Count the bats -- how do your skills compare to a bat biologist's?

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Detailed Description

Do you have what it takes to be a bat biologist? USGS bat researchers are counting Townsend’s big eared bats to monitor how their populations are doing. Watch the video to try your hand at a bat count and see how your skills compare to a USGS scientist! You don’t need sound to count the bats—but if you turn your sound on you’ll be able to hear the bats’ echolocation calls while you count! The calls, which sound like clicks, were picked up by an ultrasonic microphone near the roost.


Date Taken:

Length: 00:02:11

Location Taken: Point Reyes National Seashore, CA, US

Video Credits

Text & video editing by Allie Weill, Outreach Coordinator,

Bat photo is from Bureau of Land Management (public domain)


USGS scientists are studying Townsend's big eared bats at Point Reyes National Lakeshore
Bat biologists estimate the bat population in the roost by counting all of the bats as they leave the roost in the evening
To estimate the total, USGS bat biologists use the formula "number leaving minus number entering equals total number of bats"
How do your bat counting skills stack up to a bat biologist's?
This slot is the entrance to a bat roost in an old house
Count the bats that fly out of the slot. If a bat flies into the slot, subtract it from your count.
Get ready to count!
How many bats did you count?
USGS bat biologist Gabe Reyes counted 27 bats in this clip!
This clip shows just 1 minute of a 90 minute bat count, during which biologist Gabe Reyes counted 503 bats!
The bat counts will allow USGS and partners to monitor the status of Townsend's big eared bat in California.