Population Structure of Blue King Crab (Paralithodes ...

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In the northwestern part of the Bering Sea, large aggregations of blue king crab, Paralithodes platypus, are known from the Gulf of Olyutorsk to the.
Pereladov, andWater D.M. Miljutin. 2002.Biology, PopulationManagement, Structure of Blue King Crabs inM.V. Cold Regions: andCrab Economics (Paralithodes platypus) in the Northwestern Bering Sea. In: A.J. Paul, E.G. Dawe, R. Elner, Alaska Sea G.H. Grant College Program • AK-SG-02-01, G.S. Jamieson, Kruse, R.S. Otto, B. Sainte-Marie, T.C. Shirley, and2002 D. Woodby (eds.), Crabs in Cold Water Regions: Biology, Management, and Economics. Alaska Sea Grant College Program, University of Alaska Fairbanks, pp. 511-520. doi:10.4027/ccwrbme.2002.37

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© Alaska Sea Grant, University of Alaska Fairbanks

Population Structure of Blue King Crab (Paralithodes platypus) in the Northwestern Bering Sea M.V. Pereladov and D.M. Miljutin Russian Federal Research Institute of Fisheries and Oceanography (VNIRO), Laboratory of Coastal Research, Moscow, Russia

Abstract In the northwestern part of the Bering Sea, large aggregations of blue king crab, Paralithodes platypus, are known from the Gulf of Olyutorsk to the Gulf of Anadyr. It is believed that these aggregations are portions of a single population. Maximum densities (12-21 individuals per trap) of commercial males were observed in winter at depths of 120-250 m during trapping and diving surveys in 1998-2000. Juveniles of both sexes (carapace width 21-49 mm) with densities of 7-12 individuals per m2 were found in Glubokaya Inlet at a depth of 15 m in summer. In summer, egg-bearing females were found along the coast at depths of 6-10 m, while mature females without eggs were caught at depths of 50-80 m. In winter, eggbearing females were caught at depths of 130-180 m, while females without eggs were not caught at all. We concluded that the Olyutorsk-Navarin population has three centers of reproduction: the Gulf of Anadyr, the area to the west of Cape Navarin, and the area of Natalia and Glubokaya inlets. The total abundance of commercial male blue king crabs from the Gulf of Olyutorsk to Cape Navarin was approximately 3 million individuals in 2000.

Introduction Blue king crab (Paralithodes platypus Brandt, 1850) is one of the most important commercial fishery resources in the Bering Sea. The species is distributed across a major part of the Bering Sea from the Gulf of Karagin in the west to the Gulf of Alaska in the east. In the Russian part of the Bering Sea, large aggregations of blue king crab are known from the Gulf of Olyutorsk to the Gulf of Anadyr. It is believed that these aggregations are portions of a single Olyutorsk-Navarin population. Several small local

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Pereladov and Miljutin — Blue King Crab

aggregations are also found in the Gulf of Karagin. The total annual catch of blue king crab in the Russian part of the Bering Sea during the last 10 years has fluctuated within a wide range of 800-2,500 tons and depends on climatic conditions and fishing effort. The main stocks of blue king crab are concentrated in the area between Cape Olyutorsk and Cape Navarin. The location of aggregations has been determined by trap surveys conducted over the past 10 years. A small quantity of noncommercial males (