ME70 Water Column Sonar Data Collected During DY1002

Shelikof Strait Acoustic-Trawl Survey of Walleye Pollock (DY1002, ME70). 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 central Gulf of Alaska (GOA) and Shelikof Strait during late winter/early spring of 2010 to estimate the distribution and abundance of walleye pollock (Gadus chalcogrammus). The survey was conducted between 18 and 30 March, 2010, and included the central Gulf of Alaska along the shelf break east of Chirikof Island and throughout Shelikof Strait. The survey was conducted onboard NOAA Ship Oscar Dyson, a 64 meter stern trawler equipped with acoustic and oceanographic instrumentation in addition to 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/meterological sensor data.