Small Rodents as Consumers of Pine Seed in East Texas Uplands

Abstract

Abstract In five years of trapping on forested and open upland in east Texas, rodent populations—mostly mice—varied from near zero to 2.5 and 4.0 individuals per acre. Fluctuations were greater on open than on forest land. Populations usually peaked in winter, when loblolly and shortleaf pine seeds are normally exposed to predation. Home ranges of resident mice averaged about 1.25 acres, but the frequency of transients indicated considerable mobility. Live trapping for three successive nights did not adequately sample the populations, but either seven- or ten-night periods trapped essentially all residents. Caged mice preferred pine to other native seeds; individuals consumed about 1 gram of pine seed daily when confined to this diet, 0.8 gram when offered a choice. Winter populations of 2-4 mice per acre could consume most of the 0.5 to 1 pound of seed normally direct-seeded, but would have little effect on natural regeneration in good seed years, when 15 to 20 pounds per acre may be available. Predation by three mouse species could be differentiated by characteristic evidence on opened seedcoats.