Wisconsin’s occurrence databases hold 783 groundhog records, concentrated almost entirely in spring and summer, with next to nothing reported between November and January.
Burrows in the Baraboo bluffs and refuge edges
Groundhogs need open ground with enough soil depth or rock cover to dig a burrow system, conditions found in the prairie remnants and oak savanna edges of Devil’s Lake State Park’s quartzite bluffs and in the farmland bordering Horicon and Necedah National Wildlife Refuges. They graze grasses and clover in these open patches rather than the wetlands themselves, digging multi-entrance burrows into the same kind of well-drained slope or field edge wherever it occurs across southern and central Wisconsin.
A true hibernator, not just a quiet season
The near-total absence of winter records lines up with real groundhog biology rather than a lack of searching. Groundhogs are true hibernators, dropping their body temperature and heart rate for months at a stretch inside a den chamber below the frost line, and they don’t resurface until the length of daylight starts pulling them out again in spring, exactly when Wisconsin’s records begin climbing.
Status in Wisconsin
NatureServe ranks the groundhog S5, secure, in Wisconsin, and it’s native to the state. It holds onto open, well-drained ground across the southern two-thirds of Wisconsin, from refuge-edge farmland to the prairie remnants ringing the Baraboo Range.
