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AFSC/RACE/MACE: Results of 2012 Acoustic-trawl survey of the Shumagin Islands and
Sanak Trough dy1201
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The survey?s primary objective was to collect acoustic data and trawl information
to estimate midwater abundance and distribution of walleye pollock (Gadus chalcogrammus)
in the Gulf of Alaska (GOA) Shumagins Region during late winter and early spring.
Acoustic data were collected using five split-beam transducers (18, 38, 70, 120, and
200 kHz) and Simrad ER60 scientific echo sounders. Midwater and near-bottom acoustic
backscatter was sampled using an Aleutian Wing 30/26 Trawl (AWT) and a poly Nor?eastern
bottom trawl (PNE) with roller gear. This long-running survey has consistently provided
data on the pollock population in the western GOA during winter and spring months.
Surveys were conducted 13-22 February (cruise DY2012-01) in Sanak Trough and in the
Shumagin Islands area (comprised of Shumagin Trough, Stepovak Bay, Renshaw Point,
Unga Strait, and West Nagai Strait), and 17-27 March to estimate the distribution
andabundance of walleye pollock (Theragra chalcogramma).
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