found locally, originating from transport by glaciers during the ice ages. This specific hard-bottom habitat has become scarcer, because boulders caught in beam trawls are often brought ashore. The area around, and to the west of the Orkney/Shetland archipelago is dominated by coarse sand and gravel. The deep areas of the Norwegian Trench are covered with extensive layers of fine muds, while some of the slopes have rocky bottoms. Several underwater canyons extend further towards the coasts of Norway and Sweden.
  • Fish and Fish Populations

    Fish and Fish Populations

    Intended for Energinet Document type Report Date March 2021 THOR OWF TECHNICAL REPORT – FISH AND FISH POPULATIONS THOR OWF TECHNICAL REPORT – FISH AND FISH POPULATIONS Project name Thor OWF environmental investigations Ramboll Project no. 1100040575 Hannemanns Allé 53 Recipient Margot Møller Nielsen, Signe Dons (Energinet) DK-2300 Copenhagen S Document no 1100040575-1246582228-4 Denmark Version 5.0 (final) T +45 5161 1000 Date 05/03/2021 F +45 5161 1001 Prepared by Louise Dahl Kristensen, Sanne Kjellerup, Danni J. Jensen, Morten Warnick https://ramboll.com Stæhr Checked by Anna Schriver Approved by Lea Bjerre Schmidt Description Technical report on fish and fish populations. Rambøll Danmark A/S DK reg.no. 35128417 Member of FRI Ramboll - THOR oWF TABLE OF CONTENTS 1. Summary 4 2. Introduction 6 2.1 Background 6 3. Project Plan 7 3.1 Turbines 8 3.2 Foundations 8 3.3 Export cables 8 4. Methods And Materials 9 4.1 Geophysical survey 9 4.1.1 Depth 10 4.1.2 Seabed sediment type characterization 10 4.2 Fish survey 11 4.2.1 Sampling method 12 4.2.2 Analysis of catches 13 5. Baseline Situation 15 5.1 Description of gross area of Thor OWF 15 5.1.1 Water depth 15 5.1.2 Seabed sediment 17 5.1.3 Protected species and marine habitat types 17 5.2 Key species 19 5.2.1 Cod (Gadus morhua L.) 20 5.2.2 European plaice (Pleuronectes platessa L.) 20 5.2.3 Sole (Solea solea L.) 21 5.2.4 Turbot (Psetta maxima L.) 21 5.2.5 Dab (Limanda limanda) 22 5.2.6 Solenette (Buglossidium luteum) 22 5.2.7 Herring (Clupea harengus) 22 5.2.8 Sand goby (Pomatoschistus minutus) 22 5.2.9 Sprat (Sprattus sprattus L.) 23 5.2.10 Sandeel (Ammodytes marinus R.
  • Fish Bulletin 161. California Marine Fish Landings for 1972 and Designated Common Names of Certain Marine Organisms of California

    Fish Bulletin 161. California Marine Fish Landings for 1972 and Designated Common Names of Certain Marine Organisms of California

    UC San Diego Fish Bulletin Title Fish Bulletin 161. California Marine Fish Landings For 1972 and Designated Common Names of Certain Marine Organisms of California Permalink https://escholarship.org/uc/item/93g734v0 Authors Pinkas, Leo Gates, Doyle E Frey, Herbert W Publication Date 1974 eScholarship.org Powered by the California Digital Library University of California STATE OF CALIFORNIA THE RESOURCES AGENCY OF CALIFORNIA DEPARTMENT OF FISH AND GAME FISH BULLETIN 161 California Marine Fish Landings For 1972 and Designated Common Names of Certain Marine Organisms of California By Leo Pinkas Marine Resources Region and By Doyle E. Gates and Herbert W. Frey > Marine Resources Region 1974 1 Figure 1. Geographical areas used to summarize California Fisheries statistics. 2 3 1. CALIFORNIA MARINE FISH LANDINGS FOR 1972 LEO PINKAS Marine Resources Region 1.1. INTRODUCTION The protection, propagation, and wise utilization of California's living marine resources (established as common property by statute, Section 1600, Fish and Game Code) is dependent upon the welding of biological, environment- al, economic, and sociological factors. Fundamental to each of these factors, as well as the entire management pro- cess, are harvest records. The California Department of Fish and Game began gathering commercial fisheries land- ing data in 1916. Commercial fish catches were first published in 1929 for the years 1926 and 1927. This report, the 32nd in the landing series, is for the calendar year 1972. It summarizes commercial fishing activities in marine as well as fresh waters and includes the catches of the sportfishing partyboat fleet. Preliminary landing data are published annually in the circular series which also enumerates certain fishery products produced from the catch.
  • Full Text in Pdf Format

