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 classified as having full reproductive capacity or as healthy in 2013 is now assessed as below target. Fishing mortality remains above target, i.e. it 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 they 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, cod 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 commercial species 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) has been relatively stable since 2000, and mostly below Bpa. Fishing mortality in 2013 is estimated to be above FMSY and the stock at risk therefore of being overfished. Removals of cod in recreational fisheries in the Baltic are substantial. ICES advises on the basis of the MSY approach that the total commercial catches should be no more than 8793 tonnes in 2015 (In 2014 advice was that commercial landings should be set at 17,037 t). Also Measures should be implemented to protect the local spawners in Subdivision 22.
The fishery is managed through Total Allowable Catch (TAC), effort, seasonal fisheries restrictions, and technical measures. The cod fisheries in the western Baltic have also been regulated since 2009 by a seasonal closure from 1 April to 30 April to protect spawning aggregations of cod. To decrease discards, a “Bacoma” codend with a 120 mm mesh was introduced by the International Baltic Sea Fisheries Commission (IBSFC) in 2001 in parallel to an increase in diamond mesh size to 130 mm in traditional codends. The expected effect of introducing the “Bacoma” 120 mm exit window was nullified by compensatory measures in the industry. This was to some extent explained by the mismatch between the selectivity of the 120 mm “Bacoma” trawl and the minimum landing size. In October 2003, the regulation was changed to a 110 mm “Bacoma” window. This was expected to enhance compliance and to be in better accordance with the minimum landing size, which was changed from 35 to 38 cm in the same year. As of 1 January 2010 the “Bacoma” 120 mm was re-introduced along with an extended “Bacoma” window (5.5 m) to further decrease discarding, and the minimum landing size was kept at 38 cm. The increase in minimum landing size from 35 to 38 cm has increased discard rates. 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. Although the catches for most years since 2008 have been below the level advised by ICES the fishing mortality has not declined as anticipated. Due to this effect it is considered that following the relative F reductions (10%) stipulated in the plan will not reduce F. A new management plan is under development.
Total catch of cod in this area (2013) is 17.5 kt, where 13.0 kt are commercial landings, 2.3 kt discards, and 2.3 kt partial recreational catch. The main portion of cod is taken by trawl (60%), but also gillnet (40%) and to a minor extent longline and Danish seine. There is potential damage to the seabed by trawling. Trawling also associated with discarding of unwanted fish, i.e. undersized and/or non-quota and/or over-quota species. Bycatch consists mainly of flatfish, with flounders being the most abundant. 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 - 70 cm.
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 2014, Book 8 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2014/2014/cod-2224.pdf
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