Western Pennsylvania’s improving environment attracts growing number of eagles
It’s hard to miss the white head and tail on a 2 1⁄2-foot-tall bird in the bare trees lining Loyalhanna Creek in Westmoreland County.
More than 20 bald eagles can be found congregating near the outflow of the Army Corps of Engineers Loyalhanna dam in Loyalhanna Township during winter days when other waterways are frozen.
It wasn’t always that way though, park ranger Mark Keppler said.
“When we did the surveys in the early 2000s, at first it was a joke — we saw nothing,” he said.
Cleaner water and the benefits of Pennsylvania Game Commission’s reintroduction program of the once federally endangered bird bolstered the bald eagles’ presence in the region.
The Corps, in conjunction with other federal agencies including the Fish and Wildlife Service and the Department of the Interior and environmental groups, have been surveying the eagles nationally since 1979 to monitor their winter populations.
The Corps has been involved with the study because it wants to ensure its facilities, located at locks and dams, won’t disturb the birds, according to John Chopp, a biologist in the Corps’ Pittsburgh District.
The congregation of wintering eagles is primarily food-driven.
When lakes, ponds and creeks freeze over, the eagles gravitate to open water often found near dams and electrical power plants.
They flock to the outflow of Loyalhanna dam, where there is a healthy bounty of gizzard shad, which are sensitive to the low temperatures.
As a bonus, the outflow of some dams is so powerful that it can stun or injure the fish, providing easy pickings for these fisher birds, which also eat carrion.
“The food is easy for the eagles here,” Keppler said. “They like ducks, too.”
Quite a sight
Also congregating at the site are local wildlife photographers who line up near the outflow to photograph the majestic birds, usually at close range and, if they’re lucky, at play.
“They can do barrel rolls in flight, which is breathtaking to witness,” said Steve Gosser of Arnold, an amateur wildlife photographer.
These wintering grounds give people a sure-fire way to see the birds, and their antics can be exciting.
“When you got a whole bunch of eagles in a small area, you’re bound to see something,” said Patti Barber, a biologist with the Pennsylvania Game Commission.
“They chase each other, harass other birds and will steal fish from ospreys and other eagles,” she said.
Cars frequently stop along Loyalhanna Dam Road, where it’s commonplace to see a long telescopic camera lens poking out of the open window of a parked car.
“It’s a big attraction,” said Keppler, whose office has a conspicuously placed pair of binoculars resting on the sill of a large picture window overlooking the dam.
The eagles practically pose for the cameras, sitting like sentries on limbs close to the water. From a distance, the large brown birds can blend into the stands of sycamores and silver maples that have long since shed their leaves.
The brown landscape brightens with a spot of white, a mature eagle’s head.
However, the majority of birds are the brown and tawny young eagles who won’t acquire their dapper white head and tail until 4 or 5 years of age, when they will be ready to mate.
But for now, these mostly bachelors and bachelorettes are on the hunt.
“If you are an adult eagle with territory, you’re going to stay on your territory,” Barber said. “You don’t want to risk some young upstart taking it over.”
But the younger eagles roam widely from where they were hatched in search of food and territory.
On the prowl
The juveniles who are older, but not quite adults, are cruising for a mate.
“Their hormones are pumping this time of year,” Barber said.
Since good breeding territories are dear — waterways with fish and large trees to support mammoth eagle nests — near-mature birds are looking for a “breeding vacancy.” Known as “floaters,” these birds are constantly scouting for a territory to make their own.
“If an adult eagle dies today, an adult of the same sex will replace them as fast as possible,” Barber said. “It can happen in less than a day.”
Where the birds are
The region’s most productive area closest to the Alle-Kiski Valley for wintering eagles is the Loyalhanna dam, where the Corps counted nine eagles on a single day in early January.
The number of eagles at the dams is influenced by the amount of ice cover on local waterways. The more ice, the more birds.
North of Pittsburgh, Shenango dam outside Hermitage had the highest number of eagles for the Corps’ 2017 survey, attracting 27 on a single-day count.
Last year, the Corps’ midwinter survey tallied 91 eagles at its locks and dams in Pennsylvania, Ohio and West Virginia, Chop said. This year, that number bumped up to 97, he said.
But that’s a paltry turnout when compared to Conowingo dam in Harford County, Md., which can attract up to 100 eagles in a day, according to local news reports.
More eagles living here
The increasing number of Pittsburgh-area eagles also is because of the growing resident population, like the famously visible pairs in Harmar and the Hays section of Pittsburgh.
And it is poised to grow more in Southwestern Pennsylvania, according to Barber. The Game Commission counted 276 active eagle nests last year in the region, with the actual number likely greater because there aren’t enough volunteer observers to report all of the nests, Barber said.
Eagle populations haven’t reached saturation yet, she said.
But they are filling in, according to Barber. On some sections of the Susquehanna River, there are nests only a quarter-mile apart.
NOTE: This story has been updated from the original to correct the spelling of John Chopp’s last name.
Mary Ann Thomas is a Tribune-Review staff writer. Reach her at 724-226-4673 or [email protected].