Abstract
Seasonal variation in food selection has been documented in several species on voles (Rothestein and Tamarin 1977, Cole and Batzli 1979, Goldberg et al. 1980) with considerable implications for winter survival and population dynamics. In Microtus montanus a similar link may exist between growth, maturation, longevity, and population dynamics on the one hand and dietary composition on the other (e.g., Pinter and Negus 1965, Berger et al. 1981, Pinter 1988, Berger et al. 1992, Negus et al. 1992). Consequently, we undertook a study to investigate in detail the utilization of plant resources by the montane vole, Microtus montanus. The objectives of this project are twofold: (1) to identify the plant species that constitute the diet in natural populations of M. montanus and (2) to determine seasonal food preferences in relation to the availability of plant species and to the age, sex and cohorts of the montane vole.