VIDEO: Banding Helps Researchers Study Bats
Recently on KSMU, we told you about how National Weather Service radar helped discover a large summer roosting site for the endangered gray bat in Southwest Missouri. Recently, Michele Skalicky met up with a Missouri State biology professor, his graduate students, a Missouri Conservation Department biologist and two master naturalists as they captured some of the bats in Dallas County and banded them. Here are some sounds from the evening.
A few hours before nightfall on a recent late August day, MSU biology professor, Dr. Lynn Robbins, and four of his graduate students put up mist nets on private property in Dallas County. The nets were originally made to catch birds, but they’re very effective for capturing bats to study them.
Tiny, metal bands, marked with blue glow-in-the-dark paint, sit on a nearby table. They’ll be attached to the bats’ wings so that, when biologists enter caves to look for the bats later, flashlights directed on the bands will make them show up.
"Because a lot of times they're so far up you can see a band, but to get them down and get a number off it and find out where it went--you don't always, you know, do that," he said.
A different color is used for each study location. Why go to all this trouble to capture and band bats? Robbins explains.
"We're trying to, one, document the continued existence of the gray bats here at this wonderful maternity colony and to put bands on a representative of them and see if we can track them later in the winter to where they go for hibernation," he said.
According to Robbins, the research will let biologists know what areas to protect. The federally-endangered gray bat roosts in caves year-round. And protecting them is more important than ever with the potential spread of white nose syndrome—a fungal infection killing bats that hibernate in caves—that has been detected in Missouri.
Robbins says, once caves were protected, the population of gray bats quickly began rebounding, and there was even a good chance they could be taken off the endangered species list. But that was before white nose syndrome appeared and changed that.
The nets are up and ready, and it’s almost time for the bats that are roosting below us to fly out to feed on insects.
"The bats can hardly pick them up with their sonar. You put the nets in places the bats commonly fly, and they're not looking for something in their way, and so they'll hit the net, hopefully, and get tangled," he said.
While we’re waiting, Robbins brings out a device called a bat detector—it renders audible bat sounds that are too high for human ears to detect.
(bat detector sounds)
As darkness fell, swarms of gray bats began their acrobatics in the night sky. And the mist nets began to fill up.
Before long, there were at least 30 bats in one net and a few in the other. The students began to carefully extricate the bats to put into holding containers, and it wasn’t always easy.
The bats made it known that they weren’t too happy to have their foraging temporarily interrupted.
But they would soon be free—flying once again through the night to capture insects using echolocation—a form of radar that allows bats to see what’s in front of them. The mist nets were just fine enough that echolocation didn’t prevent them from getting caught.
Once all the bats in the nets were in the holding containers, the banding began. The tiny bands were attached on the wing to what would correspond to a human wrist, according to grad student Cheyenne Gerdes.
"It's like a tiny bracelet, 'cause their wing is actually made up of their hand, so I put the band on their wrist," she said.
While students did the banding, a master naturalist took down the details.
Headlamps worn by students, allowing them to see what they were doing, attracted a large number of insects. And the students couldn’t avoid ingesting some.
By the time the job was done and all of the bats had flown off to resume their foraging, more than 60 of the flying mammals had been banded.
Biologists now have another tool to use when studying these endangered, beneficial creatures.