Red bats (Lasiurus borealis) are North America's most abundant "tree bats."
In summer they often can be seen catching moths around street lights. Their daytime roosts are in tree foliage, where they hang by only one foot, looking like dead leaves. In fall, they travel south in migratory waves, often with small birds. They overwinter from the Ohio River Valley southward and in mild coastal areas, apparently hibernating in tree hollows.
Red bats are especially well
-adapted for survival during the drastic temperature fluctuations of colder climates. Their long, silky fur provides extra protection from severe cold, and they also use their heavily furred tail membrane like a blanket, wrapping themselves up almost completely. While in hibernation, they respond to subfreezing temperatures by raising their metabolic rate to maintain a body temperature above their critical lower survival limit.
Photo by Merlin D. Tuttle