Effects of geographical isolation and population size on genetic diversity of local populations of Alpine Accentor

由于高山樱草只在山顶繁殖，繁殖种群彼此隔离。为了研究该物种的遗传多样性，我们采集了11座山（Norikura山22只、Komagatake山3只、Myoko山6只、Tateyama山7只、Gassan山4只、yutatake山2只、Hakusan山4只、Senjyo山1只、Fuji山1只、Tyoukai山1只、Tubakuro山3只）54只的血液，并分析了mtDNA。线粒体区域的结构与其他鸟类相同。从飞驒山区种群采集的35个样本中，所有种群均与A、B和C三种单倍型具有共同特征，表明山区之间存在非地理上的分离。高山埃森哲单型多样性指数为0.56，低于红资料鸟类。与从其他鸟类中分离的微卫星位点相比，高山埃森哲的微卫星位点变异性极低。遗传变异低的原因可能是孤立种群小，出生亲缘性强，成鸟和幼鸟的回归率高。高山燕鸥是一种垂直候鸟，在高寒地区形成繁殖群，在越冬地形成鸟群。繁殖地和越冬地是相互独立的，因为没有证据表明繁殖地和越冬地之间保持着个体联系（群体组成和家庭关系）。如果越冬个体明年不返回出生地，繁殖种群的遗传变异就会很丰富。

Since the Alpine Accentor Prunella collaris breeds exclusively on the top of mountain, the breeding populations are isolated each other. To examine the genetic diversity of this species, we collected blood from 54 individuals on 11 mountains (22 birds on Mt. Norikura, 3 on Komagatake, 6 on Mt. Myoko, 7 on Tateyama, 4 on Gassan, 2 on Yatugatake, 4 on Mt. Hakusan, 1 on Mt. Senjyo, 1 on Mt. Fuji, 1 on Mt. Tyoukai and 3 on Mt. Tubakuro) and analyzed mtDNA. The mitochondrial regions hold the same structure as those of other bird species. All populations shared with A, B and C haplotypes identified from 35 samples collected at Hida mountain populations, indicating non-geographical separation between mountains. Index of haprotype diversity of Alpine Accentor was 0.56, which was lower than that of red-data bird species. Compared with the microsatellite loci isolated from other birds species, variability of the microsatellite loci of Alpine Accentor was extremely low. It is likely that low genetic variation is due to small isolated population, strong natal philopatory and high return rate of adult and youngThe Alpine Accentor is an altitudinal migrant bird, which forms breeding group in alpine zone and forms flock in wintering grounds. The breeding group and the winter flock are independent of each other because there was no evidence that individual associations (group composition and family bonds) were maintained between breeding and wintering sites. If wintering individuals do not return to the natal site next year, genetic variation of a breeding population would be rich.