Newsroom Midwest Region

New technology helps count hibernating bats

October 25, 2017

Service biologist Shauna Marquardt tests new technology to count hibernating bats. Photo by USFWS.
Service biologist Shauna Marquardt tests new technology to count hibernating bats. Photo by USFWS.

It’s a challenge – counting bats during hibernation when they’re sensitive to disturbance. Every two years, scientists head into caves, mines and other hibernation sites to count endangered Indiana bats with as little intrusion as possible. Hibernation sites are dark, and bats are too – adding to the challenge. Surveyors quickly take photos of clusters of hibernating bats and then examine the photos later, counting bat noses to determine population numbers.  But the process is time-consuming and requires teams of surveyors using flash photography. Some new technology may make this biannual effort a little easier.

U.S. Fish and Wildlife Service biologists are trying out a new ground-based scanning system called LiDAR. The technology is used to scan hibernation sites while bats are present, and then again when they’re absent. LiDAR determines the difference in volume between the two scans. The difference represents the volume and number of hibernating bats.

LiDAR operates by scanning three-dimensional point clouds. While it’s necessary to enter hibernation sites to set up and conduct LiDAR scans, the disturbance is minimal and the scans produce high-resolution images of habitat and of roosting bats. LiDAR also provides three-dimensional models of entire caves or caves passages.

It is hoped that further testing of LiDAR will lead to a more streamlined – and accurate – way to count bat noses.