Distribution, abundance, and biology of polar cod, Boreogadus saida (Lepechin 1773), in Icelandic waters

No abstracts are to be cited without prior reference to the author.

Distribution, abundance, and biology of polar cod, Boreogadus saida, was studied in the waters around Iceland based on material sampled during demersal fish surveys in March 1985-2011 and in pelagic 0-group surveys in August-September 1974-2003. Demersal polar cod were most often caught on the outer the shelf to the northwest of Iceland but during the years of highest abundance and widest distribution it was also caught on the north and northeastern shelves. Pelagic 0-group polar cod was only caught sporadically and confined to the waters over outer part of the northwestern shelf. Both distribution and abundance showed variations related to bottom temperature. Demersal polar cod was most widely distributed and peaks in abundance highest in the cold years of 1989-1999, 1994-1995 and 2002. A fourth peak in both abundance and distribution was observed during the somewhat warmer period of 2007-2009. On average highest numbers of polar cod per haul were caught at temperatures of 1.4° C and 0.14° C, and at depth ranges 55-100 m and 300- 400 m, respectively. The length of demersal polar cod ranged from 5-32 cm while the fish caught in the pelagic trawl ranged from 2.2-19 cm. The polar cod in north Icelandic waters most likely originates from east Greenland or even possibly Svalbard waters.