Analysis of the genetic diversity and structure of the Eastern Marsh Harrier in Japan using mitochondrial DNA

The Eastern Marsh Harrier (Circus spilonotus) is a raptor and inhabitant of East Asia, including Japan, and is classified as endangered (class IB) in Japan. The aim of this study was to reveal the genetic structure of a C. spilonotus population among several breeding sites, and to estimate whether the current population contains sufficient genetic diversity. We sequenced 1142 base pairs of the mitochondrial DNA of Eastern Marsh Harrier among 37 individuals sampled during the breeding season and four individuals sampled during winter. In total, seven variable sites were found in the control region, and we detected nine haplotypes among the 41 individuals. Hachirogata, Akita prefecture in Japan, was found to be the core breeding area for the Eastern Marsh Harrier as all haplotypes were detected there. The results of network and mismatch distribution analyses indicated that the Eastern Marsh Harrier did not experience a genetic bottleneck in the past, rather it experienced a recent population expansion. In addition, comparisons with other raptors revealed a rich genetic diversity in the Eastern Marsh Harrier population in Japan.