The brown bat is a true hibernator - its body temperature drops and its heart rate slows to conserve energy. Still, the bat may wake up on an average of once every two weeks during hibernation, and may even take flight on a warm winter evening. You can find out more about bats and other nighttime denizens of the woods by taking part in the Museum's Enchanted Forest program on the evenings of October 22 or 23. A bat guides itself through the dark by locating the echo of its own squeaks. This is called echolocation.
Human ears can detect a range of sixteen to thirty thousand vibrations per second.
Bats can hear from thirty thousand to seventy thousand vibrations per second. So, bats broadcast a high vibration of squeaks and detect the interval of time it takes for the echo to return to their ears. As a bat approaches an object the echo returns to its ears more quickly than if the object were farther away. The high frequency of the squeaks paired with the very sensitive auditory system of the bat allows the nocturnal flyer to hunt tiny insects and avoid obstacles with amazing accuracy. In fact they can detect objects as fine as human hair.