Oklahoma’s Colorado chipmunk lives up to its name: all twelve state records come from Cimarron County, the far western Panhandle, where Oklahoma finally picks up some altitude. This is Black Mesa country, mesa tops and canyon slopes of juniper and oak brush, and it’s the easternmost outpost of a chipmunk that belongs to the southern Rockies. Nearly all the reports come from a single managed tract, which suggests one well-worked site rather than a county-wide spread.
May carries the most records, with July adding a few. Spring emergence after winter puts chipmunks out in force, and young of the year start showing by midsummer, so the calendar fits an ordinary chipmunk rhythm in a place where people are actually watching. The newest report, from July 2025, confirms the colony is still holding.
NatureServe ranks the species imperiled in Oklahoma, though it’s secure across its full range. Both statements are fair. The Black Mesa outpost is tiny, isolated from the main range by miles of unsuitable plains, and exactly the kind of relict population a hot, dry decade could squeeze. For Oklahoma, this little chipmunk is a piece of the Rocky Mountains that ended up on the wrong side of the state line, and it’s worth keeping.




