This mouse spends most of the year hibernating underground on stored body fat and only shows itself during a short warm-season window, which shapes everything about how it turns up in Idaho’s records. It needs cool, damp mountain meadows and stream edges, not the dry basins that dominate much of the state, so its 543 Idaho records, all logged through GBIF rather than iNaturalist, cluster wherever willow-lined drainages and wet meadow pockets hold on through summer.
The seasonal pattern is dramatic: 234 records in July alone, June and August also strong, and nothing at all from October through April. That’s less survey bias than biology. This species is essentially invisible outside its brief active season.
Craters of the Moon National Monument and the Morley Nelson Snake River Birds of Prey area both sit along the Snake River Plain, where streams and wetter pockets cut through otherwise arid ground, giving this species the damp corridors it needs even in dry country.
Full species profile
