Power-generating wind turbines have long been recognized as a potential hazard for birds. But at most wind facilities, bats actually die in much greater numbers.
"Because bats can detect objects with echolocation, they seldom collide with man-made structures," said Erin Baerwald of the University of Calgary in Canada. "An atmospheric-pressure drop at wind-turbine blades is an undetectable—and potentially unforeseeable—hazard for bats, thus partially explaining the large number of bat fatalities..."
Read the article "Barotrauma is a significant cause of bat fatalities at wind turbines" in Current Biology.