Unfortunately, existing wind turbines have one major flaw. Thousands of birds and bats are killed each year by the rapidly rotating blades. Frequent victims are golden eagles and other birds of prey. Because raptors reproduce slowly, losing a large number of them each year reduces the population and makes the species more vulnerable to other impediments to its survival, such as the loss of habitat caused by development.
The National Audubon Society has been advocating for the replacement of old-style turbines with newer and more powerful models, each of which produces more energy. Fewer turbines will be able to do the work of the current number, thus reducing the number of whirling blades and the consequent danger to birds. Other new, more bird-friendly designs are also in the works.
But the design of wind turbines is only one factor in reducing bird deaths. The other is the location of wind farms. It has been said that Altamont Pass is one of the worst places to locate a wind farm. This is largely due to the plentiful rodents (ground squirrels, especially) that live in the hills and provide a feast for raptors. The mild climate of the area also attracts a large number of migratory birds; in fact it has one of the largest populations of wintering golden eagles in the state.
To help more judiciously locate future wind farms, Audubon has been working with the state and federal government and sharing data about Important Bird Areas (areas recognized as being globally important habitats for the conservation of bird population.) Wind farms located in the west and midwest appear to have lower bird mortality rates, perhaps because they are located away from major flyways. To some extent, the wind industry has cooperated in placing new wind farms in areas where they will have the least possible impact on birds.
No one can dispute the importance of developing more environmentally friendly, renewable energy sources. Wind energy has the ability to reduce our dependence on coal and other fossil fuels, thereby reducing air pollution and even slowing the alarming pace of climate change. And, the number of birds killed by wind turbines is still a fraction of those killed by other causes, such as outdoor housecats
Wind farms are not going to go away, and they shouldn’t. Those of us who love birds, however, hope that continuing research, thoughtful design and careful location will reduce the impact of wind energy on avian life.
WERC is a licensed 501(c)(3) organization that has provided wildlife education and rehabilitation services in the South County for 25 years. Amy Randall Yee has lived in Santa Clara County for 38 years and has volunteered at WERC for eight years. Send her an email at [email protected]