Patterns of Visitation in Prairie Voles (Microtus Ochrogaster) Reveal a Role for Males in Population Regulation

Spacing behavior appears to play a role in population regulation of microtine rodents. We used information gathered from livetrapping at nests and the periphery of home ranges of prairie voles (Microtus ochrogaster) to continue our examination of the role of spacing behavior in population regulation. Resident and nonresident adult males captured at the outskirts of home ranges were reproductive rather than nonreproductive and did not differ in body weight. Although the majority of adult females were reproductive, the pattern was more pronounced for residents. The presence of adult males in a resident group deterred visits by nonresident males. By excluding nonresident males from the home range, resident males appeared to influence the reproductive condition of their daughters; if females became reproductive while living at home, they did so at an earlier age when living in groups where resident males were absent than where resident males were present. From these results we suggest that adult males play a role in setting breeding density in natural populations of prairie voles.