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.

Eastern Bering Sea shelf walleye pollock (Theragra chalcogramma) abundance and distribution in midwater were assessed between 5 June and 7 August 2010 using acoustic-trawl techniques aboard the NOAA ship Oscar Dyson. The survey also assessed walleye pollock in the Cape Navarin area of Russia. Results showed that ocean surface temperatures were warmer in 2010 than in recent years (1.8° – 12.3°C in 2010 vs. 0.7° – 8.3°C in 2008 and 0.9° – 8.9°C in 2009). The majority of the pollock biomass in the U.S. Exclusive Economic Zone (EEZ) was located to the south and west of St.

Eastern Bering Sea shelf walleye pollock (Theragra chalcogramma) abundance and distribution in midwater were assessed between 2 June and 30 July 2007 using echo integration-trawl techniques aboard the NOAA ship Oscar Dyson. The survey also assessed walleye pollock in the Russian Cape Navarin area. In general, ocean conditions were cold in 2007, as in 2006. Surface waters averaged 5.0¿C in June and early July, but warmed to an average of 8.9¿C in mid- to late July.

Eastern Bering Sea shelf walleye pollock (Theragra chalcogramma) abundance and distribution in midwater were assessed between 9 June and 7 August 2009 using acoustic-trawl techniques aboard the NOAA ship Oscar Dyson. The survey also assessed walleye pollock in the Cape Navarin area of Russia. Results showed that ocean conditions were cold in 2009, as in the previous three years, compared to 2001-2005.

This data set describes the holding temperatures and developmental stages of larvae of red and blue king crab (Paralithodes camtschaticus and P. platypus) reared to the first crab stage at the Kodiak Laboratory.

Adult male and female northern fur seals (Callorhinus ursinus) are sexually segregated in different regions of the North Pacific Ocean and Bering Sea during their winter migration. Explanations for this involve interplay between physiology, predator-prey dynamics, and ecosystem characteristics, however possible mechanisms lack empirical support.

We conducted acoustic-trawl (AT) surveys of the Alaska northern Bering and Chukchi Seas during ice-free periods with a focus on Arctic cod (Boreogadus saida), a key species in Arctic ecosystems. The mixed species assemblages in the study area required a refinement of standard AT survey methods used in Alaska. These surveys indicate that midwater fishes are dominated by age-0 Arctic and saffron cod (Eleginus gracilis), capelin (Mallotus villosus), and Pacific herring (Clupea pallasii).

Alaska’s Bering Sea is home to some of the world’s most productive groundfish and crab stocks and the fisheries that depend on them. Their spatial overlap creates problems when bottom trawls affect crabs in their paths, either through capture and discard or damage to crabs that remain on the seafloor. We worked with Bering Sea bottom trawlers to develop and test changes to trawl footropes to minimize crab mortality, by reducing damage to crabs that are not caught, and maintaining low crab capture rates.

The Alaska pollock fishing industry, in collaboration with scientists at Alaska Pacific University, the Alaska Fisheries Science Center, and members of the fishing gear design and fabrication industry are actively pursuing new trawl designs to address bycatch and seabed contact issues while maintaining a viable pollock capture efficiency. Adult Alaska pollock (Theragra chalcogramma) aggregate on or near the seafloor, particularly during the day (e.g. Mecklenburg, et al. 2002, Tsuji, S. 1989).

The potential for unobserved mortality of crabs encountering bottom trawls, but not captured, has long been a concern in the management of Bering Sea fisheries. We evaluated how many such crabs die, including snow, Tanner and red king crabs, and demonstrated changes to trawl gear that substantially improved crab survival.