National Geographic : 2010 Dec
seems to be new to North America. Its presence was rst documented--- but not yet recognized---in a photograph taken in February 2006 at Howes Cave, west of Al- bany, New York. A year later, people began to report something peculiar: little brown bats ying outside nearby caves during daylight in the midst of winter. A little brown bat is a tiny creature, smaller than a human thumb, and de- pendent on its two grams of stored fat to keep it alive through the cold season. Hibernation is essential to making its energy resources last; GRIM EVIDENCE Greg Turner, of the Pennsylvania Game Commission, and DeeAnn Reeder (at le ), a biology professor at Bucknell University, nd a fetid mulch of dead bats outside a coal mine in eastern Pennsylvania. "I'm not a sky is falling person," Reeder says. "But for North American bats, the sky is falling."