Two golden eagles that soared along the Allegheny Front ridge in
Central Pennsylvania late last year and are now gliding over the hills
of West Virginia and Kentucky might one day help determine where new
windmills will be built in the eastern part of the United States.
The wide-winged raptors are wearing tiny radio telemetry
transmitters that allow National Aviary researchers to track their
migration routes and eventually develop the first bird's-eye-view data
showing where electric wind turbines should be built and not built to
minimize the killing of eagles and other big birds.
Most wind turbine development has occurred without any scientific
research on the consequences to migrating birds, according to Todd
Katzner, director of conservation and field research at the National
Aviary in Pittsburgh.
That has increased the risk that the turbine blades, some more than 100 feet long, will become bird slicers and
``Our broader goal is to identify ways in which wind power can be
developed safely,'' Katzner said. ``To say that we're looking at the
effect of wind power on birds is partially true, but we're really
trying to identify areas of high and low risk for windmill
More than 500 of the majestic raptors, Aquila chrysaetos, traverse
Pennsylvania and nearby areas twice a year during spring and fall
migrations, as do bald eagles, osprey, falcons and a variety of hawks.
Many of those raptor species, some of which are endangered or
threatened like the eastern golden eagle, follow narrow corridors.
Those airborne pathways, which the birds follow to take advantage
of buoyant updrafts, run along the very ridge lines that wind power
companies are eyeing for development.
``Not many folks are aware that there's a thousand golden eagles
flying through Pennsylvania in November and December,'' Katzner said.
``That sounds like a substantial number, but if you put turbines in
the wrong place, they could have a significant impact on the
Wind power is the fastest growing energy technology, and
Pennsylvania is the leading producer of wind energy east of the
Mississippi River, generating 153 megawatts, enough to power 70,000
Given that the state's goal is to boost wind power production
to more than 3,000 megawatts, a 20-fold increase, over the next 15
years, the potential for mayhem along the Appalachian ridges is a
No one not birders, the wind power industry, nor the government
agencies that issue permits for turbine sites wants a repeat of the
siting debacle that occurred at Altamont Pass, near San Francisco,
where 4,000 wind turbines were constructed on rolling grasslands that
contain a large ground squirrel colony and are prime foraging grounds
for migrating golden eagles and other raptors.
Estimates put the number of birds killed annually at more than 4,700, about 1,300 of
The wind power industry caught another black eye in 2004, when it
was discovered that hundreds of migratory birds and up to 4,000 bats
were killed by the whirling blades of 44 turbines in the Mountaineer
Wind Energy Center on Backbone Mountain in West Virginia.
Heavy bat mortality also occurred at the 20-turbine wind farm in Myersdale,
Somerset County, which came on line in 2004.
``Any kind of additional information that would help make better
decisions is something we would be interested in,'' said Frank
Maisano, a spokesman for a coalition of wind power developers in the
mid-Atlantic region. ``But if we learn about a bird's flight path,
that shouldn't automatically disqualify a site from siting
Christine Real de Azua, a spokeswoman for the American Wind Energy
Association, said wind energy's impact on birds was a ``very important
issue,'' but was quick to add that fewer than one of 10,000 birds that
die because of human causes is killed by a turbine. Most are killed
because they run into buildings or windows or by house cats.
``We have a very light impact now, and if we can make it even
lighter, that's a very good thing,'' she said. ``The industry is
committed to researching, responding and identifying solutions.''
(Distributed by Scripps Howard News Service, www.shns.com.