Nearly all Pennsylvania records for the tricolored bat come from GBIF specimen and survey data rather than iNaturalist sightings, in line with how this bat is actually documented: hibernacula counts and mist-net surveys, not casual photographs of one of the smallest, most erratically flying bats in the country. Reports cluster in late winter through spring and again heavily in November, a pattern that likely tracks when biologists are counting bats at hibernation sites rather than when the bat itself is most active.
NatureServe ranks the species S1, Critically Imperiled, in Pennsylvania and G3, Vulnerable, worldwide, the fallout of white-nose syndrome emptying caves that once held thousands of these bats. What used to be one of the state’s more frequently encountered bats now shows up only occasionally in the record, a shift the numbers make plain even without a population count.
Full species profile
