Greenland halibut is widely distributed in the Barents Sea. Catches are highest along the continental slope where the main spawning grounds are located (Figure 4.3.45). The northern and north-eastern part of the Sea is regarded as a nursery area for the stock (Figure 4.3.46). This species is also relatively abundant in many of the deep channels running between shallow fishing banks of the Barents Sea (ICES AFWG, 2014).
At present, there is no ICES-accepted assessment for the Greenland halibut stock. This is largely due to age-reading problems and data discrepancies. In the absence of defined reference points the stock cannot be fully evaluated. This long-lived species can only sustain low levels of exploitation, and the stock has been at low to intermediate levels of abundance for several years. Despite some signals in recent years that the stock may be increasing, indications from different fishery-independent surveys are inconsistent (Figure 4.3.47) (ICES AFWG, 2014).
Figure 4.3.47a. Northeast Arctic Greenland halibut. Biomass (swept area) estimate of the mature female biomass (Norwegian Greenland halibut survey along the continental slope in August and Russian autumn trawl survey).
Figure 4.3.47b. Northeast Arctic Greenland halibut. Total biomass estimates from the Norwegian Greenland halibut survey along the continental slope in August and Russian autumn trawl survey. No Norwegian survey was conducted in 2010 or 2012