Falcons Must Move to Cliffs to Complete Recovery

State ornithologists say peregrine falcons must repopulate their natural cliff habitats before they can be taken off the Pennsylvania Game Commission’s endangered species list. However, the process is slow and sometimes frustrating, as past relocation efforts have failed.

While Pennsylvania’s peregrine nesting sites have increased from zero in 1964 to 29 today, only four of those nests are on cliffs, where peregrines lived before repopulating in cities.

The Game Commission’s peregrine management coordinator Arthur McMorris says the birds now occupy buildings, bridges, and smokestacks. He says while that’s fine for rebuilding the falcon population, fledglings falling from their nests has become a problem.

“If they fall out of the nest and the nest is on a cliff ledge, what typically happens is they will slide down to a lower ledge, and their parents take care of them there and everything’s fine,” says McMorris. “In the city, if they fall out of the nest, they end up on the sidewalk, in the street, in the river, whatever, and they perish.”

McMorris says it’s not a simple matter of introducing young falcons bred in captivity into cliff habitats. Past efforts to do so have resulted in all of the peregrines being eaten by great horned owls.

Adults are also resistant to relocation, so ornithologists are simply hoping for a migration to more natural habitats. McMorris says while it’s bound to be a slow process, cliff populations will increase more rapidly as more falcons populate cities as well.