Analysis of Genetic Structure and Genetic Diversity in Japanese Black Kite Population Using mtDNA

The black kite (Milvus migrans) is widespread in the “Old World” and is a common raptor species in Japan. However, examples of regional population dynamics and genetic research are limited. To reconsider the natural history and current status of the black kite in Japan, we analyzed the genetic diversity of the Japanese black kite population. We collected 59 black kite samples from 22 locations across Japan and extracted DNA; 1585 bp sequences of the cytochrome b and control region, which form part of the mitochondrial DNA, were determined for genetic analysis of the population. Consequently, six haplotypes were detected in 59 individuals, 50 of which had the same major haplotype, namely, Mm1. Moreover, the genetic analysis indicated that the Japanese black kite population would fit the population expansion model. Phylogenetic analysis using sequences obtained in this study or from a DNA database indicated that the Japanese black kite population can be divided into two groups: (1) Mm1 and its close haplotypes and (2) Mm5. The sequence of Mm1 was exactly the same as that of black kite in Pakistan, India, and Korea, suggesting that this haplotype is generally widespread in East Eurasia, and that the ancestral haplotype of the Japanese population likely migrated from continental East Asia and expanded its distribution throughout Japan. In summary, we found that the black kite population in East Eurasia, including Japan, is composed of at least two lineages.