Dalén L, Kvaløy K, Linnell J D C, Elmhagen B, Strand O, Tannerfeldt M, Henttonen H, Fuglei E, Landa A, Angerbjörn A
Department of Zoology, Stockholm University, S-106 91 Stockholm, Sweden.
Mol Ecol. 2006 Sep;15(10):2809-19. doi: 10.1111/j.1365-294X.2006.02983.x.
The arctic fox (Alopex lagopus) in Scandinavia is classified as critically endangered after having gone through a severe decline in population size in the beginning of the 20th century, from which it has failed to recover despite more than 65 years of protection. Arctic foxes have a high dispersal rate and often disperse over long distances, suggesting that there was probably little population differentiation within Scandinavia prior to the bottleneck. It is, however, possible that the recent decline in population size has led to a decrease in dispersal and an increase in population fragmentation. To examine this, we used 10 microsatellite loci to analyse genetic variation in 150 arctic foxes from Scandinavia and Russia. The results showed that the arctic fox in Scandinavia presently is subdivided into four populations, and that the Kola Peninsula and northwest Russia together form a large fifth population. Current dispersal between the populations seemed to be very low, but genetic variation within them was relatively high. This and the relative F(ST) values among the populations are consistent with a model of recent fragmentation within Scandinavia. Since the amount of genetic variation is high within the populations, but the populations are small and isolated, demographic stochasticity seems to pose a higher threat to the populations' persistence than inbreeding depression and low genetic variation.
斯堪的纳维亚半岛的北极狐（Alopex lagopus）被列为极度濒危物种，在20世纪初其种群数量经历了严重下降，尽管受到了超过65年的保护，但仍未能恢复。北极狐具有很高的扩散率，常常远距离扩散，这表明在瓶颈效应之前，斯堪的纳维亚半岛内可能几乎没有种群分化。然而，最近种群数量的下降可能导致了扩散减少和种群碎片化增加。为了对此进行研究，我们使用了10个微卫星位点来分析来自斯堪的纳维亚半岛和俄罗斯的150只北极狐的遗传变异。结果表明，目前斯堪的纳维亚半岛的北极狐被细分为四个种群，而科拉半岛和俄罗斯西北部共同构成了第五个大种群。目前种群之间的扩散似乎非常低，但种群内部的遗传变异相对较高。这以及种群之间相对的F(ST)值与斯堪的纳维亚半岛近期碎片化的模型一致。由于种群内部的遗传变异量很高，但种群规模小且孤立，与近亲繁殖衰退和低遗传变异相比，人口统计学随机性似乎对种群的持续存在构成了更高的威胁。
