Caving experiences, coupled with summer internship, help fuel bat research
There’s one thing that Julia Yearout wants you to know about bats: They’re not scary.
“People think of bats and they think about the Hollywood images of bats sucking your blood. I mean, blood-sucking bats do exist, but they’re not a big threat to us,” said Yearout, a third-year wildlife sciences major in the University of Georgia Warnell School of Forestry and Natural Resources. Her experiences caving in Northwest Georgia and, more recently as a summer bat technician with the Georgia Department of Natural Resources, have brought her up close and personal with the tiny winged creatures.
“The most important thing I want people to know about bats is they’re really great for the environment,” she added. “I’m really thankful for their use of the ecosystem—and, they’re really cute.”
Yearout spent this past summer hanging specially outfitted microphones in trees and slowly driving country roads throughout Georgia as part of a summer internship with Georgia DNR. Summer is maternity season for bats, which means they are often on the move, sometimes with babies in tow, and it’s a good time to count them.
The surveys are important because a disease called white nose syndrome is devastating Georgia’s bat population. The annual survey is organized by the North American Bat Monitoring Program and implemented through Georgia DNR. It aims to keep track of bat colonies and understand how the bats are faring.
White nose syndrome causes a white fungus to grow on bats’ skin while they are hibernating. It itches, rousing the bats from hibernation to scratch. Over time and repeated scratching, they use up their fat stores before the end of winter and starve to death before spring arrives. Yearout first learned about white nose syndrome when she did a 4-H presentation on it as a sixth grader, but at the time she had no idea this initial research would unfold into a potential career path.
“I remember giving the presentation and at the time it hadn’t come to Georgia yet, and since then we’ve seen 98% loss in colonies,” she said. “In the places where I grew up in North Georgia, I’d go in all these caves and see all these bats, and then, through my high school years, just seeing the decline.”
The summer internship to survey bats took her and a partner all across the state—eight different locations for a week at a time—to do nighttime surveys. The two interns would have pre-set locations where they would mount recording devices in trees, in the same places as previous years, and take in the high-pitched bat calls as they fly in the dark.
“It has a microphone on it, and you set it out on a Monday,” said Yearout. “It collects four consecutive nights of data, and it will take data from sundown to sunrise. It will collect any calls that it hears.”
The team would also drive routes with a microphone outside the car to catch bat noises along a set path. That process was a little trickier because the microphone also picked up brake squeaks from other cars, road noise or cicadas. “A mobile route is pre-established, run every year, and is between 15 and 30 miles. You have to run it at 20 m.p.h.—any slower and you could catch the same bat noises because they like to follow the cars and catch the bugs,” she added.
Their drives included South Georgia swamps, Ocmulgee National Park near Macon and even Cumberland Island. Routes could be on dirt roads but most often they stuck to 2-lane country roads.
The recordings Yearout and her partner gathered are converted, via their frequency, into small dots on a grid. By looking at the dots, they can determine the species of bat. When they weren’t on location, they were analyzing data—a process that continues into the fall.
Yearout said she didn’t necessarily plan to study bats once she got to college. But the creatures have always had a presence in her life.
“I came (to Warnell) thinking I wanted to work for the National Parks Service, which I do, but I thought caving was just a phase—my hobby,” she said. “But after this summer, I’ve realized I really like bat conservation and it’s something really close to home for me.”
When she was 7 or 8, Yearout remembers going to Pettyjohns Cave with her father. The cave is a popular destination in Northwest Georgia, with so many people going in and out of its one entrance that it’s been worn to something resembling a slide. “We go in and I looked up at the big room for the first time and I was like, ‘This is so cool.’ And that was the first time I saw a cave.”
Her father, a firefighter, began learning about cave rescue techniques; he is now a national instructor on the topic. Along the way, Yearout explored the caves with him and developed her expertise in climbing and rappelling. She began “vertical caving,” or dropping into vertical cave openings, when she was 14 and experienced her first 160-foot drop. Her biggest drop was 300 feet straight down into a secret cave in Hamilton County.
In high school, she landed a job with a local company and began leading cave tours. That job, and the experience of leading others to explore nature, was what led her to Warnell and the University of Georgia.
“That is where I really found my love for environmental education, by teaching people about something that they were so scared about,” she said. “When you think of caves you might think about queasy crawls, but the you get in and you see these beautiful formations and you just fall in love with it.”
She hopes to pass on that same love for the creatures who inhabit the caves—as well as trees, leaf piles, bat houses and, sometimes, attics of houses.
“Yes, bats can carry rabies—less than 1% of them do; you should be cautious of them,” she said, adding that Georgia DNR can help homeowners remove bats from their houses.
With the exception of maternity season—because of a risk of separating bat pups from their mothers—homeowners can wait until the evening, after bats have left the house, and then put up a screen to prevent bats from coming back in.
But, if you do this at the same time as installing a bat house outside, you will give them a new place to live.
“They can relocate and then you can keep your bats around and they can be your pest control,” added Yearout. “If you’re sitting there at night and there are a ton of mosquitos around, know that the bats are taking care of that. Without bats, there would be tons more than what you see now.”