CODY, Wyo. (AP) — The rush to build wind farms to fight climate change is clashing with the conservation of one of the U.S. West’s most spectacular raptors — the golden eagle — as the species teeters on the brink of decline.
Ground zero in the conflict is Wyoming, a stronghold for golden eagles that soar on seven-foot (two-meter) wingspans and a favored location for wind farms. As wind turbines proliferate, scientists say collision deaths could reduce golden eagle numbers that are considered stable at best and likely to decline in some areas.
But climate change looms as a potentially bigger threat: Rising temperatures are expected to reduce the golden eagle’s breeding range by more than 40 percent later this century, according to an analysis by the National Audubon Society.
This leaves golden eagles doubly vulnerable – to a changing climate and to wind power being promoted as a solution to this warming world.
“We have some of the best golden eagle populations in Wyoming, but that doesn’t mean the population isn’t at risk,” said Bryan Bedrosian, conservation director at the Teton Raptor Center in Wilson, Wyo. “As we increase wind development in the U.S., that risk increases.”
The hundreds of feet of turbine blades are among the myriad threats to golden eagles, who are routinely shot, lead poisoned, hit by vehicles and electrocuted on power lines.
The vulnerable position of golden eagles contrasts with the conservation success of their cousins, the bald eagles, whose numbers have quadrupled since 2009. There are about 350,000 bald eagles in the U.S., compared to about 40,000 golden eagles, which need much larger areas to live. survive and are more likely to have problems with humans.
Federal officials have sought to limit deaths from wind turbines, avoiding any slowdown in the development of wind power – a key part of President Joe Biden’s climate agenda.
In April, a Florida-based power company pleaded guilty to criminal charges after its wind turbines killed more than 100 golden eagles in eight states. It was the third conviction of a major wind company for killing eagles in a decade.
Suspended from a rope 30 feet (9 meters) above the ground with a canvas bag slung around his neck, Bedrosian shouldered into a golden eagle’s nest perched on a cliff ledge. The scientist grabbed the young eaglet in the nest, pulled a leather hood over its head, then stuffed it into the bag.
The six-week-old bird was carefully lowered and removed by Bedrosian’s colleague, Charles Preston, with a zipper around its legs as a precaution against the inch-long claws.
“The key is not to forget to cut the zipper later,” Bedrosian said.
The eagle went on a scale – about seven pounds (3.2 kg). Bedrosian drew some blood from a feather to test for lead exposure, and Preston clamped a metal identification band to each leg.
Golden eagles don’t mate until age 5 and produce about one chick every two years, so the deaths of adult eagles have a larger population impact, Bedrosian said.
Illegal shooting is the biggest cause of death, killing about 700 golden eagles a year, according to federal estimates. More than 600 die annually in collisions, including cars and wind turbines.
“Wind mortality was not something for golden eagles 10 years ago,” Bedrosian said. “I don’t want to choose air as the only thing. … But it’s the additive nature of all these things and they add up quite a bit. Vehicle strikes are on the rise. Climate change is increasing. The wind is picking up.”
The recent criminal prosecution of a subsidiary of NextEra Energy provided a glimpse into the scope of the problem.
The company was ordered to pay more than $8 million in fines and restitution for killing eagles at wind farms in eight states.
NextEra remained defiant after the plea deal: Its president said bird collisions with turbines were unavoidable accidents that should not be criminalized.
Duke Energy and PacifiCorp previously pleaded guilty to similar charges in Wyoming. North Carolina-based Duke was ordered in 2013 to pay $1 million in fines and restitution and a five-year suspension after the deaths of 14 golden retrievers, and a year later, Oregon-based PacifiCorp received $2.5 million in fines and a five-year suspension for 38 killed eagles.
The number of wind turbines nationwide has more than doubled in the past decade to nearly 72,000, according to data from the US Geological Survey.
To control the impact on eagles, federal officials want companies to obtain permits that allow them to kill certain birds if the deaths are compensated. Companies then pay utilities to retrofit power poles so eagles can’t easily be electrocuted. Every 11 post-positioned poles usually counts as an eagle death avoided.
Nationally, 34 permits last year allowed companies to “take” 170 golden eagles – meaning many birds were killed by eddies or lost due to impacts on nests or habitat. An Associated Press review of public records shows most are wind farms.
“It sounds silly but it’s realistic. Eagles will be accidentally killed in wind farms,” said Brian Millsap, head of the wildlife service’s eagle program. “We need to reduce other things that will allow wind energy to grow.”
The nests where Bedrosian and Preston are doing population studies are about 60 miles (96 kilometers) from the nearest wind farm — 114 turbines that PacifiCorp began operating about two years ago near the Wyoming-Montana border.
Personnel at the construction site scan the skies with binoculars for eagles and can shut down the turbines when they approach. Ten PacifiCorp wind farms have permits that allow the accidental killing of eagles, according to the company.
Company representatives declined to say how many eagles have died at those facilities. They said PacifiCorp is building a “bank” of aftermarket power poles to offset eagle deaths and also wants to try new approaches, such as painting turbine blades to make them more visible and easier to avoid.
“We work as hard as we can to prevent and minimize (deaths) up front, and then anything we can’t we mitigate on the back end,” Brown said.
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The Associated Press Health and Science Section is supported by the Howard Hughes Medical Institute Science Education Division. AP is solely responsible for all content.