Levels of Aggression in Fluctuating Populations of the Prairie Vole, Microtus ochrogaster, in Eastern Kansas

Abstract
Levels of aggression, as seen through wounding, were examined throughout a density cycle of the prairie vole, Microtus ochrogaster, in eastern Kansas. Biweekly samples yielded 640 live-trapped voles for which reproductive and wounding assessments were made over a 23-mont:b period. At autopsy, the everted skin was examined for evidence of puncture wounds and scars caused by attacks from other small mammals. Wounds were graded by a wounding index and analyses performed by Chi-square tests. Levels of wounding were comparatively great in the winter season, in periods of intense reproduction, among males, and among adults. A model of population regulation based on the observed patterns of wounding is proposed.