RELATIVE ABUNDANCE AND HABITAT ASSOCIATIONS OF SMALL MAMMALS IN CHAMBERLAIN BASIN, CENTRAL IDAHO

We sampled small mammal populations and measured habitat structure in forested and non-forested habitats in the wilderness of central Idaho over a 5-year period using pit and snap traps. Although results from p it and snap trapping differed for northern pocket gophers (Thomomys ta lpoides), capture rates for the two methods were similar across habita ts for the other common species. Southern red-backed voles (Clethriono mys gapperi) and shrews (Sorer vagrans and S. cinereus) were the most common species captured. Spruce-Gr forest exceeded other habitats in t he abundance of small mammals while all sites had low species richness (s = 4-7). Habitat associations of the common small mammals (southern red-backed voles, shrews, deer mice (Peromyscus maniculatus), and yel low-pine chipmunks (Tamias amoenus)) differed, based on both broad pat terns and microhabitat gradients. Our data corroborate the results of other investigations by demonstrating the relatively low abundance of small mammals in subalpine habitats of the Rocky Mountains. Furthermor e the differences in small mammal communities among forest types sugge sts a mosaic pattern of small mammal communities in the Rockies which results from the patchy nature of forests in this region.