Population genetics of Daubenton's bat (Myotis daubentonii) in the Archipelago Sea, SW Finland

Due to their reclusive nature, information on the population structure of many bat species is lacking or scarce. The pattern of small scale population genetic structure could reveal the degree of gene flow among colonies, and the evolutionary consequences of short-distance dispersal. In this study, we used nine microsatellite loci to assess the small-scale genetic population structure of Daubenton's bats in the Archipelago Sea comparing it to samples from sites elsewhere in Finland and Europe. The Archipelago Sea is a highly variable environment with possible dispersal barriers. Our results indicate a low level of population genetic structuring among the populations sampled. We found significant isolation by distance in both sexes, indicating a gradual increase of population differentiation across a large geographic scale. In Finland alone, isolation-by-distance was also found, with high levels of gene flow among local populations. Isolation-by-distance was stronger in females, suggesting that males disperse longer distances.