USE OF SPACE AND HABITATS BY MEADOW VOLES AT THE HOME-RANGE, PATCH AND LANDSCAPE SCALES

Using capture/recapture methods, we examined the spatial usage pattern s of Microtus pennsylvanicus within and between experimentally created habitat patches of three sizes (1.0, 0.25 and 0.0625 ha) and between a 20-ha fragmented and a 20-ha continuous habitat landscape. We tested the prediction that home ranges near patch edges would be qualitative ly different from those in patch interiors, and that the edge:interior habitat ratio could be used to make predictions concerning the disper sion and spatial use of individuals occupying different sized patches and between landscapes with different habitat structure. We found adul t females on patch edges to have larger and more exclusive home ranges , larger body sizes, longer residence times, and to reproduce at a hig her frequency than those in patch interiors. These ''edge effects'' al so appeared to be largely responsible for the greater proportion of la rger, reproductive females we found in small than larger patches and i n the fragmented than in the continuous habitat (control) landscape. T he selection of higher quality edge habitats by dominant females and t he relegation of sub-dominants to patch interiors provides an explanat ion for the observed differences in the distribution and performance o f females over patches and between landscapes.