When a species is listed as threatened or endangered, the U.S. Fish and Wildlife Service (FWS) then designates the critical habitat to be protected for that species. Critical habitat is the specific areas that contain the features essential to the conservation of the listed species.
In April 2015, the FWS listed the northern long-eared bat as threatened. This was a controversial listing, as the primary threat to the species is white-nose syndrome, a fungal disease affecting many bat species, with little understanding about how to treat or prevent its spread. At the time of the listing, the FWS determined that designating critical habitat was “prudent but not determinable.”
On April 27, 2016, the FWS updated its determination, finding that designating critical habitat for the northern long-eared bat would “not be prudent.” Based on an in-depth analysis of the bat’s seasonal habitat needs, FWS concluded that designating critical habitat could do more harm than good.
FWS noted that the designation of winter critical habitat for the northern long-eared bat (primarily caves and mines) may result in increased disturbance and vandalism of bats due to the identification and related publicity of these critical habitats. Disturbance of this habitat could also increase the spread of white-nose syndrome. Regarding summer, or roosting, critical habitats, FWS found that northern long-eared bats are highly flexible in their summer roosting patterns and use such a wide variety of forest areas that designating critical habitat would not benefit the species.
The Federal Register publication is available here.