Genetic variability of American mink (Neogale vison) introduced from different places of origin

The American mink (Neogale vison; Patterson et al. 2021), a non-native species originally from North America, has successfully acclimatised and established wild populations across Europe, where it has largely displaced the native European mink (Mustela lutreola). Assessing genetic variability in invasive populations provides valuable insights into introduction history, colonisation dynamics, and the long-term viability of established populations. This study aimed to evaluate the genetic variability of different American mink subpopulations in Lithuania. Six microsatellite loci were analysed in 62 individuals sampled from three Lithuanian regions: Alytus, Šilutė, and Zarasai. The results revealed a total of 29 alleles across six loci, with heterozygosity levels varying among subpopulations. Šilutė showed the highest genetic diversity (Ho = 0.712; He = 0.730), while Zarasai exhibited a pronounced deficit of heterozygotes (Ho = 0.333; He = 0.656), consistent with a founder effect. STRUCTURE analysis identified the presence of two to four genetic clusters, suggesting that populations originated from multiple introduction sources and have undergone genetic admixture. These results highlight that introduction history and subsequent genetic mixing have increased the adaptive potential of this invasive species, thereby facilitating its successful establishment. Understanding these dynamics is crucial for developing management strategies to control mink populations and mitigate their impacts on the native biodiversity. Keywords: American mink; Neogale vison; Lithuania; genetic variability; microsatellite loci; invasive species