ИСТИНА

The decline of arctic fox populations in Fennoscandia has been attributed to two main causes: the probably climate related scarcity of lemming peak years in the last decades and the increase of the competitively superior red fox. On the contrary in most of the wide Russian tundra regions arctic foxes are common. We investigate the state of a population in the southern Arctic, a tundra zone which is particularly exposed to climate induced changes and influences from more southern biome. Den survey data from seven years at Erkuta tundra monitoring site in southern Yamal (N 68.2°, E 69.2°; bioclimatic subzone E) show that the foxes are reproducing nearly every year. The number of occupied dens does not change much and is not strongly correlated to the small rodent dynamics, which are characterized by low amplitude fluctuations in a community dominated by voles. In addition to small rodents, a rich guild of medium sizes herbivores comprising hare, willow grouse and musk rat, as well as numerous waterfowl may provide resources for the arctic fox. Instead of behaving as “lemming foxes” typical for the Siberian tundra, we hypothesize that this population is a relatively stable inland population relying on a wide variety of prey. Red foxes are present in the study area, but in much lower numbers than arctic foxes. Using an ecosystem based approach we aim at describing the state of this arctic fox population in a changing ecosystem, and want to understand how stable the present state is.