The Green Dilemma: Bird casualties from wind turbines

How green are you? You may just want to reduce the carbon emissions through solar and wind power, recycling and not having bonfires in your yard. Or you may be green through to the core and embrace the full panoply of green environmental issues, including the protection/preservation of birds. What happens when green issues conflict?

While the unsightliness and noise of wind turbines may rest in the “nuisance to be tolerated for the greater good” box, where turbine blades have caused bird deaths, particularly of protected species, such as Golden Eagles, committed environmentalists seem to be caught between a rock and a hard place?

In a recent edition of the newspaper “New Mexican”, there was a front-page story about golden eagles apparently falling victim to wind turbines in the Tehachapi Pass of California’s Coast Range in the United States of America (photo below).

California Wind Farm 300x1991 The Green Dilemma: Bird casualties from wind turbines

With over 35,000 turbines in the US, about 440,000 birds are killed at wind farms each year, according to the Fish and Wildlife Service estimates.  However accurate figures are difficult because scavengers will quickly dispose of the bird carcasses. But a number of Golden Eagles having fallen victim to the wind turbines at Tehachapi Pass has raised the temperature of the birds versus wind turbines debate. While it may seem that the bird casualty cost is a high one, let’s not forget that the wind turbine-casualty count is small compared with to those caused by power lines, plate-glass windows, radio towers, airplanes, motor vehicles and even cats.

With the US Government and industry pushing for a 20% wind-power share of energy supply in the next 20 years, there may be a need for some planning and strategic thinking here. The bird casualty count can be reduced by consideration given to the siting and spacing of wind turbines, particularly in relation to established bird migration routes. Could some turbines on a migration route be switched off or mothballed for a few weeks during the main migration period?  The US has no laws on protection of birds from wind turbines. There are Federal rules protecting raptors and migrating birds, but they are optional to wind farmers.

But things seem to be changing, at least in Northern California where there are 4000 wind generators on a major migratory route on Altamont Pass.  The Altamont Pass is a crucial point in the state’s wind-powered energy industry. It’s a narrow cut in the hills between the ocean and central valley, where winds reach high speeds, ideal for wind farming.  Many of the turbines here were established in the 1980s with little or no consideration for bird flight paths and migration routes.  In fact the area has been called a museum of wind power development as new turbines have been added alongside older models. But now, sets of these older wind turbines are being replaced with single massive turbine towers, over 400 feet tall, with slow moving blades and high-gear generators. The wind power lobby says that these changes can reduce avian casualties by as much as 80%. The company responsible for the largest bank of wind turbines at Altamont Pass, NextEra Energy, will also contribute 2.5m$ towards habitat restoration for threatened bird species. Other wind turbines will be placed higher and further apart, while some will be deactivated. Lattices that can attract birds to nest in the turbine tower structure have been removed to discourage nesting in such a dangerous environment. The work is due to be completed by 2015.

Altamont Pass 300x2241 The Green Dilemma: Bird casualties from wind turbines
Older wind turbines at Altamont Pass: These will be replaced…
Birdfriendly Turbines11 The Green Dilemma: Bird casualties from wind turbines
…by new, larger and more efficient bird-friendly turbines.

 

In keeping with recent scientific research on bird habitats, the deal struck requires NextEra to place the modern turbines away from ridge tops and valleys, where many of the eagles, kestrels, falcons and owls ride updrafts or hunt for prey. That provision represents a key victory for wildlife groups that say little thought was given to where the original turbines were erected.

“This is the first chance across the nation to take what was learned about turbines over the last 30 years and put it into use,” said Mark Welther, executive director of the Golden Gate Audubon Society, when the deal was made. “We support wind energy, but we need to make sure we don’t sacrifice birds and wildlife to have renewable power.”

So it seems you can have your green cake and eat it… with a little foresight, planning and consideration, birds and wind turbines can co-exist.