The western harvest mouse is one of the easier small rodents to tell apart in hand: it’s the one with a groove running down each upper front tooth, a feature no deer mouse or vole in North Dakota shares. It’s also a committed seed-and-grass eater, weaving small nests low in dense grass rather than digging burrows.
All 518 North Dakota records come from GBIF, with no iNaturalist photographs at all, which lines up with a mouse this small and this well hidden in grass cover. Reports climb through summer and peak hard in August, at 164 for the month, then drop off fast by October, a curve that likely tracks when small-mammal surveys run rather than a true population swing. J. Clark Salyer, Long Lake, and Chase Lake national wildlife refuges, the three named spots in the record, are all wetland-grassland complexes suited to the dense grass cover this species needs.
NatureServe lists the species as globally secure (G5) and native to North Dakota, without a separate state-level rank on file (SNR).
Full species profile
