The last years there has been a reduction in the amount of fishing vessels and this has increased the stock. The Norwegian fisheries in the EU, Faroe and Iceland Economic Zones are regulated by quotas and bilateral agreements.
Based on historical catch per unit of effort (CPUE) there’s a continuous decline from 1998 to 2004. From 2004 until 2009 there has been an increasing CPUE. The assessment is based on CPUE trends and the harvest is influenced by regulations aimed at other benthic species, e.g. cod and haddock. For 2010 the quota was set to 5000 tons in ICES’ areas I and II (Norwegian Sea and Barents Sea). For the North Sea the advice is 5000 tons.
Management and technical regulations of the fishery
For vessels from other countries there’s an annual quota in the Norwegian Zone. While the Norwegian vessels get quotas in other zones negotiated through bilateral agreements.
The tusk fishery in Norway is regulated through access limitations and by gear and area regulations.
Ecosystem/Biology
Tusk is considered a benthic species preferring rocky bottom on the continental shelf and on the slope from 100 until 1000 meters. The diet seems to be fish and crustaceans. Tusk has a northerly distribution compared with e.g. ling and blue ling. In the northeast Atlantic, the range extends from southern Ireland to Svalbard and the Kola Peninsula.
Tusk is abundant around Iceland and the Faroe Islands and in the deeper parts of the North Sea and Skagerrak. It is also common in the northwest Atlantic, off Greenland, and along the Reykjanes Ridge.
Spawning is widespread. The age of first maturation is eight to ten yrs, but varies within its geographic range. Maximum age is uncertain, but it can exceed 20 years, maximum length is about 100 cm, maximum weight about 9 kilos.
It is likely that several populations are found within its wide distribution area, but currently there is insufficient evidence to delineate populations. Very little is known about migrations. The species does not seem to form aggregations, e.g., during spawning or wintertime.
About the fishery
Tusk has been harvested for centuries over most of its range, often taken as a by-catch species in other directed fisheries.
Tusk is taken in mixed fisheries with ling and as a by-catch in fisheries for cod, mainly in long line and gillnets fisheries but there are also by-catches by other gears, i.e. trawls and hand line. From 2000-2009 an average of 90 per cent of the Norwegian landing was caught by long liners and 8 per cent by gill nets. Other nations catch tusk as a by-catch in trawl fisheries.