The Role of Pacific Salmon in the Trophic Structure of the Upper Epipelagic Layer of the Western Bering Sea during Summer-Autumn 2002–2006

Pacific salmon are among the dominant fish in the epipelagic layer of the subarctic Pacific Ocean and are considered the principle consumers of forage resources. In recent years (1990s and 2000s) most Pacific salmon stocks have increased two-fold in abundance. Many researchers consider that such high abundance may increase interspecific competition for food and influence density-dependent factors during periods of limited food availability and may change salmon characteristics such as length, weight, fecundity, and the average age of populations. Long-term data series on Pacific salmon and their food resources have traditionally been collected during Russian surveys in the pelagic zone of the Far Eastern Seas and adjacent waters of the northwestern North Pacific Ocean. More recently (summer–autumn, 2002–2006) surveys have been conducted by TINRO-Centre in the epipelagic zone of the western Bering Sea as part of the international BASIS program. The integration of the results of these programs make it possible to better understand the status of Pacific salmon and their role in North Pacific pelagic communities. All correspondence should be addressed to S. Naydenko. e-mail: [email protected] The Role of Pacific Salmon in the Trophic Structure of the Upper Epipelagic Layer of the Western Bering Sea during Summer-Autumn 2002–2006 Svetlana V. Naydenko Pacific Scientific Research Fisheries Center (TINRO-Center), 4 Shevchenko Alley, Vladivostok 690600, Russia