Diverse rates of gene flow and long-distance migration in two moose Alces alces subpopulations in Europe

Abstract

We assessed migration rates and gene flow amongst 16 local demes and six larger groups of moose identified by a previous microsatellite study across the entire European range of the species. The most important barrier to gene flow, the Baltic Sea along with the mountainous region in northern Fennoscandia, separates two genetically distinct moose subpopulations—the Scandinavian and the continental subpopulations—that originate from different glacial refugia. Our results showed that moose effectively migrated over long distances, but statistically significant gene flow was shorter in the Scandinavian (300–400 km) compared to the continental subpopulation (400–500 km). The admixture rates in local demes were markedly lower in the Scandinavian, than in the continental part of the moose range. Weaker gene flow amongst local demes in Scandinavia resulted from the major barrier of the Scandinavian Mountains. In the generally panmixed continental subpopulation of moose, two demes—one in NE Poland and another in the Kirov Oblast, Russia showed slightly hampered gene exchange with neighbouring demes, whereas one deme, in Arkhangelsk region, NE part of European Russia, appeared to have very high gene flow into other demes. Different evolutionary and demographic histories, population densities and land topography (large rivers) could have contributed to the low level barriers to gene flow in the continental subpopulation of moose.