Group uses weather tool to study bats

UVALDE COUNTY, Texas (KXAN) - Meteorologists use Doppler weather radars to detect and track storms, but there's a wealth of data that's cast aside too.

Biological scatter, like migrating birds and feeding bats, also show up on radar but are normally filtered out. Yet, a group of scientists is developing ways to use that information.

“We’re already investing a lot of money in these radars,” said Dr. Phillip Chilson with the University of Oklahoma . “Every radar costs about $10 million. Maintenance for every radar installation is about $500,000 a year, and there’s something like 150 of these scattered across the continental United States. That’s a lot of cash. They’re serving a great benefit from the meteorological perspective, but if you can get value added serving this data out for free to the biological community, then I think that’s a win.”

In late June, the newest rapid-scan, high-resolution, polarimetric, mobile Doppler radar parked eight miles from the mouth of Frio Cave in Uvalde County. It was the mobile radar’s first full deployment.

Instead of tornadic storms, it was tracking the flight patterns of millions of Brazilian free-tailed bats, emerging from Frio Cave at dusk.

"Now, we’re really focusing on taking a census of how many bats we think are coming out of Frio Cave. And if we can do that reliably, we can compare that with NEXRAD, and then a whole new world opens up for us," said Chilson.

Just like a Doppler radar can estimate how much rain is in a rain cloud, the scientists hope to use the same idea to count the number of bats in a bat cloud.

"The farmers in this area, not everyone realizes it, but the bats are their friends,” said Chilson. “The more bats, the healthier the colonies are, the less pesticides they have to use."

The project has no fancy acronym; Chilson calls it "Stone Soup" science, after the children's fable. The funds come from University of Oklahoma's College of Atmospheric and Geographic Sciences . National Science Foundation funded the mobile radar, and the scientists come from across the country and bring their expertise for a common goal.

Dr. Tom Kunz, with Boston University's Bat Lab , is using this thermal imaging camera to count the bats as they fly out into the night. Kunz coined the term "areoecology" as an emerging scientific field. Areoecology is the study of biology in the lower atmosphere, where radar provides a unique view of that environment.

"We’ve always had to be on the forefront of technology to know what’s going on with the bats because bats are difficult to study because they’re flying around at night,” said Dr. Winifred Frick with the University of California, Santa Cruz. “Having a tool like the radar, and different kinds of radar where we can really see the bats and the way they're using the landscape, is pretty phenomenal."