California holds just 22 documented records of the Arizona myotis, every one of them from a museum or agency survey rather than a citizen photograph. That’s a thin file, even by the standards of a small brown bat that spends its days tucked out of sight.
A mountain bat at the far edge of its range
Most of this species’ records come from New Mexico and Colorado, with Arizona and California trailing well behind. California marks the western fringe of a bat built for the southern Rockies and Interior West highlands. Records elsewhere in its range run from foothill country past 9,800 feet, typically around 6,600 feet, the kind of mid-to-high conifer forest, rocky outcrop, and mountain stream corridor found in California’s own Sierra Nevada and Klamath Mountains rather than the low desert floor most people picture in a Southwest bat.
Reports cluster in the warm months, then vanish
Every one of California’s 22 records falls between April and August, with May alone accounting for ten of them. That fits a bat that goes quiet through winter, holed up in a hibernation roost, and becomes active and detectable by echolocation only once nights warm and flying insects return. A record set this small can’t rule out a longer season; it can only show when surveyors happened to find the bat.
Status in California
NatureServe ranks the Arizona myotis S1, critically imperiled, in California, a sharper designation than the bat carries across the core of its range further east. It’s classified as native to the state. With so few confirmed records, the roosts this bat actually depends on here remain largely undocumented.
Full species profile
