Spacing system of the tundra vole (Microtus oeconomus) during the breeding season in Canada's western Arctic

We studied the spacing system of a population of tundra voles, Microtus oeconomus, living in wet meadows near Pearce Point, Northwest Territories, using both radiotelemetry and live trapping. The home ranges of sexually active males were larger than female home ranges and males had no spatial overlap with each other. Most females overlapped with other females but with only one male. The mating system was therefore probably polygynous. We suggest that the mating and spacing systems of this species in summer are a consequence of the differences in natal philopatry between females and males.