Abstract
The 2011 Tohoku earthquake drastically changed human activities in parts of Fukushima Prefecture, Japan. The
subsequent tsunami damage and radioactive fallout from the Fukushima Daiichi nuclear power plant resulted in the abandonment
of agricultural land and towns, allowing the expansion of wild mammal populations into areas previously inhabited by their
domesticated relatives. This study examined possible hybridisation between wild boars and domesticated pigs in Fukushima.
We analysed the mitochondrial DNA sequences of 75 wild boars collected from Fukushima populations between 2014 and
2016. While 71 boars had Asian boar haplotypes, four boars identified as wild boars phenotypically had mitochondrial genomes
extremely close to that of European domesticated pigs, implying ongoing genetic contamination of wild boar populations from
feral domesticated pigs. This suggests the need for detailed genetic monitoring using nuclear DNA markers and population
management based on genetic data.
