Illinois records for the silver-haired bat cluster along the Des Plaines River corridor, Cook County’s forest preserves, and Midewin National Tallgrass Prairie, places where mature trees meet water or open ground. That’s the kind of edge habitat this frosted, dark-furred bat favors for roosting under loose bark and hunting moths and beetles at dusk.
The 287 records logged since 2000 climb twice a year, once in May and again through September and October. That pattern likely tracks migration more than a summer population settling in, since silver-haired bats are among the more mobile tree bats in North America and Illinois sits along part of that route.
Illinois lists the species as native, and its global outlook is secure. But NatureServe ranks it S3, Vulnerable, within the state, a distinction worth noting even for an animal that isn’t globally at risk.
Full species profile
