Batty: UF builds a third bat house
On Sunday, Dec. 6, 1987, a grease fire leveled the University of Florida’s historic Johnson Hall, which had been home to UF’s first official dining hall, the Rathskeller pub and, less widely known, a colony of 1,000 bats that lived in the attic.
Initially, the bats scattered. At first, no one knew where. But in time, it was discovered that hundreds had nestled into the upper reaches of the tennis stadium, the track venue and even the rafters of Florida Field. Spectators, during games and matches, started to notice the bats and feel droplets of bat guano and urine raining down.
The fans were not at all amused, leaving a difficult problem for the university. Driving bats away from a favored place, especially a high, hard-to-get-to spot like the top of a stadium, is a tricky business: First, they’d have to be removed, carefully — they are protected by Florida law — and then wire mesh would have to be installed to keep them from coming back.
UF’s Division of Environmental Health and Safety, which numbers pest control among its responsibilities, began working to exclude the bats, but the university also tried something else — it built a massive bat house near the edge of Lake Alice. The $25,000 project, which created room for more than 200,000 bats, was paid for by an Athletic Association booster and was finished in 1991.
The bats didn’t take to it right away. Bill Properzio, director of UF’s Division of Environmental Health and Safety, says his workers tried everything. They captured bats and carefully placed them between the bat house’s plywood fins, where the bats could climb in and hang on. The bats would stay for a day, but at night would fly off to feed on insects and wouldn’t return.
In response, workers tried slathering guano on the slats in hopes that the odor would entice the bats to stay. That failed as well.
The workers even piped in recorded bat squeaks, thinking that might be inviting.
“That didn’t do any good, either,” Properzio says. “In retrospect, we didn’t know what the other bats were saying.”
Three years later, a few bats finally started staying. And within a few years, the house was alive with bats. Students and tourists began congregating between the house and the lake to wait for the colony to emerge at dusk and fill the sky with wave after wave of bats.
“We had no idea that the public would be so interested,” Properzio says. “That wasn’t part of the original plan.”
By 2009, the bat house was becoming too popular — not with the people, but with bats. The weight of the tiny mammals and their guano, which had been supported by deteriorating, urine-soaked slats of wood, caused the center section of the house to collapse, killing about 100 bats and making the rest of the structure unsafe for the thousands that stayed.
After making repairs, UF officials decided the bats needed more space and built a second bat house, nicknamed the “bat barn,” next door. Constructed for less than $50,000, the bat barn was designed to allow the guano to fall to the ground rather than build up inside. Together, the two structures have space for more than 700,000 bats.
The bats took to the barn within three or four months. Now about 400,000 bats — who consume an estimated 2.5 billion insects every night — live in the two structures. The colony, consisting of Brazilian free-tailed bats (Tadarida brasiliensis), Southeastern bats (Myotis austroriparius) and evening bats (Nycticeius humeralis), eat “any insect that flies, including mosquitos,” says Paul Ramey, assistant director of marketing and public relations at the Florida Museum of Natural History.
Last year, UF officials decided a third house was needed because of the uncertain future of the original bat house. Although it was repaired in 2009, the original is 26 years old and, as the guano builds up, it’s deteriorating like before. It could fall at any time.
“We don’t want to wait for another collapse before we do something,” Ramey says.
The third bat structure was recently completed at a cost of $90,000. Known as the second bat barn, it essentially replaces the original bat house, which will eventually be removed. The new one is larger than the original and is designed to allow the guano to fall to the ground. It also includes some concrete-fiber siding as part of its construction.
The only question is: Will the bats take to it?
Properzio hopes so.
“We’re not going to play bat sounds this time, and we’re not going to put guano in there,” he says. “We’re just going to sit back and see.”