From KERA News:
Texas may be known for oil, but it is also the nation’s largest producer of wind energy. And while renewable energy is generally a good thing to most people, it’s not great for bats. Those towering wind turbines that harness the wind’s power kill a lot of bats every year.
When you drive by a wind farm out in the countryside, populated with soaring white turbines, their blades slowly spinning, it’s a bit of an illusion. Texas Christian University biologist Amanda Hale says those blades may look like they’re lazily twirling along, but the tip of a 120-foot blade is moving fast, creating a kill zone.
“Those blade tips, at wind speeds at which bats will be flying, are well over 150 to 200 miles an hour,” says Hale, who is leading a team trying to find ways to keep bats from being killed by turbines. “And so as they’re echo-locating and they’re flying, there’s nothing there. And then bam, the blade comes and kills them.”
Now, bats may give you the creeps. The winged mammals have gotten a bad wrap — Dracula and all that – but Hale says they play a big role in the eco system. For one, the same agricultural pests that farmers battle are dinner for bats.
“They also are good at keeping down mosquito populations and so having bats in our communities is probably a really good thing,” she says.
Exactly how many flying bats fall victim to wind turbines is a mystery, Hale says. Maybe a half million every year in the US. Maybe more. Researchers just don’t know, but more wind turbines are built every year and so the risk is growing.
“I think the consensus is that we know it’s a problem, but we don’t know how much of a problem, and that’s why there’s such a push right now for technologies to reduce fatalities while we figure out how many bats there are,” Hale says.
To create those technologies, though, you have to understand why bats are drawn to turbines, and migratory bats are notoriously hard to study. One theory is that they think they’re trees. Another idea: The light colored surfaces attract bugs, which makes wind farms attractive to hungry bats. Hale’s intervention comes from watching the way bats interact with the turbines’. Essentially, she thinks bats are confusing the smooth surface of the turbine for water.