Pennsylvania’s occurrence databases hold 615 white-footed mouse records, split between iNaturalist and GBIF. The count reflects documentation effort, not the number of mice in the state, but it does trace a clear pattern: records cluster in mixed farmland-and-woodlot country, not the state’s unbroken forest blocks.
Piedmont edges, not the deep woods
The two places named most often in Pennsylvania’s records, Gettysburg National Military Park and Valley Forge National Historical Park, both sit in the southeastern Piedmont, a landscape of rolling farm fields cut by hedgerows, stone walls, and strips of second-growth woods. That fits the species well. White-footed mice favor brushy edges, fencerows, and patchy woodlots over the interior of a large closed-canopy forest, and the Piedmont’s farm-and-woodlot mosaic gives them exactly that structure across a wide stretch of the southeast.
A nest in the wall, a diet of acorns
Peromyscus leucopus dens in tree cavities, brush piles, stumps, and gaps in loose stone, so the fieldstone walls lining so many old Piedmont farms double as ready-made shelter. It forages at night on seeds, nuts, and insects, and acorns from Pennsylvania’s oak-hickory woodlots make up a large share of its diet come fall. Records climb again in October, a pattern that lines up with the acorn crop and with young mice dispersing to find their own territory before winter sets in.
Status in Pennsylvania
NatureServe ranks the white-footed mouse S5, secure, and USGS NAS doesn’t list it as nonindigenous, so it’s treated as native across its mapped Pennsylvania range. It’s among the most frequently recorded small mammals in the state’s occurrence data, tracking closely with the farmland-edge habitat that covers so much of Pennsylvania outside the big forest blocks.
Full species profile
