Frank Black Middle School student Andrew Mitchell was riding his bike with friends after the winter storm when he saw a lot of dark splotches along the bayou and the bike path underneath the Watonga Boulevard bridge. He knew that’s where the bats lived.
“At first I thought (they) were sleeping on the ground,” Mitchell said.
When he got closer, Mitchell realized most of the bats were dead.
As with other wildlife in Southeast Texas, the recent freezing weather proved deadly. Along with the Waugh bat colony, the Watonga colony was hard hit by the record low temperatures.
Oak Forest’s Amanda Massingill had avoided the Watonga area for a few days after seeing Buffalo Bayou Partnership's post asking people to stay away from the Waugh bridge.
Massingill went by Feb. 24 and saw bats on the ground. She guessed there were about 100 dead bats as well as some that were alive.
“I notified Texas Parks and Wildlife, which is what Buffalo Bayou said to do if we found downed bats,” Massingill said. “I also commented about checking on the Watonga Bridge bats on every (Facebook and Instagram post) Buffalo Bayou made as well.”
Wildlife biologist Diana Foss with Texas Parks and Wildlife said removal of the dead bats was done by the entity that manages each bridge.
“We have a bunch of bridges with bats, all managed by different groups,” Foss said. “In the case of Waugh bridge, the path underneath is maintained by Buffalo Bayou Partnership. In the case of Watonga bat colony, the dead bats were removed by Houston Parks Board.”
Houston Parks Board President and CEO Beth White said the organization found about 1,000 bats down in Houston after the freeze.
“Of those, about 75 survived and were relocated to recuperate on nearby trees as to remove them from any danger on the trail,” White said. “Houston Parks Board is appreciative of the Bayou Greenway Trail users who have expressed care and concern for the bats. They are such an important part of our ecosystem and we are grateful of the support for our work to steward these important corridors for wildlife and people.”
Foss said some bats were also taken to wildlife rehabilitators.
“Austin Bat Refuge took in huge numbers of bats from the central part of the state,” she said. “Those bats will be released back into the wild when they recover.”
While the freeze was deadly for many bats, the majority of the colony survived, according to Foss. While some Mexican free-tailed bats come to this area for the normally mild winters, most of the Texas and North American population migrate south to Mexico and Central/South America for the winter. So they weren’t here.
Those that were had some degree of protection.
“During the summer months, the bats eat tons of insects and convert that food into body fat,” Foss said. “The stored body fat helps them survive the winter here. During cold temperatures, below 50 degrees Fahrenheit, the bats move into the tightest crevices in the bridge colony and go into a state called ‘torpor.’ It’s like a temporary hibernation.”
Foss said this allows a bat to lower its body temperature, respiration and metabolism – and live off the stored body fat for energy. When the weather warms up, the bat then wakes up and flies out to get water and catch insects again.
“The end of February is typically the end of our cold winter weather,” Foss said. “This freeze created extremely low temperatures for an extended period of time. The bats were near the end of the fat reserves. Some bats just became extremely cold – too cold to survive. Others starved or were very dehydrated, which resulted in their deaths.”
Foss said the bats that made it through will carry on as usual, although it may take a year or two for each bat colony to recover. It all depends on the number of bats impacted by the cold.
“Each Mexican free-tailed bat female gives birth to one pup per year - in the summer,” Foss said. “If that pup survives, it will help repopulate the colony.”
Foss said the larger part of the colony will return to Watonga starting in March and April.
Texas Parks and Wildlife and the Houston Bat Team also expressed gratitude for the public’s support and concern.
“The bats eat tons of insects every night over our skies – our nightly pest control,” Foss said. “They save Texas farmers up to $1 million annually because the bats are eating the corn and cotton insect pests, so farmers don’t have to apply more insecticides to crops.”
While Foss extols the virtues of bats, she also cautions the public against handling one.
“Please never pick up a bat on the ground,” she said.