The polar cod of Porsangerfjorden, Norway; revisited

The polar cod, Boreogadus saida (Lepechin, 1774) (Gadidae), is a genuinely arctic fish species, which was recorded from Norwegian waters, i.e. the Austerbotn Basin of Porsangerfjorden, for the first time in 1967. Whether the polar cod in Austerbotn are strays from arctic waters or represent a population of its own is a matter of debate. Here we review the scarce information available and provide circumstantial hydrological and biological evidence for a remnant population of polar cod that might have been isolated in Austerbotn since the late Weichselian glaciation (approximately 10 000 years BP) or, at least, since the ice winter 1902–03.