These feed on flying insects and avoid predators by hunting just after dusk and sometimes before dawn.
Bats are warm blooded, so prefer warm conditions, and they hibernate when it is cold.
Although their sight is quite good, they use sonar to help them navigate around obstacles and locate their prey in the dark . The bat makes a loud noise, at a pitch above our hearing range. The reflected sound is interpreted by the bat to form a kind of picture of its surroundings. We can transform the sound from the bat to a lower pitch with a bat detector, so that we can hear it. The sound playing now is from a pipistrelle, recorded using a heterodyne detector.