Ok, maybe Karaoke is stretching it. But bats do “sing”, sort of.
First, they make plenty of audible chirps and clicks and squawks during the day in the bat house. In fact, we first figured out that we had residents in our backyard bat house when my daughter heard them chirping one afternoon while she was hanging out laundry. Thinking that birds had invaded the bat house that had sat empty the preceding two years, I shined a flashlight up inside, and — Wow — not birds but bats. They’ve been there ever since.
Second, and more famously, bats use bio-sonar to echolocate. Basically they make really loud, very high-pitched sounds, listen for the return echos from objects and potential prey, and then navigate appropriately toward or away from obstacles. These chirps are normally inaudible to humans, since they begin at about 40 Kilohertz (40,000 cycles per second), roughly twice the highest frequency that we can hear. But you can assemble or purchase a simple bat detector that will translate the bat’s echolocation sounds down to the range of our ears.
Here’s an example of what they sound like:
In future posts, we’ll talk about bat detectors and how you can hear and record bats flying through your neighborhood.