Skate, Norwegian or Black
Method of production - Caught at sea
Capture method - All applicable methods
Capture area - North East Atlantic (FAO 27)
Stock area - All Areas
Stock detail - I-IX
Fish type - White flat fish
Skates and rays are inherently vulnerable to overfishing due to slow growth rates, late maturation and low fecundity. Although little is known about the stock status or biology of Norwegian skate, it is likely to be highly vulnerable to over-exploitation given its large body size, slow growth, time taken to mature, and low intrinsic rate of population increase. Avoid eating.
Norwegian skates belong to the Rajidae family which includes skates and rays. The Norwegian skate is a large shelf and slope species, growing to a maximum length of 200cm. Size and age at maturity and maximum age is unknown. It is endemic to the northeast Atlantic, found off Norway, southern Iceland, around Rockall Trough.
The Norwegian skate is a deep water species and its stock status is uncertain. Little information is generally available on the landings of deepwater skates. ICES reports that, although there are historical records from Rockall and the Norwegian Deep, where it was known to have occurred, there have been no recent records of the species in these areas. This is one of the largest skates and as such has low productivity and high catchability, similar to other large skates that have been heavily impacted by even moderate levels of bycatch. Given the species high intrinsic vulnerability, an absence of management or conservation measures and its apparent disappearance from Rockall and the Norwegian Deep it is unlikely that this species can be fished at a sustainable level. IUCN Red List status: Near Threatened (2008).
There is no specific management plan for demersal elasmobranchs and no management plan for this stock or any skate stock in the ICES area. Given the regional differences in skate assemblages and fisheries, ICES recommends that management measures for elasmobranchs be devloped on a case-by-case basis. Currently these species are managed under a common Total Allowable Catch (TAC). There is a combined TAC in place for all species of skate and ray in the North and Norwegian Seas. Previously there was no requirement to report species of skate and ray individually so they were reported together as 'skates and rays', which makes it difficult for scientists to evaluate the stock status of different skate and ray species. However, from 2008 EU countries must report species specific landings of major skate and ray species in the North Sea and Norwegian Sea, so that in the future scientists will be able to advise on species specific catches. There are also prohibitions on fishing for, retaining and landing some species, including the most severely depleted species taken as bycatch in mixed demersal fisheries. ICES does not advise that general or species specific TACs be established at present because they are not the most effective means to regulate these bycatch species. TACs alone may not adequately protect these species as there are differences amongst species in their vulnerabilities to exploitation and a restrictive TAC may lead to discarding. Instead seasonal and/or area closures, effort restrictions and measures to protect spawning grounds for example are recommended. In 2007, Fisheries Science Partnership projects (fishermen and scientists working together) were conducted to investigate discard survival rates in trawl fisheries to find out the survival rate for skates and rays that would be discarded with the introduction of a maximum landing length. The projects also aimed to develop species identification onboard and contribute to improved data collection. The Skate and Ray Producers Association has recently been working to improve the lack of species specific data by reporting their catches by species, into a central database. This follows previous collaborative work with the Shark Trust and Seafish Industry Authority, to produce an identification guide to help distinguish different species.
Skates and rays form an important component of mixed demersal fisheries, taken as bycatch in beam and otter trawls, in seine fisheries and also in targeted fisheries using lines and set nets. Also targeted by sea anglers. No Minimum Landing Size (MLS) is specified for skates and rays in EU waters outside 6 miles. MLS specified in some coastal waters of England and Wales, e.g. Kent and Essex Sea Fisheries District, 40cm (wing to wing), South Wales 45cm, Cumbria SFC 45cm. Under current EU legislation, where a directed fishery for skates takes place, a mesh size in the cod-end of no less than 28cm is required and no less than 22cm in the rest of the trawl. There is a potential for damage to the seabed from trawling. Trawling is also associated with discarding of unwanted fish, i.e. undersized and/or non-quota and/or over-quota species.
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