Sexually dimorphic aspects of spontaneous activity in meadow voles (Microtus pennsylvanicus): effects of exposure to fox odor.

In this study, a multivariate analysis of the locomotor activity of adult, breeding male and female meadow voles (Microtus pennsylvanicus) was conducted. Overall, male voles made more movements and spent more time in the center of the activity chambers than did female voles. The authors further investigated the effects of brief exposure (3 min) to predator (red fox [Vulpes vulpes]) odor and various control odors (butyric acid, extract of orange) on subsequent activity. Control odors had no effects. Immediately following exposure to the fox odor, male voles exhibited significantly lower levels of activity and decreased center time. No significant changes in any activity variable were observed in the female voles following exposure to fox odor. This study provides evidence for sex differences in both basal activity levels of meadow voles and activity following exposure to a predator odor.