This is what I like to

American 60 Second Science.

I'm Christopher Intagliata.

Got a minute?

What you're listening to is what I like to call the beautiful chaos of the bat echolocation

streams.

Laura Clepper, a bioacustician at St Mary's College in Indiana.

So you're listening to the sounds of probably a couple hundred bats emerging per second

from the cave, and there's a microphone that we have suspended in the middle of the bats to record the sounds.

These are the echolocation sounds that the bats make when they're flying and this is what they use to help navigate and find prey.

The sounds, which are slowed down 10 times so we can hear them, were recorded at a network of

lava tube caves in New Mexico.

Clepper and her colleagues had camped out there to study how Mexican free-tailed bats echo locate in huge swarms without jamming each other's signals.

And they noticed that the intensity of the bleeps seemed to correlate with the number of bats fluttering out of the cave. the we were sitting around the campfire at our field site and we said you know I wonder I wonder if I

wonder if this would actually work. So they set up a new experiment capturing audio

and GoPro video at the cave site. They counted the bats in each video frame and

correlated that to the zips and zaps to create predictive models. They then tried the

method at another cave and found that their models could indeed estimate

the number of bats emerging using acoustics alone.

The study is in the journal Royal Society Open Science.

Historically, what has been used to estimate bats has been photographic estimates, visual

estimates, mark recapture estimates, and those have been highly prone to bias.

...