A new study from Edward Arnett of Bat Conservation International in Austin, Texas and colleagues, recently published at Frontiers in Ecology and the Environment, a journal of the Ecological Society of America, shows that a slight alteration in turbine operation practices can have a big effect in reducing bat fatalities.
Currently, most wind turbines in the U.S. are programmed to “cut in,” or begin rotating and producing power, once wind speed has reached approximately 8 to 9 miles per hour (mph). Researchers found that by raising the cut-in speed just a bit–to roughly 11 mph–bat fatalities were reduced by at least 44 percent, and by as much as 93 percent, with an annual power loss of less than one percent.
“This is the only proven mitigation option to reduce bat kills at this time,” said Arnett, in a statement. “If we want to pursue the benefits associated with wind energy, we need to consider the local ecological impacts that the turbines could cause.” He goes on to note that while he and his colleagues have seen a rise in bat mortality associated with wind energy development, their study shows that a marginal limitation on turbines during the summer and fall months can help to maximize bats’ chances of survival.