The cod population in the Kattegat is at an historic low and outside safe biological limits. ICES advises that there should be no directed fisheries and bycatch and discards should be minimised. Fishing in the Kattegat over the past 100 years has led to profound changes, with certain species becoming extremely rare or even absent. Avoid eating cod from depleted stocks.
Cod belongs to a family of fish known as gadoids, which also includes species such as haddock, pollack, pouting and ling. It is a cold-temperate (boreal), marine, demersal (bottom-dwelling) species. Also found in brackish water. Their depth range is 0 - 600 m, but are more usually found between 150 and 200 m. They have a common length of 100 cm. Maximum length 200 cm. Maximum published weight 96 kg and a maximum reported age of 25 years. In the North Sea cod mature at 4-5 years at a length of about 50 cm. They spawn in winter and the beginning of spring from February to April. Spawning sites are in offshore waters, at or near the bottom (50-200 m depth) and at water temperatures of 0-12 C (preferred range 0-6C). May form spawning aggregations in the water column when temperatures are unsuitable. Different spawning areas may be used in subsequent years. Embryo development lasts about 14 days (at 6C) and larval phase about 3 months (at 8C). Fecundity ranges from 2.5 million eggs in a 5 kg female to a record of 9 million eggs in a 34 kg female. Sex ratio is nearly 50%, with slight predominance of females. Classified as a determinate multiple spawner. Older and larger cod have been found to produce larger eggs with neutral buoyancy at lower salinities. This can be crucial to egg and larval survival. Larvae are pelagic up to 2.5 months before settling on the bottom. The fish has a protruding upper jaw, a conspicuous barbel on the lower jaw (used to look for food), and light lateral line, curved above the pectoral fins. Predorsal distance is less than one third of total length; body depth about 1/5 of total length. Colour varies from brownish to greenish or gray dorsally and on upper sides, becoming pale and silvery ventrally. Peritoneum silvery. Distribution: North Atlantic and Arctic: Ungava Bay in Canada along the North American coast to Cape Hatteras; North Carolina in the western Atlantic. East and west coast of Greenland; around Iceland; from Barents Sea including the region around Bear Island along the European coast to Bay of Biscay. Widely distributed in a variety of habitats, from the shoreline down to the continental shelf. Juveniles prefer shallow (less than 10-30 m depth) sublittoral waters with complex habitats, such as seagrass beds, areas with gravel, rocks, or boulder, which provide protection from predators. Adults are usually found in deeper, colder waters. During the day, form schools and swim about 30-80 m above the bottom, dispersing at night to feed. Omnivorous; feed at dawn or dusk on invertebrates and fish, including young cod. Migrate between spawning, feeding and overwintering areas, mostly within the boundaries of the respective stocks. Migrations >200 km are rare occurrences.
Spawning stock biomass is at the historically lowest level since 2000, and is outside of safe biological limits (B< Blim) and suffering from reduced reproductive capacity. Recruitment in recent years has been among the lowest in the time series. In recent years reported landings do not represent total removals from the stock; unaccounted removals have been 5-8 times the reported landings or Total Allowable Catch (TAC). In 2009 Denmark and Sweden introduced protected areas on cod spawning grounds to help rebuild the stock. Despite a managment plan being in place since 2005 the stock biomass has continued to decline. ICES advises that there should be no directed fisheries and bycatch and discards should be minimised.
Kattegat cod are mainly landed by trawls and Danish seines. In recent years cod is caught as bycatch in the Nephrops fishery. Discarding of young cod and possibly also high-grading of marketable cod takes place. Since 2004 the use of trawls with codend mesh size below 90mm in the nephrops fishery has only been permitted if the net is fitted with a sorting grid. The use of the Swedish sorting grid has increased in 2009 and 2010 and it is now the main gear used in Swedish Nephrops fisheries. The increased use of the sorting grid has reduced discards of cod in Swedish fisheries in recent years. Further development and introduction of selective trawls with low catchability on cod is recommended. Total landings (2010) 155 t (of which 74% Nephrops trawl, 10% > 100 mm trawl, 8% gill nets). There is potential damage to the seabed by trawling. Trawling is also associated with discarding of unwanted fish, i.e. undersized and/or non-quota and/or over-quota species. Since January 2003 the basic minimum mesh size for towed gears for cod has been 120mm. The minimum landing size for cod in waters in Skagerrak/Kattegat is 30cm. In all other EU waters it is 35cm. The approximate size at which 50% of females first spawn is, however, 60 to 70cm. Choose gillnet or Danish seine-caught where available.
ICES Advice 2013, Book 6
(Based on method of production, fish type, and consumer rating: only fish rated 3 and below are included.)
Read what the consumer pages of the Good Fish Guide say about this species.
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