Jirkov I.A. 2013. Biogeography of the Barents Sea benthos // Invertebrate Zoology. Vol.10. No.1: 69–88 [in English].
Department of Hydrobiology, Moscow Lomonosov State University, 119899, Moscow, Russia, e-mail: email@example.com
Key words: biogeography, the North Polar Basin, the Barents sea, Arctic, Polychaeta.
ABSTRACT: Since the mid-19th century, the biogeographical boundary of the Arctic has been drawn through the Barents Sea. Nevertheless, there is still no general consensus on its position, or what an Arctic species is. This is both because of the use of differences in criteria for drawing the biogeographical boundaries and the lack of data on species distribution in the region. Initial schemes were constrained by being based upon abiotic factors in determining the position of boundaries. A detailed chorological analysis, based mainly on polychaetous ranges, shows that within the Sea, the ranges of different groups of species are complementary to each other like parts of jigsaw puzzle. And the real pattern of species distribution differs from the simple scheme dividing the Barents Sea into Arctic and boreal sublittoral regions. For example, some Arctic species are distributed within the Barents Sea in a very similar manner to boreal ones. The distribution of some (shelf) Arctic species within the Barents Sea is indistinguishable from that of some Arctic-Pacific (i.e. arcto-boreal) species. The distribution of deep-sea and eurybathic species in the Barents Sea is complementary to distribution of shelf species and this phenomena does not connect with depth. Species entering the Barents Sea from the southwest (“boreal” species) are not a homogenous group as well as “arctic” species. Boreal species can be splitted into at least into inshore species inhabiting tidally mixed inshore water masses and outer shelf species inhabiting stratified shelf water masses. The latter, in their turn, also can be divided into several groups with different ranges within the Barents Sea. A scheme of biogeographical regionalization of the Barents Sea is proposed, based exclusively on chorological data. This scheme differs drastically from the earlier published ones. The main differences are: (1) species range typification has been made on the base of species distribution within the Barentz Sea only, instead of the whole World Ocean; (2) the fauna has been splitted in nine biogeographic groups instead of usual three (arctic, boreal and arcto-boreal).