    Full Text in Pdf Format

    DISEASES OF AQUATIC ORGANISMS Vol. 2: 197-204, 1987 Published July 30 Dis. aquat. Org. I Gill X-celllesions of dab Limanda limanda in the North Sea ' Marine Laboratory, Victoria Road. Aberdeen. Scotland MAFF Fish Diseases Laboratory, The Nothe. Weymouth. England Zoologisches Institut und Zoologisches Museum der Universitat Hamburg, Martin-Luther-King-Platz 3, D-2000 Hamburg 13, Federal Republic of Germany Bundesforschungsanstalt fiir Fischerei, Institut fiir Kiisten- und Bimenfischerei. Toxikologisches Laboratorium, Niedersachsenstr. 219, D-2190 Cuxhaven, Federal Republic of Germany ABSTRACT: Up to 5% of dab Lunanda limanda L, in catches of a research vessel on the Dogger Bank (North Sea) had gills showing the pathological changes of marked swelling and pale colouration. The condition in catches in other parts of the southern North Sea showed a lower prevalence. A light and electron microscope examination showed the lesions to be due to an intra-epidermal accumulation of x- cells. The structure of these cells was atypical of normal dab cells so an infectious aetiology may be indicated. There was evidence of cell motility in peripheral parts of lesions. Variability in structure of x- cells was considered to be mainly associated with degenerative changes, particularly with cells in the centre of lesions. Envelope cells whlch characteristically encapsulated individual X-cells had features suggesting an epithelia1 origin. A cellular reaction involving macrophages containing X-cell remnants in phagocytic vacuoles was typical of areas of extensive X-cell degeneration. INTRODUCTION MATERIALS AND METHODS Recent investigations into diseases of fish in the Positions sampled were in the North Sea south of North Sea have revealed that dab Limanda limanda L.
  • Recycled Fish Sculpture (.PDF)

    Recycled Fish Sculpture (.PDF)

    Recycled Fish Sculpture Name:__________ Fish: are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. At 32,000 species, fish exhibit greater species diversity than any other group of vertebrates. Sculpture: is three-dimensional artwork created by shaping or combining hard materials—typically stone such as marble—or metal, glass, or wood. Softer ("plastic") materials can also be used, such as clay, textiles, plastics, polymers and softer metals. They may be assembled such as by welding or gluing or by firing, molded or cast. Researched Photo Source: Alaskan Rainbow STEP ONE: CHOOSE one fish from the attached Fish Names list. Trout STEP TWO: RESEARCH on-line and complete the attached K/U Fish Research Sheet. STEP THREE: DRAW 3 conceptual sketches with colour pencil crayons of possible visual images that represent your researched fish. STEP FOUR: Once your fish designs are approved by the teacher, DRAW a representational outline of your fish on the 18 x24 and then add VALUE and COLOUR . CONSIDER: Individual shapes and forms for the various parts you will cut out of recycled pop aluminum cans (such as individual scales, gills, fins etc.) STEP FIVE: CUT OUT using scissors the various individual sections of your chosen fish from recycled pop aluminum cans. OVERLAY them on top of your 18 x 24 Representational Outline 18 x 24 Drawing representational drawing to judge the shape and size of each piece. STEP SIX: Once you have cut out all your shapes and forms, GLUE the various pieces together with a glue gun.
  • WINTER FLOUNDER / Pseudopleuronectes Americanus (Walbaum 1792) / Blackback, Georges Bank Flounder, Lemon Sole, Rough Flounder / Bigelow and Schroeder 1953:276-283

    WINTER FLOUNDER / Pseudopleuronectes Americanus (Walbaum 1792) / Blackback, Georges Bank Flounder, Lemon Sole, Rough Flounder / Bigelow and Schroeder 1953:276-283

    WINTER FLOUNDER / Pseudopleuronectes americanus (Walbaum 1792) / Blackback, Georges Bank Flounder, Lemon Sole, Rough Flounder / Bigelow and Schroeder 1953:276-283 Description. Body oval, about two and a quarter times as long to base of caudal fin as it is wide, thick-bodied, and with a proportionately broader caudal peduncle and tail than any of the other local small flatfishes (Fig. 305). Mouth small, not gaping back to eye, lips thick and fleshy. Blind side of each jaw armed with one series of close-set incisor-like teeth. Eyed side with only a few teeth, or even toothless. Dorsal fin originates opposite forward edge of upper eye, of nearly equal height throughout its length. Anal fin highest about midway, preceded by a short, sharp spine (postabdominal bone). Pelvic fins alike on both sides of body, separated from long anal fin by a considerable gap. Gill rakers short and conical. Lateral line nearly straight, with a slight bow above pectoral fin. Scales rough on eyed side, including interorbital space; smooth on blind side in juveniles and mature females, rough in mature males when rubbed Georges Bank fish of 63.5 cm, weighing 3.6 kg. The NEFSC from caudal peduncle toward head. An occasional large adult female groundfish bottom trawl survey collected two 64-cm females, one on may also be rough ventrally. 22 October 1986 at 42°67' N, 67°32' W and a second on 15 Apri11997 at 41°01' N, 68°25'W (R. Brown, pers. comm., 25 Sept. Meristics. Dorsal fin rays 59-76; anal fin rays 44-58; pectoral fin 1998).