Big Brown Bat, Eptesicus fuscus. (Angell Williams / Flickr; cc by 2.0)
(© Peyker / Shutterstock)
Colony of hibernating bats being measured for size by USFWS / Wiki (PD) staff.
Winter is hard on Virginia Opossums , as they have a bare tail and toes. (© Sleepy Joe / Shutterstock)
(G. Arriaga, E. Zhou E. Jarvis/Wiki; cc by 2.5)
Young cottontails practicing their courtship ritual. (Porsupah Ree / Flickr; cc by-nc-sa 2.0)