IMR/PINRO J O S I E N I 2 R T 2007 E R E S P O R T JOINT PINRO/IMR REPORT ON THE STATE OFTHE BARENTS SEA ECOSYSTEM IN 2006 WITH EXPECTED SITUATION AND CONSIDERATIONS FOR MANAGEMENT Institute of Marine Research - IMR Polar Research Institute of Marine Fisheries and Oceanography - PINRO This report should be cited as: Stiansen, J.E and A.A. Filin (editors) Joint PINRO/IMR report on the state of the Barents Sea ecosystem 2006, with expected situation and considerations for management. IMR/PINRO Joint Report Series No. 2/2007. ISSN 1502-8828. 209 pp. Contributing authors in alphabetical order: A. Aglen, N.A. Anisimova, B. Bogstad, S. Boitsov, P. Budgell, P. Dalpadado, A.V. Dolgov, K.V. Drevetnyak, K. Drinkwater, A.A. Filin, H. Gjøsæter, A.A. Grekov, D. Howell, Å. Høines, R. Ingvaldsen, V.A. Ivshin, E. Johannesen, L.L. Jørgensen, A.L. Karsakov, J. Klungsøyr, T. Knutsen, P.A. Liubin, L.J. Naustvoll, K. Nedreaas, I.E. Manushin, M. Mauritzen, S. Mehl, N.V. Muchina, M.A. Novikov, E. Olsen, E.L. Orlova, G. Ottersen, V.K. Ozhigin, A.P. Pedchenko, N.F. Plotitsina, M. Skogen, O.V. Smirnov, K.M. Sokolov, E.K. Stenevik, J.E. Stiansen, J. Sundet, O.V. Titov, S. Tjelmeland, V.B. Zabavnikov, S.V. Ziryanov, N. Øien, B. Ådlandsvik, S. Aanes, A. Yu. Zhilin Joint PINRO/IMR report on the state of the Barents Sea ecosystem in 2006, with expected situation and considerations for management ISSUE NO.2 Figure 1.1. Illustration of the rich marine life and interactions in the Barents Sea. Editors: J.E. Stiansen1 and A.A. Filin2 Co-authors (in alphabetic order): A. Aglen1, N.A. Anisimova2, B. Bogstad1, S. Boitsov1, P. Budgell1, P. Dalpadado1, A.V. Dolgov2, K.V. Drevetnyak2, K. Drinkwater1, H. Gjøsæter1, A. A. Grekov2, D. Howell1, Å. Høines1, R. Ingvaldsen1, V.A. Ivshin2, E. Johannesen1, L.L. Jørgensen1, A.L. Karsakov2, J. Klungsøyr1, T. Knutsen1, P.A. Liubin2, L.J. Naustvoll1, K. Nedreaas1, I.E. Manushin2, M. Mauritzen1, S. Mehl1, N.V. Muchina2, M.A. Novikov2, E. Olsen1, E.L. Orlova2, G. Ottersen1, V.K. Ozhigin2, A.P. Pedchenko2, N.F. Plotitsina2, M. Skogen1, O.V. Smirnov2, K.M. Sokolov2, E.K. Stenevik1, J. Sundet1, O.V. Titov2, S. Tjelmeland1, V.B. Zabavnikov2, S.V. Ziryanov2, N. Øien1, B. Ådlandsvik1, S. Aanes1, A. Yu. Zhilin2 1 Institute of Marine Research (IMR), Norway 2 Polar Research Institute of Marine Fisheries and Oceanography (PINRO), Russia 1 Contents 1 Introduction ..................................................................................................... 5 2 General description of the ecosystem ..................................................... 7 2.1 Overview of the ecosystem ............................................................................ 7 2.2 Geographical description .............................................................................. 10 2.3 Climate ............................................................................................................. 11 2.3.1 Atmospheric conditions .................................................................................... 11 2.3.2 Hydrographical conditions ............................................................................... 15 2.3.3 Currents and transports ..................................................................................... 18 2.3.4 Ice conditions ................................................................................................... 20 2.4 Species communities .................................................................................... 20 2.4.1 Phytoplankton ................................................................................................... 20 2.4.2 Zooplankton ..................................................................................................... 21 2.4.3 Benthos ............................................................................................................. 23 2.4.4 Fish ................................................................................................................... 25 2.4.5 Marine Mammals ............................................................................................. 41 2.4.6 Seabirds ............................................................................................................ 45 2.5 Ecological relations ........................................................................................ 46 2.5.1 Marine Ecosystem Responses to Climate Variability ...................................... 46 2.5.2 Plankton and fish .............................................................................................. 47 2.5.3 Benthos and fish ............................................................................................... 49 2.5.4 Predation by fish ............................................................................................... 50 2.5.5 Predation by mammals ..................................................................................... 53 3 Impacts of the fisheries on the ecosystem ........................................... 58 3.1 General description of the fisheries and mixed fisheries ......................... 58 3.2 Mixed fisheries ................................................................................................ 60 3.3 Impact and by-catches of non-target species ............................................ 67 4 Monitoring of the ecosystem .................................................................... 69 4.1 Standard sections .......................................................................................... 69 4.1.1 Fugløya-Bear Island section ............................................................................. 70 4.1.2 North cape-Bear Island section ........................................................................ 70 4.1.3 Bear Island – East section ................................................................................ 70 4.1.4 Vardø-North section ......................................................................................... 71 4.1.5 Kola section ...................................................................................................... 71 4.1.6 Kanin section .................................................................................................... 71 4.1.7 Sem Island ........................................................................................................ 71 4.2 Fixed stations .................................................................................................. 71 4.3 Area coverage ................................................................................................ 71 4.3.1 Norwegian/Russian winter survey ................................................................... 73 4.3.2 Lofoten survey .................................................................................................. 73 4.3.3 Norwegian coastal survey ................................................................................ 73 4.3.4 Joint ecosystem autumn survey ........................................................................ 74 4.3.5 Russian Autumn-winter trawl-acoustic survey ................................................ 74 4.3.6 Survey on estimation of abundance of young herring in the Barents Sea ........ 74 4.3.7 Norwegian Greenland halibut survey ............................................................... 74 4.4 Numerical models .......................................................................................... 74 4.5 Other information sources ............................................................................ 75 4.6 Monitoring divided by ecosystem components ......................................... 75 2 5 Current and expected situation of the ecosystem .............................. 78 5.1 Overview .......................................................................................................... 78 5.1.1 Climate ............................................................................................................. 78 5.1.2 Phytoplankton and Zooplankton ...................................................................... 78 5.1.3 Benthos ............................................................................................................. 78 5.1.4 Fish ................................................................................................................... 79 5.1.5 Mammals and seabirds ..................................................................................... 79 5.2 Climate ............................................................................................................. 80 5.2.1 Atmospheric conditions .................................................................................... 80 5.2.2 Hydrographic conditions .................................................................................. 84 5.2.3 Currents and transports ..................................................................................... 91 5.2.4 Ice conditions ................................................................................................... 92 5.2.5 Expected situation ............................................................................................ 93 5.3 Phytoplankton ................................................................................................. 94 5.3.1 Current situation ............................................................................................... 94 5.3.2 Expected situation ...........................................................................................