关键词：狭鳕；海洋设备；生物质能；数据分析
摘 要：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 (1.8DG 12.3DGC in 2010 vs. 0.7DG 8.3DGC in 2 0 and 0.9DG 8.9DGC 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. Matthew Island between the 100 m and 200 m isobaths. Estimated pollock abundance in midwater (between 16 m from the surface and 3 m off bottom) in the U.S. EEZ portion of the Bering Sea shelf was high compared to recent surveys. The 2010 pollock biomass estimate in the U.S. EEZ was 2.323 million metric tons (t). The 2009 biomass was 0.924 million t and the estimated 2008 biomass was 0.997 million t. East of 170DG W, the predominant length mode was 40 cm and most ages ranged between 3 and 6 years. In the U.S. west of 170DG W (87.4of total biomass), dominant modal lengths were 26, 16, and 39 cm, corresponding to pollock aged 2, 1, and 4, respectively. In Russia (5.3of total biomass), modal lengths and ages were generally similar to those in the U.S. west of 170DG W. Vertical distribution analyses indicated that 85of adult biomass was within 40 m of the seafloor. Juveniles were found both near the seafloor and higher in the water column; 65of juvenile biomass was within 40 m of the seafloor while 13was within 45 m of the surface. Finally, the first field tests of a non-extractive stereo camera-trawl system (Cam-Trawl) were successfully completed during the 2010 survey, and the multifrequency euphausiid backscatter index of abundance was successfully computed, indicating a reduced abundance of euphausiids compared with that in summer 2009.