Genetic Population Structure of Wild Boars (Sus scrofa) in Fukushima Prefecture

SIMPLE SUMMARY: After the Fukushima Daiichi nuclear power plant accident, a highly contaminated area with radionuclide appeared and was designated a difficult-to-return zone (DRZ). After that, the increase in number of wild boars (Sus scrofa) has been pronounced in DRZ, and the spread of highly contaminated wild boars into other areas is cause for concern. Understanding the population structure based on the genetic diversity of wild boars in Fukushima provides important information for the management of the animals. In this study, we carried out MIG-seq analysis to clarify the dispersal and gene flow of the local wild boar population and uncover the genetic population boundary in Fukushima. We obtained 328 single-nucleotide polymorphisms from 179 wild boars. Based on STRUCTURE analysis, we found significant genetic differences between groups of wild boars inhabiting in the east and west, divided by the Abukuma River. Since the urbanized area is concentrated along the Abukuma River in Fukushima, both the Abukuma River and the urbanized area are likely to interfere in the migration and dispersal of wild boars. Furthermore, our results indicate that the population in the western area was established by the migration from other neighboring prefectures rather than by that from the eastern group of Fukushima Prefecture. ABSTRACT: We aimed to reveal the dispersal and gene flow of the local wild boar (Sus scrofa) population and find their genetic boundary in Fukushima Prefecture. After the nuclear incident in 2011, the land was considered a difficult-to-return zone, and the increase in the number of wild boars was pronounced. To provide an effective management strategy for the wild boar population, we used multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq) and clarified the genetic structure of wild boars. We obtained 328 single-nucleotide polymorphisms from 179 samples. STRUCTURE analysis showed that the most likely number of population cluster was K = 2. Molecular analysis of variance showed significant genetic differences between groups of wild boars inhabiting in the east and west across the Abukuma River. The migration rate from the eastern population to the western population is higher than in the reverse case based on BayesAss analysis. Our study indicates that both the Abukuma River and anthropogenic urbanization along the river may affect the migration of wild boars and the population in western was established mainly by the migration from other neighboring prefectures.