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Wind power turbines, some people say, pose a threat
to birds, including migrating flocks. If this is true, what is being done
about this?
It is ironic that nonpolluting, renewable wind energy,
long touted as a potential savior in the fight to stop global warming, is
getting a bad rap for killing wildlife. High-profile examples such as
California’s Altamont Pass — where outdated, oversize wind
turbines kill some 1,000 birds of prey each year — plague the growing
wind-power industry, even though more modern, better-sited wind farms kill
far fewer birds. According to a 2002 study of anthropogenic
(human-caused) bird mortality conducted by researcher Wallace Erickson,
birds face daily threats far more lethal than wind turbines.
Erickson’s study found that between 500 million and 1 billion birds
are killed annually in the United States alone when they strike manmade
structures, including communications towers, buildings and windows, and
power lines. Hunting, cat predation, pesticides, commercial fishing
operations, oils spills, and cars and trucks also take a heavy toll. All of
this should be remembered, say wind-power advocates, when the relative
impact of windmills on bird populations is put in perspective: Contact with
wind turbines represented less that 1 percent of the total number of
human-caused bird deaths in Erickson’s study. There are, however, steps that can be taken in the
construction of wind-power turbines to minimize their impact on birds. The
American Bird Conservancy advises that lighting on turbines be minimized,
that tension wires and lattice supports should be avoided, and that
wind-turbine power lines be placed underground whenever possible. Already
more modern wind towers are being designed in ways that prevent birds from
perching on them (solving one of the problems with the Altamont Pass
towers) — and the turbine blades rotate much more slowly than those
in earlier designs. In addition, says the ABC, careful reviews of
potential wind-turbine sites should be conducted. Known bird-migration
pathways, areas where birds are highly concentrated, and landscapes known
for their popularity with birds should be avoided “unless mortality
risk has been analyzed and the likelihood of significant mortality has been
ruled out.” Wind farms should be situated on already disturbed land,
such as in agricultural areas, so as not to displace existing bird habitat
or travel corridors. Sites should also be reviewed for use by birds listed
under the Endangered Species Act. Ever-growing concerns about global warming and
pollution from fossil-fuel use demand that we move as quickly as possible
toward clean, renewable energy sources, even if they are as yet imperfect.
“When you look at a wind turbine,” says John Flicker, president
of the National Audubon Society, the world’s preeminent bird-advocacy
organization, “you can find the bird carcasses and count them. With a
coal-fired power plant you can’t count the carcasses, but it’s
going to kill a lot more birds.” Indeed, according to Erickson, for
every 10,000 birds killed by human activities, less than one death is
caused by a wind turbine. And if greenhouse gases are not reduced
significantly in the next decade, we could bear witness to a large number
of plant and animal extinctions in the coming years.
For more information:
American Bird Conservancy, www.abcbirds.org; American Wind Energy
Association www.awea.org; National Audubon Society, www.audubon.org.
Send questions to Earth Talk, care of E/The Environmental Magazine,
P.O. Box 5098, Westport, CT 06881 or e-mail earthtalk@emagazine.com.
This article appears in Apr 12-18, 2007.
