The Arctic Fisheries Regions

The Barents Sea and the Northern Norwegian Sea

The Barents Sea is a shallow (150-250 m), Mediterranean semienclosed area: bordered to the north by the Svalbard and Franz Josef archipelagos, in the east by the large island of Novaya Zemlya, and in the south by the north coasts of Russia and Norway. The Barents Sea is open to the west, allowing the entrance of warm Atlantic water without which the whole area would be covered by Arctic waters. The Polar Front (the boundary between Atlantic and Arctic waters) is commonly found in the central and southeastern Barents Sea. The front may move quite far west in winter but retreats to the north and northeast in summer. The Atlantic influence is variable. A strong Atlantic influence driving the Polar Front far to the east and north is believed to enhance the survival of larval fish, while a small inflow of Atlantic water has the reverse effect. Through its size and generally high productivity at the lower links of the food chain, the Barents Sea is one of the most productive fishing grounds of the world.

For the past 1000 years, fishing for cod and herring has been important for coastal communities in northern Norway and Russia. Throughout the centuries, fishing was purely coastal and seasonal and based on the huge numbers of adult cod and herring migrating into nearshore waters for spawning during winterspring, as well as on the schools of adolescent cod feeding on spawning capelin along the northern coasts of Norway and Russia in April-June. Although offshore fishing began at the end of the 19th century, when cod were caught on the Svalbard banks and herring was fished with drift nets north of Iceland, the quantities caught in these fisheries were small compared to the coastal fisheries. Estimates of annual yields prior to 1900 indicate large fluctuations in the catches of both cod and herring. Otherwise, the dominant feature of these old catch series is the five- to ten fold increase between 1820 and 1880 as compared to yield levels of previous centuries. For fish species other than cod and herring, reliable estimates of yield prior to the 20th century are not available.

Total landings from the area cod, other demersal (bottom-dwelling fish), herring, as well as the Arctic species of capelin, polar cod, Greenland halibut, and northern shrimp increased from about 0.5 million tons at the beginning of the century to about 3 million tons in the 1970s. This increase has been related to a series of major technological improvements of fishing vessels and gear, as well as electronic instruments for fish finding and positioning.

The two most important fisheries in the Northeast Atlantic are still those of cod and herring. Prior to 1920, the bulk of the cod catch was from the large seasonal and coastal fisheries. In the 1920s and 1930s, an international bottom trawl fishery, targeting cod as well as other demersal (bottom dwelling) species like haddock and redfish and the semidemersal saithe, developed in offshore areas in the Barents Sea and off Svalbard. Annual catches increased from about 400,000 t in 1930 to 700—800,000 t at the end of the decade. Landings also remained high after World War II until the end of the 1970s, when catches declined sharply due to reduced stock size and the introduction of exclusive economic zones (EEZs) in 1977. Management measures have, at least periodically, been more effective since 1977, but fishing mortality of Barents Sea cod is still high, the spawning stock biomass well below the recommended precautionary level of 500,000 t, and recruitment to the stock has been low in recent years.

Herring, which spawn off the west coast of Norway in spring, grow to maturity at the age of 3-4 years in the southern Barents Sea, north Norwegian fjords and, in case of large year classes, even in the northeastern Norwegian Sea. Together with two much smaller stocks spawning in spring at the Faroes and Iceland and mixed with the Norwegian herring in the feeding season, this is potentially by far the largest herring complex in the world and was collectively called the Atlanto-Scandian herring. Until the mid-1960s, these herring would migrate to feed in summer north and east of Iceland, in the oceanic area between northeast Iceland and the island of Jan Mayen (c.71° N 8° W) as well as in the western Norwegian Sea. At this time, the overwintering area (October-December) was approximately 50-80 nautical miles east of Iceland, from where the spawning migration back across the Norwegian Sea to Norway, as well as to spawning grounds at Iceland and the Faroes, started in late December. In 1965 and subsequent years, there was a large cooling of the waters north and east of Iceland as well as of the northwestern and western Norwegian Sea. This was accompanied by a decimation of the stock of "redfeed" (calanoid copepods, mainly Calanus finmarchicus) in these areas. This, together with rapidly dwindling stock size caused by overfishing, completely disrupted the previous migration pattern of these herring.

Until the 1950s, Norwegian herring fisheries remained largely seasonal and nearshore. These fisheries were based on prespawning and spawning herring at or near the spawning grounds on the west coast as well as on the so-called small and fat juvenile and adolescent herring in the fjords of North Norway. The bulk of the landings came from Norwegian vessels. In the 1950s, Russian fishers developed a gillnet fishery in offshore waters in the Norwegian Sea, and in the late 1950s to early 1960s Norwegian, Icelandic, and Faroese purse seiners started using echo sounding equipment to locate herring and power blocks to haul the large seine nets. These technological developments resulted in a large increase of the total catch until 1966 (2 million tons). Thereafter, catches decreased rapidly and the stock collapsed. Effective management measures were neither advised nor implemented before the stock had collapsed completely. For a few subsequent years, a complete ban on fishing herring was enforced, followed by a period of a small experimental fishery for monitoring stock developments. For 25 years, stock abundance was low, the herring remained in Norwegian coastal waters throughout the year, and the stock was managed by Norway. During the 1990s, the stock recovered, started feeding migrations into the Norwegian Sea, and catch quotas and landings increased. In 2002, the total landings were 830,000 t.

A Norwegian fishery for capelin began in the 1950s and expanded rapidly in connection with the collapse of the herring in the 1960s. Russian vessels soon entered this fishery, and from 1965 and during the next 20 years Norwegian and Russian capelin catches were taken in autumn and winter and averaged approximately 2 million tons annually. In the mid-1980s, the stock crashed due to overfishing, but recovered in around four years. Since then, the Barents Sea capelin have twice declined drastically in abundance. The present-day capelin fishery in the Barents Sea is now pursued only in winter.

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