The Arctic fox Alopex lagopus semenovi from Mednyi Island. Ecology of insular population [Russian]

摘要

The population of Arctic foxes on Mednyi Island (Commander Islands) has been isolated since the Pleistocene on a small island in the ice-free area of the North Pacific. Therefore, this population is protected both against predators and imigrating arctic foxes. The data on the structure of groups, dispersal, and survival of the island arctic fox are presented. About 35% of the families are combined into large groups, including 3-6 adult animals: a male, 1-3 lactating females, and a helper (ussually a yearling female from the same family). However, the foxes of Mednyi Island occupy small home ranges. The mobility of the Arctic fox is restricted both by the area of this island (187 km(2)) and social consraints. The majority of females always live within their natal range or in adjacent one.