The Atlantic cod, Gadus morhua, is a well-known demersal food fish belonging to the family Gadidae. It is also commercially known as cod, codling or haberdine.
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 Baltic Sea, the North Sea, areas around Iceland and the Barents Sea.
It can grow to 2 meters in length and weigh up to 96 kilograms (210 lb). It can live for 25 years and sexual maturity is generally attained between ages 2 to 4, but can be as late as 8 years in the northeast Arctic. Colouring is brown to green with spots on the dorsal side, shading to silver ventrally. A lateral line is clearly visible. Its habitat ranges from the shoreline down to the continental shelf.
The Northeast Atlantic is the world's largest population of cod. By far the largest part of this population is the North-East Arctic Cod, as it is labelled by the ICES, or the Arcto-Norwegian cod stock, also referred to as skrei, a Norwegian name meaning something like "the wanderer", distinguishing it from coastal cod. The North-East Arctic Cod is found in the Barents Sea area. This stock spawns in March and April along the Norwegian coast, about 40% around the Lofoten archipelago. Newly hatched larvae drift northwards with the coastal current while feeding on larval copepods. By summer the young cod reach the Barents Sea where they stay for the rest of their life, until their spawning migration. As the cod grow, they feed on krill and other small crustaceans and fish.
The spawning stock of North-East Arctic cod was more than a million tons following World War II, but declined to a historic minimum of 118,000 tons in 1987. The North-East Arctic cod catch reached a historic maximum of 1,343,000 tons in 1956, and bottomed out at 212,000 tons in 1990. Since 2000, the spawning stock has increased quite quickly, helped by low fishing pressure. However, there are worries about a decreased age at first spawning (often an early sign of stock collapse), combined with the level of discards and unreported catches. The total catch in 2003 was 521,949 tons, the major fishers being Norway (191,976 tons) and Russia (182,160 tons).