Genetic population structure of the northern shrimp (Pandalus borealis) along the Norwegian coast

Abstract

The coastal shrimp (Pandalus borealis) represent an important income for a small-scale fishery. The more economical important fishery of shrimp is located offshore. There is sparse information and literature regarding the coastal shrimp, and it is a lot we do not know about the species that inhabits our coast and fjords. Genetic research will provide more information on the species in these areas. Genetic investigation using microsatellite markers revealed three divisions or clusters of shrimps among the samples included in this study: the Barents Sea, Troms-Trøndelag and Vancouver (reference sample). Finnmark fjords showed to be influenced with both the Barents Sea group and the coastal Troms-Trøndelag group. A clear border, however, was found between the Barents Sea and Troms-Trøndelag. The Finnmark fjords samples showed varying degrees of genetic divergence from the Barents Sea, some being significant others not. The general trend showed that the inner eastern Finnmark locations and all fjords from Laksefjorden and south was significant different from the Barents Sea. Genetic population structure between fjords did not display any general trend, despite the difference between coastal populations in Finnmark and Troms-Trøndelag. The only fjords that displayed significant different genetic structure within, was the Varangerfjord in eastern Finnmark. The finding of genetic different coastal shrimps in Troms-Trøndelag indicate that they should be considered as a stock of their own. The Finnmark fjords also differ in some degree from the Barents Sea, and there should therefore also be considered further if this population should be considered as a separate stock.