Great Basin pocket mouse barely registers in Arizona’s occurrence record, with just 40 records statewide and every one of them GBIF specimen or occurrence data rather than an iNaturalist photo. That thinness is exactly what the species’ range predicts: Arizona sits at the extreme southern edge of a range centered hundreds of miles north, in the sagebrush basins of the Great Basin.
A Great Basin animal that barely crosses into Arizona
Mohave and Coconino counties hold every one of the state’s records, concentrated in the Arizona Strip north of the Grand Canyon, the one corner of the state where the sagebrush and shrub-steppe country the species needs actually reaches south of the Utah line. Everywhere else in Arizona, from the Sonoran Desert basins to the Sky Islands, sits outside its known habitat entirely.
A burrow sealed against the desert surface
Like other pocket mice, this species plugs its burrow entrance from the inside during the day, trapping humidity and buffering against surface temperature swings, then forages after dark for the grass and shrub seed it carries home in fur-lined cheek pouches. Arizona’s few records land mostly in summer, consistent with the pattern documented across the rest of its range: activity above ground drops off once the animal seals in for the cooler months.
Status in Arizona
Great Basin pocket mouse is treated as native to its mapped Arizona range and isn’t flagged as nonindigenous by USGS NAS, though it hasn’t received a state conservation rank here. A record this thin at the tail end of a species’ range is the expected pattern, not a sign of scarcity within the range the animal actually occupies.
Full species profile
