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.