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The Atlantic cod (Gadus morhua) is a well-known foodfish belonging to the family Gadidae. It grows to two metres (6 1/2 feet) in length. Colouring is brown to green on the dorsal side, shading to silver ventrally. Its habitat ranges from the shoreline down to the continental shelf.
In the western Atlantic Ocean cod has a distribution north of Cape Hatteras, North Carolina, and round both coasts of Greenland; in the eastern Atlantic it is found from the Bay of Biscay north to the Arctic Ocean, including the North Sea, areas around Iceland and the Barents Sea, which is the most important feeding area.
Cod populations or stocks can differ significantly both in appearance and biology. For instance, the cod stocks of the Baltic Sea are adapted to low-salinity water. Organizations such as the Northwest Atlantic Fishery Organization (NAFO) and ICES divide the cod into management units or stocks; however these units are not always biologically distuigishable stocks. Some major stocks/management units on the Canadian/US shelf are (see map of NAFO areas) are the Southern Labrador-Eastern Newfoundland stock (NAFO divisions 2J3KL), the Northern Gulf of St. Lawrence stock (NAFO divisions 3Pn4RS), the Northern Scotian Shelf stock (NAFO divisions 4VsW), which all lie in Canadian waters, and the Georges Bank and Gulf of Maine stocks in USA waters. In the European Atlantic, there are separate stocks on the shelves of Iceland, the Faeroes, and Western Scotland, in the North Sea, Irish Sea and Celtic Sea, and two stocks in the Baltic Sea (the western and the eastern stock).
North-East Atlantic Cod
The North-East Arctic stock (also known as the Arcto-Norwegian stock), is at present the world's largest stock of Atlantic cod. It is also recognised as skrei (a Norwegian name meaning something like "the wanderer", distinguishing it from the non-migrating coastal cod). This stock spawn in March-April on the Norwegian coast, traditionally in the region of Lofoten, but also both further north and south. Newly hatched larvae drift northwards with the coastal current while feeding on larval copepods. In the summer, they have reached the Barents Sea, where they stay for the rest of their life except for their spawning migrations towards Lofoten. As they grow, they turn to krill and other crustaceans, and then to small fish. Adult cod feed mainly on fish such as capelin and herring. The North-East Arctic Cod also shows cannibalistic behaviour, especially when there is little capelin available. The spawning stock was more than 1,000,000 tons just after World War II but then declined to a historic mimimum of just 118,000 tons in 1987. The catch reached an historic maximum in 1956 (1,343,000 tons) and a minimum in 1990 (212,000 tons). Since 2000, the spawning stock has increased quite fast (both due to a low fishing pressure). However, there are worries about a decreased age at first spawning (often an early sign of stock collapse) and the level of discards and unreported catches. The total catch in 2003 it was 521,949 tons, Norway (191,976 tons) and Russia (182,160 tons) being the major exploiters (Source: ICES).
Catch of Atlantic Cod 1950-2002 North-East Atlantic (blue), North-West Atlantic (green) and Total (red). Source: FAO Fishstat 2004.
The North Sea cod stock is subject to an important cod fishery, mainly performed by European Union states (in 1999: Denmark: 31%; Scotland: 25%; the UK (England, Wales and Northern Ireland): 12%; the Netherlands: 10%; Belgium, Germany and Norway: 17%). In the 1970s, the annual catch was 200-300 000 tonnes, but catch quotas has repeatedly been reduced in the 1980s and 1990s. In spite of this, the spawning stock biomass is estimated to have been well below the precautionary level since 1984 and is at present at an historically low level. In 2003, ICES stated the there is a high risk of stock collapse if current exploitation levels continues, and recommended a recovery plan which included a total moratorium on cod fishing in the North Sea in 2004. At the December 2003 meeting in Brussels, the EU Council of Ministers decided that the international Total Allowable Catch for North Sea cod should be 27,300 tonnes in 2004.
North-West Atlantic Cod
The North-West Atlantic Cod has been regarded as heavily overfished throughout its range, resulting in a crash in the fishery in the United States and Canada during the early nineties. The fishery has yet to recover, and may not recover at all because of a possibly stable change in the food web. The North-west Atlantic populations spawn in the winter and spring in the Cape Cod region in a location called Georges Bank.
- The Centre for Environment Fisheries and Aquaculture Science
- Skrei - the miraculous cod
- The history of the northen cod fishery in Canada
- ICES recommendation for the North Sea Cod stock (2003)
- ICES recommendation for the North East Arctic Cod stock (2004)
- Reports on the status of Canadian fishing stocks, including cod
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