LAKE FOREST – An 11-week-old golden eagle lay on an examination table at the Serrano Animal & Bird Hospital for his preflight inspection.
Peter Bloom, a raptor biologist, took blood and feather samples so he later could study the bird’s health and genetics. He attached a tiny backpack containing a cellphone, GPS and a solar panel to the raptor’s back, allowing him to monitor the bird in the wild.
The raptor was rescued from a water reservoir near Dove Canyon during a recent heat wave. Bloom believes he may have floated down slope and found water, but then became immersed in it. When his feathers became waterlogged, the eagle was unable to lift off.
For a week, he has been nursed back to health by Scott Weldy, a wildlife veterinarian who operates the Lake Forest clinic and works with birds of prey at local zoos and wildlife refuges.
The young bird – already with a 4-foot wingspan – has been packing on weight with an around-the-clock diet of 20-30 frozen rodents and day-old chicks. He’s now at 8 1/2 pounds, a 1 1/2-pound gain from when he was found.
On Friday, he became the first fledgling golden eagle to join an ongoing program conducted by the U.S. Geological Survey to study the effects of development and population on golden eagles nesting in coastal California.
Researchers began trapping adult golden eagles in 2014 to better understand their movement. To date, 28 eagles have been captured and released across Orange, Riverside and San Diego counties. In Orange County, the study is funded by a California Department of Fish and Wildlife grant.
Although the golden eagle is one of the largest birds of prey in the Northern Hemisphere, its numbers have dropped in Southern California, Bloom said. Through the study, scientists hope to pinpoint the effects of development, including housing, wind power and land use as it relates to eagle habitat.
“We’re trying to do an objective assessment of conservation plans in some of the open space areas in central Orange County,” said Robert Fisher, a research ecologist who runs the program for the USGS in San Diego. “The 3D units tell us what places the bird visits and how high off the ground they fly if they cross a freeway. We can see them every 15 minutes and in real time.”
The fledgling eagle is the fifth golden eagle caught and released in Orange County. USGS data show three of the other four birds have left the area. Golden eagles need big, open spaces and often are spotted in places such as Wyoming and Montana.
Two of the O.C. eagles flew north through Walnut and the San Gabriel Mountains, Fisher said. Only one stayed in the county and now lives behind Irvine Lake.
The fourth eagle, released in Chino Hills, flew to the Santa Ana Mountains, then to Camp Pendleton. He headed back over the mountains, across Diamond Bar and Pomona, crossed the San Gabriel Mountains to the Tehachapi Mountains, then glided over the Owens Valley and into Nevada. He settled in Paradise Valley, a wide-open area with lots of land, Fisher said.
“He moved from sea level to a 9,000-foot peak,” Fisher said.
Fisher said he is optimistic the fledgling released near Dove Ranch on Friday will survive.
“He’s already been up and flying. The backpack won’t affect him. And if he has a problem, it will tell us where he is so we can recover him again,” Fisher said.
He’s also interested to see whether the eagle’s blood tests indicate a genetic link to another eagle in the study. “We want to see if any of those are his parents,” Fisher said.
The eagle was released on the hill over the reservoir where he was found near Dove Canyon. He put out his wings, pulled up his legs and glided down the canyon to the left edge of a hillside. Then he plumped his wings again and flew to another hillside and stopped.
“This is the best chance he has to make it,” Weldy said. “He’ll rejoin his parents, and they’ll teach him to be an eagle.”
Contact the writer: 714-796-2254 or eritchie@ocregister.com
