Feature - Peregrine Falcons Make a Comeback
Photo
Game Commission Photo

By Joe Kosack, Wildlife Conservation Education Specialist, Game Commission

The peregrine falcon appears poised to follow the bald eagle on the road to recovery in the Commonwealth, according to the Pennsylvania Game Commission, which has managed this state-endangered raptor's reintroduction over the past 30 or so years.

But the birds of prey aren't too keen about continuing to participate in the wildlife management program that has prompted their return. In fact, they've become downright inhospitable to Game Commission personnel who annually visit their nests to perform health checks and band their young.

Fortunately, the biggest news on peregrine falcons this spring isn't who got smacked or raked during nest visits. It's about the phenomenal - almost unbelievable - increase in peregrine nests in Pennsylvania. This year there are 24 peregrine nests instate or on bridges on state borders. There were 15 nests statewide last year.

Of course, not every nest is a successful venture, and surely that will be true of some nests this year. But a majority will produce young and further the ongoing peregrine recovery. Thirteen nests were successful last year and led to the fledging of 42 young. Three decades ago, that number would have exceeded America's peregrine population east of the Mississippi River. Today, it serves as a shining example of what good can be accomplished with sound wildlife management and environmental reform.

"Pennsylvania has had 15 peregrine falcon nests for the past two years, which made those years the most productive since DDT was banned in America," explained Dr. F. Arthur McMorris, who oversees the Game Commission's peregrine falcon program. "But this year is really something special, because we've seen the largest increase in nests since our peregrine recovery began. As recently as 1997, there were only eight nests in the state."

Falcons were suffering horribly from the 1940s through the 1960s from the poisonous effects of bio-accumulating DDT in their bodies. The insidious insecticide - banned nationally in 1972 - gradually poisoned the birds and made the shells of the eggs these birds laid so brittle, they broke when sat upon. The same year DDT was banned, peregrines were listed as a federally endangered species. At the time, many thought they'd be extinct by 1980. Now, 35 years later, the birds are back in a big way, having successfully shaken free of the poisonous noose that slowly and silently strangled their once well-established Pennsylvania population, as well as many other species of birds.

"Peregrine falcons have made a remarkable recovery, and we're thrilled with their progress," explained Dan Brauning, who supervises the Game Commission's Wildlife Diversity Section. "But before we consider them secure, we'd like to see them occupy a larger number of historic natural cliff sites. Right now, only three of the 24 nesting pairs are on cliffs.

"So it's fair to say we really haven't achieved our peregrine recovery objective yet, because we still need more birds to reclaim more of Pennsylvania's 44 or so historic cliff nesting sites. But the progress in cities across the state, has been nothing short of incredible. The jump to 24 nests this spring absolutely floors the incremental one- to two-nest increases we've seen over the past 10 years."

New peregrine nests were established in the following counties: Allegheny, Beaver, Berks, Lancaster, Lehigh, Luzerne, Montour and Union counties.

Overall, more peregrines anywhere in Pennsylvania is a step in the right direction for this raptor's recovery. But seeing more nesting pairs on cliffs, instead of on buildings and bridges would qualify the ongoing recovery as more organically significant.

Peregrines made their big step back to natural nesting sites in Pennsylvania in 2003 when a pair used a cliff in the state's northern tier overlooking the west branch of the Susquehanna River. It was the first time peregrines used cliffs since 1957, when five pairs were nesting at cliff sites instate. Peregrines started nesting in Pennsylvania for the first time since their extirpation in the late 1980s, when they began nesting on bridges in the greater Philadelphia area.

Pennsylvania's three peregrine cliff nests are found in Lycoming, Luzerne and Union counties. The state would have had four cliff nests, but a pair abandoned another Luzerne County cliff nest it had used for two years to return to a bridge nest it had left previously.

"It wasn't exactly the type of behavior we expected to see, and we're at a loss to explain why it happened," McMorris said. "It could be related to disturbances or predators, or maybe nothing more than a move back to a site at which they were more comfortable. We'd have preferred they went to another cliff if they had to move, but then it really wasn't up to us!"

The Game Commission plans to visit at least 15 nests this spring to band and perform health checks on peregrine chicks. A banding occurred May 16 on the Gulf Tower in Pittsburgh, and for the second consecutive year, the adult female behaved aggressively toward Allegheny County Wildlife Conservation Officer Beth Fife and Land Management Group Supervisor Doug Dunkerley who removed the young birds from a ledge nest box about three dozen floors up.

"For the past five years, the female has worked feverishly to protect her young at the nest box, which makes removing them for banding even more of a challenge," said Fife. "Up until last year, she just dove at us. Last year that changed when she landed on the ledge, raised her wings and came at me. I netted her. This year, she stayed at the nest box and grabbed my gloved hand as I reached for a chick. She wouldn't let go so I had to take her off the ledge and inside to get her out of the way. We released her after the chicks were banded."

This week, Game Commission personnel banded peregrine chicks on the Rachel Carson Building in downtown Harrisburg at a nest-box where the adult female also has grown weary of intrusions to her 15th floor ledge overlooking Market Street. For the past two years, she has body-slammed the hardhat-covered head of an agency employee while either cleaning camera globes or returning chicks to the nest on the ledge.

"It will be surprising if she isn't waiting with her game-face on when we open the window this Thursday," Brauning said. "She's all business and 100 percent wild. But that is, quite frankly, the type of behavior we prefer to see in falcons."

The state Department of Environmental Protection's falcon page (www.dep.state.pa.us/dep/falcon) will carry a live Internet lesson and banding of the falcons, conducted by Brauning and DEP Director of Environmental Education Jack Farster, from 1 p.m. to 2 p.m., Thursday, May 24, from the Rachel Carson State Office Building's auditorium in Harrisburg.

Although peregrines were never really common in Pennsylvania, they historically nested at as many as 44 sites, mostly on cliffs. Some of their former nesting areas included cliffs near Dauphin, Huntingdon, Lewistown, Hyner, Palmerton and other riverside communities.

Peregrine falcons, also commonly referred to as "duck hawks," are strong fliers that hunt on the wing, diving from nose-bleed heights at speeds up to 200 miles per hour to snatch flying blue jays, flickers, starlings, pigeons and other like prey. The birds weigh from one-and-a-quarter to about two pounds and females are larger than males.

Links: Visit the Pittsburgh Falcons online

Visit the Harrisburg Falcons online


5/25/2007

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