30-year-old golden eagle from Sheridan second oldest in US
Date posted: April 18, 2014
SHERIDAN — A golden eagle from the Sheridan area has entered the record books as the second oldest golden eagle found in North America with an identifying leg band.
The eagle was found on March 19 on Soldier Creek Road by a local resident who saw the dead bird and alerted Wyoming Game and Fish Department officials.
“It was reported by an individual who was driving on Soldier Creek Road and saw it and at first, thought it had been shot,” WGFD Sheridan Senior Wildlife Biologist Tim Thomas said.
Thomas responded to the call and found that rather than being shot, the bird was under a utility pole and had wounds that were consistent with electrocution from a power line.
It was at this time that he also discovered that it had a small metal band attached to its leg.
Bands are often used by biologists on birds as a research tool in an attempt to learn more about their habits. The bands, made of plastic or aluminum, have a unique set of identifying numbers.
When a bird is found with a band, the finder can call or email the eight- or nine-digit number on the band to the U.S. Geological Survey’s Patuxent Wildlife Research Center Banding Laboratory, which serves as the national receptacle for all bird band information.
Thomas sent the numbers to the center the day he picked up the bird and received a surprising report back. According to its records, the laboratory reported that the bird had been banded as a fledgling in a nest in June 1983 near Gillette, giving it an estimated age of 30 years and nine months. This age ties for second place with a bird from Colorado in the laboratory’s longevity records.
“They requested pictures of band and bird to verify since it is so old,” Thomas said.
According to the laboratory’s website, the oldest recorded banded golden eagle was found in Utah in January 2012 and was aged at 31 years and seven months.
Thomas noted that while waterfowl with leg bands are often reported when they are harvested by hunters, other species with leg bands are reported less commonly.
In fact, he said this is only the fourth bird he has recovered with a leg band in his 22-year career.
To place a band, biologists often employ a mist net, which has very fine threads which will trap a bird that flies into it, but does not harm it. The biologist then gently handles the bird, placing a band around one leg, taking measurements and then releasing it. The band is small and lightweight and does not interfere with the bird’s movement or flight ability.
The biologist records the location of where the bird was captured, the date, estimated age and gender of the bird. The information is then sent to the Patuxent Wildlife Research Center. If a bird with a band is later found, the center provides the finder with all of the relevant information about it.
Thomas said that both he and the biologist who originally banded the golden eagle believed the bird to be a female, though a necropsy is the only way to positively identify the gender.
“Based on the size of the bird, females tend to be larger than males, and also the biologist who banded the bird, when he banded it, took some measurements that indicated it is a female,” Thomas said.
Thomas said the bird will soon be sent to the U.S. Fish and Wildlife Service’s National Eagle Repository in Colorado. The repository distributes eagle parts to officially recognized Native American tribes for use in religious ceremonies. Possession of eagles or eagle parts, including feathers, is otherwise prohibited by federal law.
Golden eagles are found in the U.S. and Canada and are generally a solitary species, though pairs are often found together through the year and form bonds that last years and possibly the lifetime of the birds. They are very large, growing to a length of 35-inches with a wingspan of 84-inches. Their diet consists of a variety of prey, including prairie dogs, rabbits, squirrels, marmots and deer and antelope fawns, as well as other birds such as herons, waterfowl and game birds. Golden eagles became protected by federal law in 1963.