The U.S. Fish and Wildlife Service said Tuesday that it was launching a 90-day investigation into whether the eastern small-footed bat and the northern long-eared bat need protection under the Endangered Species Act. The two species are the first to be evaluated - and would be the first to be classified as endangered and threatened - because of white-nose syndrome.

Since its discovery in 2006 in the East, the deadly disease - named for the sugary smudges it leaves on noses and wings - has killed more than one million cave-dwelling bats and is moving westward.

State and federal agencies have taken steps to halt its spread, including barring people from caves.