NOAA Technical Memorandum
NMFS-AFSC-7
1990 bottom trawl survey of the eastern Bering Sea and continental shelf
Abstract
The Resource Assessment and Conservation Engineering Division of the Alaska Fisheries Science Center conducts annual bottom trawl surveys to monitor the condition of the demersal fish and crab stocks of the eastern Bering Sea continental shelf. The standard study area, surveyed each year since 1979, encompasses a major portion of the eastern Bering Sea shelf between the 20-m and the 200-m isobaths and from the Alaska Peninsula north to approximately the latitude of St. Matthew Island (lat. 60° 50' N) . In 1990, this area of 463,000 km2 was again surveyed by two chartered trawlers, the 30.5 m Alaska and the 33.5 m Ocean Hope 3.
Demersal populations were sampled by trawling for 30 minutes at stations centered in 20 × 20 nautical mile grids covering the survey area. At each station, species composition of the catch was determined and commercially important species were sampled to obtain length distributions and age structure samples.
Survey results presented in this report include relative fishing powers of the survey vessels, abundance estimates for fish and invertebrates, geographic distributions of economically important fish species and major fish families, size composition of principal fish species, and age and growth information for selected species. Surface and bottom temperatures recorded at each sampling station are also presented.
Appendices provide detailed station data and computer listings of the analyses of abundance and biological data of the sampled populations.
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