Another reason for bats to like Halloween

October 14, 2008

bat1.JPGHalloween is just around the corner, and it may be better than most years for one of Earth’s most unpopular species: the bat. 

Something sinister is happening to bats in the United States — not only are their numbers declining due to a mysterious malady, but large numbers of them are also being caught mid-flight in the spinning wind turbines that are cropping up rapidly across the nation.

The furry flying critters may get help this month thanks to an unlikely group of conservationists, wind energy companies and the U.S. government, who say they are undertaking a big effort to lower the number of bats killed by wind turbine blades.

The group, called the Bats and Wind Energy Cooperative, is studying whether stopping wind turbines during low wind conditions will reduce bat deaths at U.S. wind farms. It is also evaluating how much electricity is lost by the shutdowns.

The effort to curb bat fatalities at U.S. wind farms comes as wind power is expanding and North American bat populations are in decline due to a mysterious illness known as White-nose Syndrome

Conservationists have long worried about the danger of birds colliding with wind turbines, though some studies have shown that the number of birds that die from hitting turbine blades is low compared with kills from vehicles or buildings.  The bat study “represents a new area of investigation for the wind industry,” according to Andrew Linehan of Iberdrola Renewables, which offered its Casselman Wind Power Project site in Pennsylvania for the experiment.

According to the BWEC, bat fatalities occur mainly on nights when the wind is scarce and turbines are operating at low power. Scientists believe, therefore, that shutting down the turbines when there is little wind could significantly reduce bat deaths with only a modest reduction in power production.

The group also said that though bats are “often ignored and falsley besmirched,” windenergy1.JPGthey “are vital to the health of the environment” because they are pollinators and seed dispersers in addition to predators of agricultural pests.

The BWEC was formed in 2004 by Bat Conservation International, the American Wind Energy Association, the U.S. Fish and Wildlife Service, and the U.S. Department of Energy’s National Renewable Energy Laboratory.


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Why not generate a signal similar to that emitted by bats and “channel” the bats through a virtual safe corridor between the wind turbines.

The signal will make the bats “see” the wind turbines as walls, and they will attempt to fly higher, or toward a virtual opening. Therefore not having to shut down the turbines.

Posted by Edwin J. Arroyo | Report as abusive

bats are SO important, i’m thrilled to see this article published. a large colony of bats can eat literally tons of bugs and mosquitoes every night. with the huge problems of pesticide application in agriculture, we should be doing everything we can to help bat populations rebound!

Posted by Yusha | Report as abusive

Why can’t an ultrasonic pulse be installed on the windmills? Wouldn’t it be like a beacon to the bats?

Posted by Connie | Report as abusive

I wonder if anyone has done any tests to determine whether vertical wind turbines are as dangerous to bats as the much more common horizontal ones. Also, the previously suggested idea about adding ultrasonic transmitters to the blades is a good one and should be tried.

Posted by Chris | Report as abusive