Nearly all of South Dakota’s fringed myotis records come from one island of habitat: the Black Hills. Custer and Pennington counties hold 28 of the state’s 34 reports, with Jewel Cave, Wind Cave, Badlands, and the Black Hills National Forest each contributing. East or west of the hills, the record nearly vanishes.
That geography makes sense for a bat of ponderosa forest and rocky canyon country. The Black Hills rise out of the plains as the easternmost real mountains on the species’ range, close enough to its western core to hold a persisting population. The caves help twice over: they’re roosting habitat, and they’re where biologists actually look, so some of the cluster reflects effort as well as animal.
Reports peak in June and July, maternity season, when females gather in warm roosts to raise their single pup and surveys catch bats at their most concentrated. NatureServe ranks the fringed myotis Imperiled (S2) in South Dakota, an honest grade for a bat at the edge of its range and tied to a single landform. Protecting roosting habitat in the hills does more for this species in the state than anything happening out on the surrounding plains.
Full species profile
