Monday, July 30, 2007

Bat songs

Want to hear a bat singing? I've loaded a few call files on my server for your listening pleasure. These songs are time-expanded recordings slowed down so that they're audible to human ears. If you listen closely, you can hear multiple bats in each short recording. Sometimes there are bats with louder, lower calls, and other times higher, shorter calls. You can also hear clues to how the bats hunt. At first, their calls are regularly spaced. This is called the "search phase", where the bats are just putting out sound in case there's an echo off something to eat (or something to avoid flying into.) Then once the bat finds something, the calls come faster, eventually turning into a rapid set of pulses called a "feeding buzz". Several of these files include feeding buzzes. All of these bats were recorded in April of this year at Jewel Lake in Tilden Park, Berkeley, California. bat call 1 (mp3) bat call 2 (mp3) bat call 3 (mp3) bat call 4 (mp3) bat call 5 (mp3)