Southeastern Big-Eared Bats
Conservancy scientist observes The Disney Wilderness Preserve’s colony in 2010
It’s hard to miss the signs of Halloween in October: Jack-O-Lanterns grin and costume shops magically appear. But all year long, far away from commercial clutter, a rare species of bat haunts the swamps of the Conservancy’s Disney Wilderness Preserve.
The legend of these flying mammals, best known as the southeastern big-eared bat, reads like a real-life Halloween story. It began when an eccentric (some said insane) professor from Transylvania University visited the home of John J. Audubon. While there, Professor Rafinesque captured and documented a new species (destroying Audubon’s violin in the process). Despite the damage Audubon considered his visitor a brilliant naturalist, and the newly discovered creature formally became “Rafinesque’s big-eared bat”.
Years later at The Disney Wilderness Preserve, some no-doubt surprised Conservancy staff made a discovery of their own. Cautiously venturing into a long-abandoned hunting trailer, they came face-to-face with what was thought to be the southernmost breeding colony of the species. (Later sightings confirmed them as far south as Fisheating Creek).
Beginning with UCF graduate student and Conservancy intern Laura Seckbach-Finn’s thesis work, our “trailer bats” have emerged from relative anonymity to become one of the well-studied populations of the species. Still, little is known compared to other plants and animals.
The bats’ preferred habitat, foraging and food habits, and even their lifespan was once unknown, but the Conservancy has shed light on these dwellers of darkness. We now know they were victims of decades-long swamp logging, displaced from their natural roosts in large hollow cypress and tupelo trees, and forced to find shelter wherever they could.
Their search for a new roost apparently led to a derelict trailer, now ready to fall apart with the first stiff wind. The Conservancy has built them a special, cushy substitute – their own little “bat condo” right next door – but so far most of the females have snubbed it.
When they’re not hanging out at the trailer, big-eared bats are known as gleaners. Unlike many bat species that fly in open areas at dusk to feed on insects, these hunt in total darkness. They use their large ears as “radar dishes”. They have a unique ability to move their heads while their ears remain stationary, and can zero in on a moth or grasshopper in the dark or fly through shrubs to pick off prey.
Despite natural talents and adaptability, the southeastern big-eared bat faces modern, man-made challenges. Loss of their swamp forest habitat remains a problem. In addition, their big ears are highly sensitive to disturbance.
Several studies investigated the impact of airboats on the bats. Scientists fitted the bats with tiny transmitters to track their movements. Findings showed they were spooked by airboats along nearby Reedy Creek and would forage miles from their roost. This put them at greater risk of predation and physical stress.
While several years of drought had lowered the creek and kept airboats farther away, recent rains have again allowed the boats to come closer to bat territory. Losing our beneficial bats is a story that should scare us all … at Halloween and all year long!