USE OF SPACE AND HABITATS BY THE EASTERN CHIPMUNK, TAMIAS-STRIATUS

Regression analyses showed a significant, positive association between capture frequency of eastern chipmunks (Tamias striatus) and open-understory and closed-overstory habitats. Analyses within individual home ranges, however, showed that distance from burrows explained twice the variation in frequency of captures than did microhabitat structure (33 and 16% of the variation, respectively). Chipmunks used microhabitats in a spatially variable manner and according to some of the same rules that determine food choice in central-place foragers (i.e., they spent more time near to than far from burrows) and were more discriminating in use of microhabitat at greater than at closer distances. Capture frequency of transient (nonresident) chipmunks was more highly correlated with microhabitat than was that of residents. Analysis of patterns of spatial usage by individuals offers an alternative to population-level approaches and provides a more mechanistic basis for interpreting the use of both space and microhabitats.