IMR/PINRO 1/2009 Survey Report from the Joint Norwegian-Russian
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IMR/PINRO J O S I E N 1 I T R 2009 E R E S P O R T SURVEY REPORT FROM THE JOINT NORWEGIAN/RUSSIAN ECOSYSTEM SURVEY IN THE BARENTS SEA AUGUST-OCTOBER 2008 Volume 1 Institute of Marine Research - IMR Polar Research Institute of Marine Fisheries and Oceanography - PINRO This report should be cited as: Anon. 2009. Survey report from the joint Norwegian/Russian ecosystem survey in the Barents Sea August-October 2008 volume 1. IMR/PINRO Joint Report Series, No. 1/2009. ISSN 1502-8828. 103 pp. SURVEY REPORT From the joint Norwegian/Russian ecosystem survey in the Barents sea August – October 2008 Volume 1 PREFACE The sixth joint ecosystem survey was carried out during the period 1 August to 4 October 2008. The survey encompasses various surveys that previously have been carried out jointly or at national basis. Joint investigations include the 0-group survey, the acoustic survey for pelagic fish (previously known as the capelin survey), and the investigations on young Greenland halibut north and east of Spitsbergen. Oceanographic investigations have always formed a part of these surveys, and studies on plankton have been included for many years. In recent years, observations of sea mammals, seabirds, bottom fishes and benthos have been included. Consequently, from 2003, these surveys were called “ecosystem surveys”. The present volume of the survey report covers many but not all aspects of the survey. The main focus is on the hydrographical conditions of the Barents Sea, the results from the 0- group investigations and from the acoustic investigation on pelagic fish (capelin, young herring, blue whiting and polar cod). Preliminary materials on sea mammals and seabird observations are also presented in Volume 1 of the report. Finalised analyses of results from investigations on plankton, bottom fish and benthos will only be made available as an electronic attachment to this report on the internet. The first version of the report was made in Tromsø 01 -03 October during a meeting between scientists participating in the survey. A list of the participating vessels with their respective scientific crews is given in Appendix I. Besides the participants on the vessels, the following specialists took part in the preparation of the survey report: From PINRO: K. Drevetnyak, Yu. Kovalev, E. Orlova, V. Nesterova, O. Yurko, P. Lubin, N. Anisimova From IMR: B. Bogstad, P. Dalpadado, E. Johannessen, T. Knutsen, K. Michalsen, C. Hvingel, J.E. Stiansen 4 Content PREFACE .............................................................................................................................................................. 4 Content ................................................................................................................................................................... 5 Synopsis .................................................................................................................................................................. 9 1 Methods ........................................................................................................................................ 11 1.1 Hydrography .................................................................................................................................. 11 1.2 0-group fish investigations ............................................................................................................ 11 1.3 Acoustic survey for pelagic fish .................................................................................................... 11 1.3.1 Area coverage ................................................................................................................................ 12 1.3.2 Computations of the stock sizes .................................................................................................... 12 1.4 Bottom trawl survey ...................................................................................................................... 12 1.4.1 Strata system used ......................................................................................................................... 12 1.5 Plankton investigations .................................................................................................................. 13 1.6 Stomach investigations .................................................................................................................. 14 1.7 Marine mammals and seabirds investigations ............................................................................... 14 1.8 Benthos observations ..................................................................................................................... 15 1.8.1 Purpose .......................................................................................................................................... 15 1.8.2 Criteria for selection of sampling locations ................................................................................... 15 1.8.3 Gears and methods ........................................................................................................................ 15 1.8.4 Bottom trawl .................................................................................................................................. 16 1.8.5 van Veen grab ................................................................................................................................ 16 1.8.6 Epibenthos trawls .......................................................................................................................... 16 1.9 Pollution ........................................................................................................................................ 17 2 Results and discussion ................................................................................................................. 19 2.1 Hydrographical conditions ............................................................................................................ 19 2.2 Distribution and abundance of 0-group fish .................................................................................. 21 2.2.1 Capelin .......................................................................................................................................... 21 2.2.2 Cod ................................................................................................................................................ 22 2.2.3 Haddock ........................................................................................................................................ 22 2.2.4 Herring .......................................................................................................................................... 23 2.2.5 Polar cod ........................................................................................................................................ 23 2.2.6 Saithe ............................................................................................................................................. 24 2.2.7 Redfish .......................................................................................................................................... 24 2.2.8 Greenland halibut .......................................................................................................................... 24 2.2.9 Long rough dab ............................................................................................................................. 25 2.2.10 Wolffish ......................................................................................................................................... 25 2.2.11 Sandeel .......................................................................................................................................... 25 2.2.12 Blue whiting .................................................................................................................................. 26 2.2.13 Gonatus (Gonatus fabricii) ............................................................................................................ 26 2.3 Distribution and abundance of pelagic fish ................................................................................... 26 2.3.1 Capelin .......................................................................................................................................... 26 2.3.2 Polar cod ........................................................................................................................................ 28 2.3.3 Herring .......................................................................................................................................... 29 2.3.4 Blue whiting .................................................................................................................................. 30 2.4 Demersal fish ................................................................................................................................. 31 2.4.1 Cod ................................................................................................................................................ 31 2.4.2 Haddock ........................................................................................................................................ 31 2.4.3 Saithe ............................................................................................................................................. 31 2.4.4