Home-range sizes and altitude selection for arctic foxes and wolverines in an alpine environment

We compared the use of space and habitat by wolverines, Gulo gulo, and arctic foxes, Alopex lagopus, on the Snohetta plateau and surrounding mountains in south-central Norway. The arctic foxes used smaller annual home ranges than the wolverines, whose home ranges were among the largest yet reported for the species. In both species, resident males used larger home ranges than resident females. Arctic foxes used a much narrower, and higher, range of altitudes than wolverines, always above the tree line. Wolverines used lower altitudes in winter than in summer. Female wolverines showed pronounced seasonal peaks in their use of the peripheral areas of their home ranges. Both species showed an ability to cross at least some transportation corridors (road, rail, human settlements) in the area. The habitat available at Snohetta appears suitable for arctic foxes and does not explain the failure of the population to recover during 67 years of protection. Because of predation on domestic sheep, wolverines will probably be confined to a series of core conservation areas (CCA). At present densities (0.28-0.36 wolverines per 100 km(2)), the CCA surrounding Snohetta can contain from 36 to 50 wolverines.