Method of production - Caught at sea
Capture method - Demersal otter trawl
Capture area - North East Atlantic (FAO 27)
Stock area - North East Arctic (Barents and Norwegian Sea)
Stock detail - I and II
Fish type - White flat fish
For many years the advice for this stock is to reduce catches to allow the stock to rebuild. Although reference points for the stock are not determined stock status is considered to be low, and scientific advice to limit catches is being ignored, with TACs being agreed by the Joint Russian-Norwegian Fisheries Commission 20% above levels recommended by scientists. Greenland halibut is a long-lived species which can only sustain low exploitation.
This is an Arctic species which feeds in mid-water. Unlike most other flatfish, its 'blind side' is dark grey rather than white. Greenland halibut spawns in summer (April to June). It is a relatively slow-growing and long-lived species. Males become sexually mature when 7-8 years old and 55-65cm long and females when 9-11 years old and 65-80cm. They move into deeper water as they grow and can reach lengths of 120cm. Maximum reported age 30 years.
North East Arctic (Barents and Norwegian Sea)
Since 2001 ICES advice for this stock has been to reduce catches to rebuild the stock. No reference points are defined for this stock and only landings and survey trends of biomass are available. Although there are signs of improvement in stock biomass - estimates indicate a stable or increasing trend since 1992 - there is no information on the exploitation rate of the stock. ICES advice to reduce catches below 13,000t (the level below which stock size has previously increased) has been largely ignored by the two main fishing countries, Norway and Russia, and in fact the Joint Russian-Norwegian Fisheries Commission have set the TAC at 15,000t for the period 2009-2012. Several other countries continue to fish this species, although at much lower levels compared to Russia and Norway, which combined represent 90-95% of landings. Effective evaluation of the stock remains problematic due to persistent issues of uncertainty. ICES advice for 2014, as in the previous year, is that catches should not be allowed to increase above 15,000 t, the average catch for the last 10 years. ICES advises that catches should not be allowed to increase.
There are no explicit management objectives for this stock
In addition to directed longline and gillnet fisheries for Greenland halibut, the species is also taken as bycatch in trawl fisheries. Since 2004, when less restrictive bycatch regulations were introduced, it has been taken in directed trawl fisheries for other species - for example, once cod fishing has ceased during a trip. This has resulted in increased landings of the species by trawlers. However, in 2009, the Joint Russian-Norwegian Fisheries Commission cancelled the ban on a targeted fishery for this species and set a TAC of 15,000t for 2010-2012. Given the status of the fishery, this represents a potentially negative development. Trawl fishing for various species in deep water has been associated with significant damage to cold water coral (Lophelia) reefs, with the Norwegian Institute for Marine Research estimating that between 35-50% of reefs have been damaged by fishing activity. Any increased and targeted fishery for Greenland halibut should ensure adequate protection for this sensitive, slow growing and poorly understood ecosystem.
ICES Advice 2014, Book 3 http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2014/2014/ghl-arct.pdf
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