Genetic diversity and genetic structure of Northern Goshawk (Accipiter gentilis) populations in eastern Japan and Central Asia

Abstract

Japanese goshawk was classified as a vulnerable species in the Red Data Book. There have been possibilities of a decrease of genetic diversity accompanied by habitat loss and genetic pollution due to hybridization with escaping imported goshawks. In this paper, genetic diversity, gene flow and conservation of Northern Goshawk (Accipiter gentilis) in Japan are discussed and compared with that in Central Asia. We used 11 newly developed microsatellite markers and also adopted six previously published markers. Genetic diversity was shown to be maintained with 0.58 as mean heterozygosity and 3.95 as mean allelic richness. The degree of genetic differentiation across all populations was low (Nei’s genetic differentiation index = 0.036, Wright’s genetic differentiation index = 0.039), possibly due to gene flow via adjacent regions (average number of migrants = 4.26; 0.68–20.30). However, it is possible that slight differentiation resulted from the short divergence time and/or inflow of escaping imported individuals. We recommend that goshawks in eastern Japan should be managed as a single unit. They do not appear to be under threat genetically at present, but there is the potential for rapid loss of genetic diversity. For future conservation, investigations of dispersal routes and actual conditions of gene flow are also recommended. To prevent further inflow of escaping goshawks into natural populations, it is desirable to reduce importation of goshawks and to enact a regulation obliging purchasers to register imported goshawks.