Wind power turbines are killing thousands of birds and bats in Washington and Oregon each year, a series of recent surveys has found.
Wind farm proponents characterize the number of deaths as statistically insignificant and say efforts should continue to expand use of the energy source. Conservationists warn that with so many birds already being killed, bird and bat deaths will rise exponentially if a substantial increase in wind power is implemented to replace conventional power sources.
Thousands Killed Each Year
A recent study in Klickitat County, Washington indicates 6,500 birds and 3,000 bats are killed annually in the two states—though the number of deaths in the two states may be much higher. West, Inc., a company that provides environmental services for both public and private sectors, reports an untold number of birds are devoured by vultures or coyotes before they’re included in the count.
Whether the 10,000 annual bird and bat deaths in the two states are significant depends on who is doing the evaluating.
“Generally, the numbers from the Pacific Northwest are showing a low mortality for birds and bats,” said Clayton Derby, a senior manager at West.
On the other hand, the National Wind Coordinating Collaborative (NWCC), in its latest report on “Wind Turbine Interactions with Birds, Bats, and their Habitats,” concludes turbines pose a hazard for birds and bats, and “fatality rates vary widely regionally across wind resources areas.”
“Most of North America’s birds are songbirds, most of these are migratory, and most of the migratory species migrate during the night at altitudes generally above rotor swept areas when weather conditions are favorable,” the NWCC finds. “Risk may be greatest during take-off and landing where wind facilities abut stopover sites.”
Stimulus Money Funding Turbines
The bird and bat deaths have emerged as a political issue in Klickitat County, Washington, a popular region for wind farms that just received a $200 million federal government stimulus grant to double plant capacity at one of its Windy Flats sites.
A recent study at Klickitat’s Big Horn Wind Farm estimated more than 30 raptors were killed in a one-year period of farm operations—roughly seven times what was estimated by wind farm supporters before the site was constructed. One raptor killed, a ferruginous hawk, is listed as a threatened species in Washington.
Cheryl K. Chumley ([email protected]) writes from Northern Virginia.
Wind Turbine Interactions with Birds, Bats, and their Habitats: A Summary of Research Results and Priority Questions: