Home Range of Microtus Ochrogaster as Determined by a Modified Minimum Area Method

Home ranges of six Microtus ochrogaster were determined by radioisotopic tagging. A modified minimum area method, of delineating home range was derived, using one-fourth of the range length as a standard to determine whether outside points in the range were to be connected directly. Home ranges as determined by the new method varied from 0.05 to 0.18 (averaging 0.11) acres for five males. A single female had a range of 0.02 acres. These figures are on the order of 50% of the range size determined by the minimum area method. Overlapping of home ranges occurs, and one individual showing a marked shift in home range was observed.