New Jersey’s little brown bat record is really a Morris County record: 67 of 78 reports come from that one county in the state’s northwest, with Warren, Sussex, and Somerset contributing a few more. That doesn’t make Morris County the bat’s stronghold so much as its best-watched corner, since a cluster that tight almost always traces a survey effort.
The calendar is telling. May leads the year, when bats leave hibernation and maternity colonies form, but November and December together contribute a heavy second wave, the mark of winter checks at hibernation sites. The Highlands’ old mine country, including places like Wildcat Ridge, fits that pattern well.
NatureServe ranks the species S1, critically imperiled, in New Jersey, and the IUCN lists it as Endangered globally. White-nose syndrome hit the state’s cave and mine bats hard, and the little brown bat, once the default bat over suburban ponds, is now one of the most closely watched mammals in New Jersey.
Full species profile
