The Bering

The Bering Sea is a subpolar sea bounded by the Bering Strait to the north and the Aleutian Islands archipelago to the south. Geographically, the Bering Sea lies between 52° N and 66° N, and 162° E and 157° W. The narrow (85-km long) and shallow (<42 m deep) passage of the Bering Strait connects the Bering Sea to the south with the Chukchi Sea and the Arctic Ocean in the north. The sea area covers almost 3 million km2 and is divided almost equally between a deep basin in the southwestern part and a large, extensive continental shelf in the eastern and northern parts. The eastern continental shelf is 1200 km in length, exceeds 500 km in width at its narrowest point, and is the widest continental shelf outside the Arctic Ocean. The shelf is characterized as a featureless plain that deepens gradually from its extensive shoreline to the shelf break at about 170 m depth. Very limited commercial fisheries are prosecuted in the Chukchi Sea or in the Arctic Ocean north of the Bering Strait due to known low resource abundance, operating difficulties, and distance from markets. Marine mammal populations are locally important for subsistence use.

The continental shelves of the eastern and western Bering Sea combine to produce one of the world's largest and most productive fishing areas. They also contain some of the largest populations of marine mammals, birds, crabs, and groundfish in the world. In all, 25% of the total global yield of fish came from the region in the 1970s.

Commercial fisheries in the Bering Sea are generally large-scale trawl fisheries for groundfish, of which about 30% of the total catch is processed at sea and the remainder is delivered to shoreside processing plants in Russia and the United States. The home base for many of the Bering Sea vessels is outside the Arctic region, reflecting the comparative advantage of supply and service available in lower cost regions. Small coastal communities have a strong complement of indigenous peoples with subsistence fishing interests. They depend on coastal species, especially salmon, herring, and halibut; however, the overlap with commercial activities is generally small. Anadromous species (marine species that spawn in fresh water) extend far inland via the complex river systems and are critical resources for native peoples.

Annual catches of all commercial groundfish species for the period 1990-2001 in the US eastern Bering Sea EEZ ranged from 1.3 to 1.8 million tons and averaged 1.6 million tons. The walleye pollock catch averaged 1.2 million tons and ranged from 0.99 to 1.45 million tons. In the western Bering Sea, the total groundfish catch reached 1.45 million tons in 1988, of which walleye pollock contributed 1.29 million tons. The annual catch for the period 1990-2001 averaged 0.73 million tons, ranging from 0.45 to 1.06 million tons. On average, walleye pollock comprised 89% of the catch over the 11-year period.

The Bering Sea is an important habitat for many stocks comprising the five species of Pacific salmon during the ocean phase of their life history. Here, the diverse stocks intermingle from origins in Siberia, Alaska, the Aleutian Islands, Japan, Canada, and the US west coast. The earliest fisheries for salmon were likely by native subsistence fisheries in which salmon were captured returning to their native streams to spawn. During the 20th century, there were three main fisheries for salmon in the Bering Sea: (1) the Russian and Alaskan domestic fisheries, (2) the Japanese high-seas gillnet and longline fishery, and (3) the bycatch of salmon in the groundfish fisheries.

Salmon canneries first appeared on the Alaskan side of the Bering Sea in the late 1890s to process fish returning to Bristol Bay. It is reported that between 1894 and 1917, the Kvichak and Nushagak rivers flowing into Bristol Bay produced 10 million sockeye salmon annually. Purse seines and gill nets were the primary fishing gear used in the early days of the fishery. Gill nets were hauled from the beach using horses, which were later replaced by engines, whereas the purse seine fishery started around the time of World War I with the advent of powered fishing craft. Purse seining continues to the present as the primary gear in a highly mobile fleet fishing nearshore, which assures the targeting of specific salmon stocks. Although all five species of Pacific salmon are present in Bristol Bay, sockeye salmon are by far the most abundant and have dominated the salmon catch for years. The Bristol Bay salmon catch for all species totaled 42 million fish in 1993, of which 41 million were sockeye salmon, the largest catch on record. On average, pink salmon contributed 73.8% of the Russian salmon catch in the western Bering Sea from 1952 to 1993, chum salmon—24.2%, sockeye salmon 1.3%, Chinook— 0.6%, and coho only 0.1%. Since 1989, the runs of pink salmon to the eastern Kamchatka coast have been in good condition during odd years. The historical high catch totaled 83,640 t in 1999. The average pink salmon catch (38,390 t) for 1989-2001 is more than twice the level for 1952-1993 (15,996 t). Similarly, chum salmon catches were also stable at 11,000-12,000 t in 2000-2001 compared to 5250 t for 1952-1993. The recent improved stock conditions coincide with new fishery regulations that limit the chum salmon bycatch during the pink salmon fishery. The main sockeye salmon fishery in eastern Kamchatka results from the productive Kamchatka River, slightly southward of the Bering Sea.

The Japanese high-seas gill-net and long-line salmon fishery expanded into the Bering Sea in 1952 with three motherships and 57 catcher boats, which grew to 14 motherships and 407 catcher boats by 1956. The peak catch of 116,200 t occurred in 1955 and ranged from

71,000 to 87,000 t for the 21-year period 1957-1977. Sockeye, chum, and, pink salmon comprised 95% of the catch in this fishery, which ceased operations in 1983. The floating gill nets were typically 50 m wide and were assembled in separate sets ranging from 6 to 9 nautical miles in length. Mesh sizes were 13 cm and the gear was set at twilight and retrieved after 1 a.m. The bycatch of salmon in the commercial groundfish fisheries is of less importance than the directed fisheries mentioned above, but still accounts for fishing mortality important to resource managers. Observer sampling of the groundfish fishery indicates that Chinook salmon are more frequent in the bottom trawl catch and the other salmon species are more frequent in the pelagic trawls. In the western Bering Sea, primarily Chinook and chum salmon were present in the bottom trawl catches during research surveys in 1974-1991.

Alf HAkon Hoel and Hjalmar Viljamsson

See also Barents Sea; Bering Sea; Capelin; Cod; Fish; Fish Farming; Greenland Halibut; Herring; Pollock; Salmon

Further Reading

Bakkala, R.G., Structure and Historical Changes in the Groundfish Complex of the Eastern Bering Sea, NOAA Tech. Rep. NMFS 114, 1993 Blindheim, J. & H.R. Skjoldal, "Effects of Climatic Changes on the Biomass Yield of the Barents Sea, Norwegian Sea, and West Greenland Large Marine ecosystems." In Large Marine Ecosystems: Stress, Mitigration and Sustainability, edited by K. Sherman, L.M. Alexander & B.D. Gold, Washington, District of Columbia: AAAS Pub. 92-395, 1992 National Research Council, The Bering Sea Ecosystem, Washington, District of Columbia: National Academy Press, 1996

Palsson, Gisli, Coastal Economies, Cultural Accounts: Human Ecology and Icelandic Discourse, Manchester: Manchester University Press, 2001 Rasmussen, Rasmus O. & Lawrence C. Hamilton, The Development of Fisheries in Greenland, Roskilde: North Atlantic Regional Studies, Roskilde University, 2001 Sakshaug, Egil & John Walsh, "Marine Biology: Biomass, Productivity Distributions and their Variability in the Barents and Bering Seas." In The Arctic: Environment, People and Policy, edited by Mark Nuttall & Terry V. Callaghan, Amsterdam: Harwood Academic Publishers, 2000, pp.163-196 Wespestad, V.G., "The status of Bering Sea pollock and the effect of the 'donut hole' fishery." Fisheries, 18 (1993): 18-24

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