| The Midwater Assessment and Conservation Engineering (MACE) program of the Alaska
Fisheries Science Center (AFSC; NOAA National Marine Fisheries Service) conducted
an acoustic-trawl (AT) stock assessment survey in the eastern Bering Sea during the
summer of 2010 to estimate the distribution and abundance of walleye pollock (Gadus
chalcogrammus). The survey was conducted between 5 June and 7 August, 2010, along
the eastern Bering Sea (EBS) shelf and in the Cape Navarin area of Russia. The survey
was divided into three segments; leg 1 was 5 June to 24 June, leg 2 was 29 June to
16 July, and leg 3 was 20 July to 7 August, 2010. The survey was conducted onboard
NOAA Ship Oscar Dyson, a 64 meter stern trawler equipped with acoustic and oceanographic
instrumentation in addition to trawling and biological sampling capabilities. The
primary instrumentation for the survey was a Simrad EK60 split-beam echosounder system
utilizing five frequencies (18, 38, 70, 120, and 200 kHz) and a Simrad ME70 multibeam
echosounder, with the ME70 transmit pulse synchronized to the EK60 system. This data
set includes Kongsberg Simrad ME70 raw multibeam data, Seabird CTD data, and ship?s
navigation/oceanographic/meteorological sensor data. |