Life and death of the mountain hare in the boreal forest of Sweden

The mountain hare (Lepus timidus) is historically one of Sweden’s most appreciated game species. Nevertheless, little is known about how the mountain hare lives its life, especially in its main habitat, the boreal forest. This is probably due to the challenges involved in studying an animal with a low population density and solitary life style. The main objective of this thesis was to estimate several basic, and so far unknown, demographic parameters of relevance to the population dynamics of the mountain hare. The thesis is based on data from captured and radio-marked wild hares (73 adults and 48 leverets). In addition, one study also includes data from 65 released captive-reared leverets. Leveret survival was low. From two weeks of age they exposed themselves and became easy targets for a wide range of predators. Once they had established a home range their survival became comparable to that of adult hares. Adult hares showed high annual survival rates. The lowest seasonal survival was found in males during the mating season in spring. Predation, especially by the red fox, is the main cause of mortality for both leverets and adult mountain hares. Mountain hare survival was synchronized with the abundance of small rodents; as vole density decreased, hare mortality increased. My results suggest, in accordance with other studies, that mountain hare population dynamics in the boreal forest of Sweden are driven by predation as suggested by the alternative prey hypothesis. Even though the hares had large home ranges, the species may still show very local population dynamic patterns. During the study, none of the adults moved from their initial home range, and only a small proportion of the leverets clearly dispersed from their birth place. An individual’s contribution to coming generations will thus mainly be made in the area where it was born. I suggest that the hare’s accumulated experience of an area, rather than physical resources, may explain the adult hares’ annually sedentary behaviour and, in effect, their high survival rate. Within this “area of experience”, however, the hares tracked changing physical resource availability between seasons