Cal Butchkoski clutched the edge of a cliff and delivered some bad news.
Moments earlier, Butchkoski, who is a biologist with the Pennsylvania Game Commission, repelled down the northern Luzerne County cliff to check on a known peregrine falcon nest tucked into a crevice. The Game Commission was hoping to retrieve chicks from the nest to band them as part of a population study on the state endangered raptor.
After inspecting the nest, Butchkoski climbed back up the cliff and reported that all he found was a patch of down feathers, evidence that there was a chick but it had been preyed upon. No other chicks or eggs were present but two adult falcons did circle overhead, keeping an eye on things.
It wasn’t the news that Arthur McMorris, peregrine falcon coordinator for the PGC, wanted to hear.
McMorris suspected a great-horned owl was to blame for the dead chick, but he wasn’t ready to give up hope on the site.
“I don’t like the fact that the adults didn’t care you were there, but I’d still like to check the other ledge,” McMorris told Butchkoski as he readied his ropes for a jaunt down the other end of the cliff face.
There are approximately 38 peregrine falcon nest sites in the state, according to McMorris. Only four are on cliffs — locations that McMorris said are crucial to the falcon’s recovery. That’s what makes the Luzerne County site — and the possibility that it harbors young — important.
A nest made by any bird species isn’t considered successful unless at least one chick fledges, or leaves, the nest. Most peregrine nests are in urban areas on manmade structures such as buildings and bridges — far removed from their natural nesting habitat.
McMorris said it’s not really understood why peregrines in the state seem to prefer urban areas to cliffs. It could be the seemingly easy living, he said, as cities have an abundant food source — pigeons — and relatively little pressure from predators.
But nesting in an urban environment still poses several risks, according to Patricia Barber, endangered bird biologist with the PGC.
“Cities provide a lot of challenges that the birds wouldn’t encounter in a natural environment, such as flying into windows, traffic and diseases. Out here, the prey base is cleaner and that’s not as much of a problem,” Barber said.
McMorris, Barber and other agency biologists have drafted a 10-year management plan for peregrines that contains goals needed to eventually de-list them as endangered in the state. One of those goals is getting the falcons to start nesting on their natural cliff habitat again and leave the cities behind.
The fact that most still prefer to nest in cities concerns Barber.
“That’s something we need to get a little better understanding of,” she said. “We need them back on natural cliffs.”
Because cities aren’t the type of habitat that the biologists would like to see peregrines use, successful nests in urban environments are only counted as one-fourth of a nest, as opposed to a cliff site which is counted in its entirety.
Another goal in the management plan is to have at least half of the 44 historic nest sites used again. Last week McMorris and Barber were at the Luzerne County cliff as they made their way across the state checking for young in known nesting locations.
“Peregrines are doing well to a degree, but there’s still a lot of challenges,” Barber said. “Especially when you consider that three-quarters of the fledglings die every year.”
Back on the Luzerne County cliff, Butchkoski made his way back up from the second ledge as McMorris and Barber eagerly waited at the top for good news.
On this day, however, that didn’t come.
At the second possible nest site, Butchkoski reported finding a broken egg. McMorris said it appeared the egg had been eaten by a mammal, such as a raccoon.
“This is the first year this nest site has failed,” McMorris said as he packed his gear in preparation for the next stop on the falcon banding tour.
There is only a 10 day window for the biologist to check all the falcon nests in the state for young. So far, McMorris said, the fledgling numbers are looking good, but there are still nests where the young haven’t left.
That means the biologists have a lot of miles to travel and little time to do it as they attempt to get a handle on a species that one day could follow the successful recovery path of the bald eagle.
“We’re working some 80 hour weeks,” McMorris said. “But I don’t mind it. I’d rather be tired at the end of the day than bored.”