It's a mistake to think that all of our fall migrants travel south. A few species move in other directions. The Gray Bat is one such contrarian.
Rather than seek out warmth, the Gray Bat prefers a nice chill for the winter and will leave its comfortable summer cave for one with a temperature closer to freezing. Sometimes that means saying good-bye to balmy Florida and flying to cooler Alabama or Tennessee.
The reason for the strange migration is that the Gray Bat hibernates during the winter, and it can do so effectively only in a chilly cave. Its heart rate plummets from several hundred beats per minute to twenty or thirty, and its body temperature takes a similar nosedive. Stored fat sustains the bat until spring, and when it's thirsty, it simply licks some of moisture off the cave walls or some of the condensation off its fur.
Click here to learn more about the Gray Bat.