Geographic Variation in Crow Calls of the Japanese Green Pheasant Phasianus colchicus

I attempted to detect differences in crow calls of the Japanese Green Pheasant Phasianus colchicus among local populations in seven prefectures throughout Honshu and Kyushu, covering the distributions of four subspecies in Japan. Vocal learning may lead to the relatively rapid development of differences in vocalization patterns among certain bird populations, however, vocal learning is absent in pheasants (Order Galliformes). The acoustic structure of crow calls in the seven populations exhibited geographic variation. Hybridization between subspecies, caused by repeated artificial releases, within a region seemed to not be a factor influencing this geographic variation.