A Texas wildlife rehabilitator nursed over 1,600 frozen bats back to health in her attic after many of them fell from their roosts during Houston’s plunging temperatures last week.
Mary Warwick, the wildlife director at the Houston Humane Society, told CNN that she has been working with bats since 2019, when another cold snap sent Houston’s bats falling from their roosts. But she had never staged a rescue operation quite this large before.
On December 21, temperatures in Houston dropped from the 60s during the day to 22 degrees at night. “That’s a steep drop in temperature for the bats,” Warwick explained. The Houston area is home to eight species of bats, including the tiny Mexican free-tailed bats that roost underneath several bridges in the city.
“As their body temperature dropped, they were no longer able to hold on inside the cavity of the bridge,” Warwick said. “Some of them started to become so hypothermic they lost their footing and dropped.”
Warwick was running errands when she realized she hadn’t received any calls about bats needing help, which was unusual given the cold weather. She headed to one of Houston’s bridges “and saw little dots on the ground,” she said.
“There were about 138 bats that had become hypothermic,” she went on. “They looked dead.”
She went to work collecting the tiny bats in a box in her car, where she used the seat heater to start warming them up. “I live about 40 minutes from the bridge, and by 20 minutes, they were starting to move around, which gave me a lot of hope,” she said.
Warwick returned that night to pick up another 50 frozen bats. Then she received a call from someone who had found 920 more bats in need of help.
At her home, Warwick sorted through the bats to determine which were still alive and which had died, from either the cold or the fall to the ground. She put them in incubators to raise their body temperatures and then administered subcutaneous fluids.
But caring for over 1,000 bats was overwhelming. So she reached out to Bat World Sanctuary, a nonprofit based in northern Texas. Bat World was unable to accommodate such a large contingent of bats, but they helped Warwick come up with a battle plan to care for the frozen creatures.
“We decided once I got them stabilized I could put them in my attic where it’s cool but it’s not freezing, and that would reduce their metabolism so they wouldn’t need to eat, but they would drink water,” she explained.
So Warwick divided the bats, using crates to keep each colony together, and left them in her attic to rest and regain their strength. Several other local citizens also called in bats that needed rescuing, bringing the total to 1,602 recuperating bats in Warwick’s makeshift bat hospital. They spent around three days total in her attic, she said.
Only 115 bats collected died, according to Warwick. “I was very happy with that,” she said. “Especially the initial fall – that’s gotta be a hard fall, falling 20 feet from the bridge. It’s remarkable that these little guys can make it through.”
And on Wednesday, with temperatures in Houston stabilizing, most of the bats were released back to the bridges where they came from. A few still struggled to fly correctly and were returned to the attic, where Warwick said they’ll receive “extra supportive care.”
Warwick and other helpers from the humane society rented a scissor lift to bring the bats as close as possible to their roosting area under the bridge. “We wanted bats to have the best chance of hearing and seeing, getting motivated by their friends,” she explained. “They’re very social, they do actually have friends up there, they know their chirps.”
Warwick said that she enjoys caring for bats partially because “they’re so small and tiny, and sweet.”
Warwick and other rehabilitators that work with bats are vaccinated against rabies so they can safely work with the animals, she explained. The Houston Humane Society recommends that people trying to rescue bats either wear thick leather gloves or avoid touching them at all.
Bats are a crucial element in Houston’s ecosystem, Warwick added. They feed on mosquitoes and insects that eat crops, and also act as an important food source for hawks and other predators.
The Houston Humane Society is currently fundraising for a new facility that will include a dedicated bat room, she said.
“We’ve moved into their territory, where they live,” she said. “It’s important for us to take care of them.”