Houston, Texas, is usually a good place for bats to live, thanks to its generally mild climate. But on the night of December 21, temperatures fell from the 60s to the 20s (degrees Fahrenheit), endangering many of the city’s Chiroptera residents, particularly the Mexican free-tailed bats that roost under Houston’s bridges.
Thanks to the quick thinking and tireless work ethic of Mary Warwick of the Houston Humane Society TWRC Wildlife Center, over 1,500 bats that would have otherwise perished survived last month’s cold snap and have been released back into their natural habitat.
Warwick, the Houston Humane Society’s wildlife director, was running errands on the evening of December 21 when she wondered how the bats roosting under the bridges were doing. She knew that such low temperatures would make it impossible for the tiny creatures to continue clinging to the underside of the metal structures, and was keen to avoid a repeat of last year, when a winter storm led to the deaths of 5,000 bats in Texas.
There were nearly 140 bats on the ground below Waugh Drive Bridge when Warwick arrived, having become hypothermic and fallen. Luckily for them, as a leading wildlife rehabilitator and bat expert, Warwick knew exactly how to help. She gathered the tiny animals into a box in her car and warmed them up using the seat heater. At her home, they were moved to an incubator and given fluids and mealworm gruel. Warwick and her colleagues collected hundreds more bats from Waugh Drive Bridge and Fite Road Bridge, along with many others that had been reported by local residents.
With advice from Bat World Sanctuary and her own in-depth knowledge of bat physiology, Warwick was able to save the vast majority of the bats they collected. One crucial decision was moving the bats to her attic, rather than keeping them in an incubator. The cooler temperatures slowed the bats’ metabolisms so they didn't need constant feeding but still drank water.
A batty home for the holidays:
- Most of the bats were able to be released by December 28, when temperatures rose into the 70s (°F). Sadly, 115 bats died, some of which had likely been injured by the initial fall from the bridge. At one point, the bat population in Warwick’s attic reached 1,602.
- Mexican free-tailed bats are only about three inches long. With minimal body fat, they can quickly become hypothermic.
- Bats in the Houston area play a crucial role in the local ecosystem, keeping populations of mosquitos and other insects under control and helping farmers limit pesticide usage.
