March 2009, Volume 7, Issue 3

Bats in the News

Bats & Wind Energy

The alarming numbers of bat deaths at wind farms have produced an unusual partnership called the Bats and Wind Energy Cooperative. The collaboration of conservation groups, government agencies and the wind industry is seeking a balance between protecting bat populations and meeting the rapidly growing demand for renewable energy, the Chicago Tribune reports.

“We support the development of clean energy, but to make it ‘green’ we have to do everything we can to minimize the environmental impacts,” said Ed Arnett, Co-director of Programs at Bat Conservation International and Project Coordinator for the BCI-led cooperative.

Tribune reporter Gerry Smith wrote that coastlines and mountaintops, which provide some of the best sources of wind, are in the path of migratory bats and birds. That, plus concerns over soil erosions, has led some conservation groups to fight proposed wind farms.
And, Smith reports, “wildlife experts are particularly protective of bats because the mammals have low reproductive rates, meaning even small numbers of fatalities can affect their populations. ‘Once you start taking a small number of bats out of the general population, the risk of endangerment or extinction vastly increases,’ said Joseph Kath, endangered species project manager for the Illinois Department of Natural Resources.
The concern over bats is fairly recent, the Tribune said. Wildlife biologists have been more worried since the 1980s about protecting birds from the spinning turbine, but bat deaths at wind farms largely went unnoticed.
Then in 2003, the newspaper notes, researchers estimated that between 1,400 to 4,000 bats were killed at a West Virginia wind farm and later recorded extensive bat fatalities at wind farms in Pennsylvania and Tennessee.
Until then, Arnett said, “most of us had not anticipated this being a problem.”
Concerns have grown, however, and last summer the American Society of Mammalogists called for wind farms to avoid “bat hibernation, breeding and maternity colonies.”
Meanwhile, the consulting firm Curry & Kerlinger estimated that three times as many bats (93) as birds (31) died during a year at the 33-turbine Crescent Ridge Wind Farm, Smith reported. The firm deemed the findings “small and not likely to be biologically significant.”
But, Smith wrote, given a decline in several bat species in the eastern United States, “the possibility of population effects, especially with increased numbers of turbines, is significant,” according to a National Academy of Sciences study. Illinois is expected to increase the number of wind farms dramatically.
Arnett told the newspaper that the cooperative has been looking for ways to reduce the death toll, including studies of the effectiveness of ultrasonic sounds that would deter bats and of curtailing the spinning of turbines until it’s too windy for bats to fly.
The Tribune quotes Arnett as saying he’s confident the wind industry can continue to grow without harming bat populations. “It’s not choosing one or the other,” he said. “It’s finding a balance. I’m convinced we can solve this problem.”

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