Figure 4. Seasonal Changes in the Numbers of Adults in Relation to the Total Population of Prairie Voles.
Throughout the winter of 1945-'46, at Lawrence, the majority of males were fecund; but fecundity in the females was much less, and in January, no females showed signs of reproductive activity. From this it appears that the females, not the males, limit the breeding season of this species.
SUMMARY
In the eleven month period, October, 1945, until August, 1946, in northeastern Kansas, more than five hundred specimens of the prairie vole (Microtus ochrogaster) were examined in the flesh; and forty free-living voles were examined 157 times—an average of slightly less than four times each.
There is a complete molt from juvenal to subadult pelage, and one from subadult to adult pelage. These molts require three weeks each. Subsequent molts are irregular and extend over longer periods of time.
This vole, in summer, inhabits areas of grass, clover, and alfalfa. In winter, habitats with some woody growth may be sought. Twenty-two kinds of plants were found to be used for food. Although most of these were succulent plants, seeds and small woody stems were sometimes eaten. The prairie vole, like some other species of Microtus, lays away stores of food, usually underground; the maximum quantity found in one cache was two gallons.