White-Nose Syndrome

White-nose syndrome is a strange disease effecting bats from New Hampshire to Tenessee.  Bats are found to have white fungus around the muzzle and other various body parts.  Some tend to have low body fat and many are found to exhibit strange, destructive behavior such as favoring the cold and hunting on cold winter days when their insect prey will not be around, wasting valuable energy.  The fungus is largely unstudied and work is being done to see how the fungus acts and how to stop it.
http://www.fws.gov/whitenosesyndrome/