Structure of Two Peromyscus polionotus Populations in Old-Field Ecosystems at the AEC Savannah River Plant

Abstract

Field work to determine structure of and spacing within 2 Peromyscus polionotus populations was done on 2 live-trapping grids in 2 fields of different soil types and vegetational covers in the upper coastal plain in South Carolina. No statistically significant differences were found between the sizes of home ranges for adult male and for adult female mice in any season, nor in different seasons in the same field and year. The estimated mean home range for adult P. polionotus in the study was 0.34 ± 0.02 acre, sd 0.17. Mouse populations on the 2 grids were similar in the first year and in comparable seasons in the field retaining a population in the second year of study. The annual population cycle showed a continuous decline from a spring high (April–May) to a midwinter low (Jan.–Feb.), then an increase to the next spring high. Analysis of spacing showed that mice of the same sex were distributed at random and that distances between members of the same sex tended to vary inversely with population density. Distances between members of the opposite sexes tended to remain relatively constant regardless of changes in density.