Trophic Position of Pacific Salmon Juveniles in the Western Bering Sea Epipelagic Communities during Autumn

摘要

The major purpose of our study was the determination of the trophic structure of juvenile Pacific salmon in the epipelagic layer of the western Bering Sea during autumn. 2002-2004 data were collected on research vessels of TINRO-Centre. A total of 234 plankton and 255 trawl stations were made in the epipelagic zone (0-50 m), with stomachs from 11,078 fish taken for diet analyses. Standard methods, widely used in TINRO-Centre studies (Chuchukalo and Volkov 1986), were used for the analyses of fish stomach contents. We identified prey items, total prey weight and weight of each prey component from size categories of fish. Plankton was collected by Juday Net in the epipelagic layer (0-50 m) during day time and night time. All data were averaged for the regions: Commander Basin, western Aleutian Basin, Navarin regions, Karaginskyi, Olutorskyi and Anadyr Bays.