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Recount Her Life - Story and Legacy

Tribute to the Resident Female Peregrine 4/4 - A Memorable and Remarkable Falcon

September 2010

The Rachel Carson State Office Building's in Harrisburg, PA, resident female Peregrine Falcon, 4/4, a state-listed endangered species, arrived on the 15th floor nest ledge in early May 1999.  Based upon her alphanumeric leg band information, the female fledged from the Girard Point Bridge iPeregrine Falcon 4/4n Philadelphia in the summer 1998.  Dan Brauning, an Ornithologist with the PA Game Commission (PGC), banded her and her siblings before they fledged.  She was the first falcon from a bridge nest site to be rediscoved at another site in Pennsylvania.  Based upon Dan's experience and observations from her banding, 4/4 came from a strong family line of extremely aggressive females, which would be seen in 4/4 and her female offspring.

When she arrived at the Rachel Carson Building in 1999, she was 12 months old and too young to reproduce, but hopes were high in 2000, when she would begin reproducing for the next ten years, laying 49 eggs and hatching 44 young--all chronicled live through the PA Falcon Cam.  4/4 was the second female at the nest site. In 1997, a banded female peregrine arrived on-site but failed to reproduce with the male for two seasons.  From her band code, biologists discovered that she fledged from the National Monument in Washington DC.  Her father was an escaped falconer's bird and his breeding was half Prairie Falcon, half Peregrine Falcon. As a result of this hybridization, it was determined that any offspring, including this female, were rendered infertile.  The female was live trapped in the spring of 1999 and sent to the National Aviary in Pittsburgh where she served in educational programming.

The Rachel Carson Building houses the offices of the Pennsylvania Departments of Environmental Protection (DEP) and Conservation of Natural Resources (DCNR). The building is aptly named for Rachel Carson the author of Silent Spring and a Pennsylvania native, who exposed the dangers of pesticides, particularly DDT, in her landmark book.

4/4 was legendary in her aggressive defense of the nest site and young eyases.  The area around the building is locally-known as the "no-fly zone," because 4/4 would chase away birds and kill raptors that strayed too close to the building.  Redtailed and Cooper's Hawks are the most common victims of her wrath. Redtails can be a threat to Peregrine nestlings and Cooper's feed on the same prey base--other birds.

Like all falcons, 4/4 had long pointed wings and rapid, steady wing beats in flight. 4/4 could reach a speed of more than 200 miles per hour in a vertical dive called a stoop; in level flight 4/4 averaged about 60 miles per hour.

4/4 and the Redtailed Hawks were fierce rivals.  In 2004, a Redtailed Hawk carried off and killed a young falcon eyas from the ledge.  Since then, 4/4 went after Redtailed Hawks, who entered the no-fly zone, with a vengeance--chasing them into nearby buildings, parking garages, the train station and other nearby structures, or simply knocking them out of the sky to often land on the ground stunned or even dead.  Her fury extended to PGC's banding crew, who, year after year, climb out onto the 15th floor ledge to band the young eyases.  Every year, 4/4 grew more and more intolerant of ledge visitors.  So much so, that in 2009, PGC Wildlife Conservation Education Specialist, Joe Kosack, was scratched on the face by 4/4's talon as he opened the ledge window to climb out.  PGC's Pennsylvania Peregrine Coordinator, Dr. Art McMorris, has been hit in the back by 4/4 while banding.

In 2005, the resident male Peregrine, Carson, was found injured at the train station.  He was rehabilitated and housed at Zoo America as an educator bird.  Carson was the name given to him as now, no longer free and wild, he was valued as a caretaker's companion and endangered species icon in outreach programming.  Ironically, a squirrel chewing through netting facilitated Carson's escape from Zoo America.  In any case, he will finish out his remaining days as a free and wild raptor, as it should be.  After 52 days, a new male, who was banded in May 2003, on the Walt Whitman Bridge in Philadelphia arrived and bonded with 4/4.  This new resident male is a superb hunter and mate.

In September 2010, 4/4, at the age of 12, was unable to defend the ledge from a challenging young female peregrine.  There were reports that a dead falcon was seen near the train station with a description that seems, with little doubt, to be 4/4.  There were reports of a two hour battle, so if the combatants were 4/4 and the new female, the victory was hard earned.  There also were reports that she may have been ill, but since no carcass was recovered, no testing could be done to confirm this.

Unfortunately, this isn't a happy ending for 4/4--because of a lack of timely reporting and detailed information, she wasn't able to be recovered for rehabilitation.  As humans, some may see this is sad, but this is part of nature that ensures the survival of this wild predator.  That said, we will certainly never forget this memorable and remarkable falcon.

But, the story of the Rachel Carson Building peregrines continues to unfold.  There is a new, unbanded adult female who is pair-bonding with the resident male.  Falcon watchers will need to continue watching the new pair to witness their progress in the months to come.