Wind turbines kill birds. In fact, the argument that turbines kill a lot of birds has been used to challenge proposed wind turbine developments by neighbouring communities. However, this argument may be off course since, when sited correctly, wind turbines appear to have relatively little impact on birds.
[...] To help put the overall issue into perspective, one American study estimated that an average of 2.19 birds are killed annually at each wind turbine in the United States. Outside of California, the estimated fatality rate drops to 1.83 (there is no published study of the impacts of wind turbines on birds in Canada). Therefore, based on 15,000 American wind turbines in operation, approximately 33,000 birds are killed each year by wind turbines in the U.S., 26,600 in California alone. Although 33,000 is a lot of dead birds, the overall impact is small when compared with the millions of birds that travel over windfarms each year, not to mention the millions to hundreds of millions of birds that die due to collision with transmission lines, vehicles, buildings, and communication towers each year. Even if there were a million turbines in North America, they would likely not contribute more than a few percent of all bird collision deaths attributable to human structures.