Peregrine falcons coming back
As Cal Butchkoski dangled by a rope at the edge of a cliff in Luzerne County, he delivered some bad news to a group of onlookers standing above.
Butchkoski, who is a biologist for the Pennsylvania Game Commmission, had just repelled down the cliff face to inspect a peregrine falcon nest. In it he found a few bits of down feathers from a chick.
Art McMorris, peregrine falcon coordinator for the agency was disheartened by the finding but didn't give up hope. There was another possible nest site on the cliff, and Butchkoski repelled down that face with a bit of renewed enthusiasm.
As a pair of falcons circled the sky above the cliff, in a few minutes Butchkoski climbed back up.
All he found was broken egg shell.
McMorris and other commission staff are busy this month surveying peregrine falcon nesting sites. A nest is considered successful if at least one chick fledges – or leaves the nest. Despite the fact that the Luzerne County cliff showed evidence that at least one chick had hatched, it wasn't considered a success because the bird never grew strong enough to leave.
The bit of down and the broken egg were signs of predation, McMorris suspected. A great-horned owl likely got the chick, and a raccoon probably swiped the eggs in the other nest site, he suspected.
It was a depressing find, but one that proved how harsh nature can be at times. McMorris said it was the first time the falcons failed to fledge young at this particular location, so there have been plenty of success stories over the years.
And while the peregrine falcon is state-listed as endangered, McMorris said the numbers are improving. Just how much he won't know until a few more weeks when the commission crews have finished their surveys.
But so far, he said, things are looking better.
Surprisingly, the Luzerne County site is one of only four cliffs in Pennsylvania where peregrines are known to nest. Most of the locations are in urban settings – tall buildings and bridges primarily.
And those that nest in the cliffs are prone to predation. McMorris said urban falcons are frequently killed by traffic and flying into windows. While urban areas provide a bevy of food for peregrines, mainly pigeons, such locations are not without their hazards as well.
Add it all up, and it's amazing that Pennsylvania's peregrines are making a bit of a comeback despite of the challenges.