Study area for the northern fur seal tracking and walleye pollock abundance survey. a St. Paul Island is part of the Pribilof Islands (Alaska, USA) and home to the largest US colony of northern fur seals (C. ursinus). During the eastern Bering Sea groundfish survey, a single trawl is conducted in each 37.04 × 37.04 km grid (20 × 20 nm, gray boxes), with additional sampling at corner stations around St. Paul Island and St. Matthew Island (gray, open circles). Walleye pollock (G. chalcogrammus) abundance was measured at each grid station as number of fish (NUMCPUE) and weight of fish per unit effort (WTCPUE, filled gray circles). b Foraging trip tracks from northern fur seals instrumented during the 2006 reproductive season (July to October, n = 20). Only locations within the eastern Bering Sea groundfish survey grid (gray boxes and circles) were used for analysis.