Size and overlap of home range in a high density population of the Japanese Field vole Microtus montebelli

Abstract

Relationships of size and overlap of home range with the population density in a flood plain population of Microtus montebelli (Milne-Edwards, 1872) with high density were examined from April to December 1993 using mark-recapture method. Population density in the study area was reached 280 males/ha nad 236 females/ha in summer. Although reproductively active voles were present throughout this study, more than half of females underwent reproductively resting period in summer. Main breeding seasons were spring and autumn when the density was relatively low. While the home range size of adult males did not decrease in summer when the population density was higher than in spring or autumn. In summer, males showed significantly larger degree of home range overlap than in spring or autumn, while home ranges of females overlapped little throughout this study. These results differed from those of the previous studies on this species, possibly due to much higher density in mountainous populations.