Cod, Atlantic Cod
Method of production - Caught at sea
Capture method - Gill or fixed net
Capture area - Baltic Sea (FAO 27)
Stock area - Baltic West
Stock detail - Subdivisions 22-24
Fish type - White round fish
The Spawning Stock Biomass (SSB) in the western Baltic is classified as having full reproductive capacity or as healthy. However current fishing mortality is too high and the stock at risk therefore of being overfished. Choose otter trawled fish as there is no incidence of harbour porpoise bycatch associated with this method compared to that of gillnetting in the Baltic.
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 0-6°C). 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 6°C) and larval phase about 3 months (at 8°C). 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.
Cod is overall the most important species in the commercial fisheries in the Baltic Sea. The abundance and distribution of cod has varied considerably over time due to biological as well as anthropogenic causes. Two populations are present in the area: eastern and western Baltic cod. These cod stocks have different morphometric characters and population genetics. They overlap in the area near Bornholm Island. The eastern cod occurs in the central, eastern and northern part of the Baltic but not in significant numbers north of the Aalands Islands. The western cod inhabits the areas west of Bornholm island including the Danish Straits. The eastern population is the largest (90% eastern -10% western population), but some fluctuations in the relative proportions of the cod stocks occur due to differences and changes in exploitation level and recruitment. The Spawning Stock Biomass (SSB) in Subdivisions 22-24 (western stock) is classified as having full reproductive capacity. However current fishing mortality is above MSY and the stock at risk therefore of being overfished. The management plan agreed in 2007 aims to reduce Fishing Mortality (F) by 10% each year until the target F is reached. Although the plan is evaluated by ICES as being in accordance with the precautionary principle it should be noted that F in the management plan is much larger than the current estimate of F MSY. Removals of cod in recreational fisheries in the Baltic are substantial. ICES advises commercial landings should be set at 17,037 t in 2014.
The main portion of cod is taken by trawl, but also gillnet and to a minor extent longline and Danish seine. The minimum landing size for cod in EU waters is 35 cm and 38 cm in the Baltic. The approximate size at which 50% of females first spawn is however 60 to 70 cm. Gillnets in the Baltic are associated with bycatch of endangered harbour porpoises.
Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below . Click on a name to show the sustainable options available.
ICES Advice 2013, Book 8; The Net Effect. A WDCS Report for Greenpeace. Ross and Isaac (2004); The Price of Fish: A review of cetacean bycatch in fisheries in the north-east Atantic. L Nunny (2011).
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