title: Genetic variability and structure of the water vole Arvicola amphibius across four metapopulations in northern Norway.
abstract: Water vole Arvicola amphibius populations have recently experienced severe decline in several European countries as a consequence of both reduction in suitable habitat and the establishment of the alien predator American mink Neovison vison. We used DNA microsatellite markers to describe the genetic structure of 14 island populations of water vole off the coast of northern Norway. We looked at intra- and inter-population levels of genetic variation and examined the effect of distance among pairs of populations on genetic differentiation (isolation by distance). We found a high level of genetic differentiation (measured by F ST) among populations overall as well as between all pairs of populations. The genetic differentiation between populations was positively correlated with geographic distance between them. A clustering analysis grouped individuals into 7 distinct clusters and showed the presence of 3 immigrants among them. Our results suggest a small geographic scale for evolutionary and population dynamic processes in our water vole populations.
authors.affiliation: Department of Biology, Centre for Conservation Biology, Norwegian University of Science and Technology Trondheim, N-7491, Norway.
authors.forename: Claudia
authors.initials: C
authors.lastname: Melis
authors.forename: Asa Alexandra
authors.initials: AA
authors.lastname: Borg
authors.forename: Henrik
authors.initials: H
authors.lastname: Jensen
authors.forename: Eirin
authors.initials: E
authors.lastname: Bjørkvoll
authors.forename: Thor H
authors.initials: TH
authors.lastname: Ringsby
authors.forename: Bernt-Erik
authors.initials: BE
authors.lastname: Sæther
keywords: Dispersal; genetic structure; isolation by distance; microsatellite; patchy habitat