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COD Gadus morrhua
In icelandic waters and in the Lofden islands, examples of up to 110 cm are often captured, weighing 15 Kg and of up to 20 years of age. Very rarely, examples can reach 150 cm and weigh 40 Kg. Theri habitat is along coastlines at depths of up to 600 metres, at temperatures of between 2 and 10 ºC; generally they stay close to the sea bed. Some of the larger fish, between 15 and 20 years old, venture further out to sea, in search of herring and other gregarious fish. The most important groups for industry are to be found in the Barent's Sea and around Iceland, Greenland and Terranova. The North Sea and the Baltic make up only 10% of the total cod population. Together with the large populations of emigrant cod, there are local species which live permanently close to the coastline or in the fiords. The cod mainly spawns in spring in waters at temperatures of between 4 and 6ºC. The number of eggs varies according to the size of the female between 500,000 and 5 million. The ova and sperm are released freely into the water while the male and female are closely in contact. The eggs are transparent and pelagic, measuring about 1.5 mm, and rise rapidly to the surface. The development of the embryo takes 2 to 4 weeks, depending on the water temperature. At birth, the young measure about 5 mm, after 3 to 5 months, having grown to between 3 and 6 cm, they move to the sea-bed. The cod is omnivorous, feeding on crabs, worms and molluscs and later on other fish species. The migratory cod follows the herring. uring the herring spawning season, cod are often captured with their stomachs full of eggs. The cod hardly feeds during the spawning season. The cod of Terranova, Greenland, Iceland and Norway do not mature until between 6 and 15 years, while those that inhabit coastal zones are able to reproduce at 2 years. The icelandic race spawns along the southeastern coastline and is similar to the arctic norwegian race. It has been demonstarted that they undertake long journeys reaching the Barents Sea and west Greenland. From 1920 onwards cod has been present in Greenland waters, due to the warming of the arctic ocean. Numbers captured in the Davis Straits have steadily increased, while captures outside nordic seas reduce. Regulations in the North Sea limit the minimum size to 30 cm. The word "Dorsch" used in germanic languages for cod, means "dried fish". Since the vikings, dried cod has been an important foodstuff for nordic peoples and an important commercial merchandise. The fish is simply dries "Stockfisch" or cut and dried "Klippfisch". Coastal cod is also taken to market fresh and conserved in ice, and large quantities are sold as frozen fillets. Waste is also used for the production of fish flour. Every year 60,000 tonnes of cod liver oil are produced. Cod's roe is sold fresh or smoked, although a large proportion is sold as bait for sardine fishing. Annual captures of cod in the North Atlantic total around 1.5 million tonnes. United Kingdom,
290.000-390.000 tonnes;
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