Small Mammal Capture Efficiencies Among Three Trap Types

Abstract

Capture rates of small mammals were compared among live, pitfall, and snap traps to determine the relative efficiency of trap types by species and mammal groups. Three small mammal trap types were employed concurrently in each of 53 sites representing major vegetation types of Montana. Shrews (Sorex spp./, sagebrush voles (Lemmiscus curtatus), and northern pocket gophers (Thomomys talpoides/ were captured more often than expected in pitfall traps. Chipmunks (famias spp.) and deer mice(Peromyscus maniculatus) were caught significantly more often by live traps. The capture rate for voles (Microtus spp.) did not differ significantly among trap types. We conclude that a combination of trap types must be used to accurately assess small mammal species composition, diversity, and abundance.