Peregrine Falcons, a Threatened Species in Pennsylvania, are gradually making a comeback after being completely wiped out in eastern North America by DDT in decades past. There are only 57 nesting pairs of peregrines in the entire state, and only 13 of them nest on cliffs; the remainder nest on man-made structures. Further, only 3 of the nest cliffs are used by climbers, so those are the only sites where portions of the cliff need to be closed, and only for the nesting season, February 15 to July 31. Only the portion of the cliff within 250 yards of the nest needs to be closed; the rest can remain open, and the closed portion can be opened again once the young have fledged. During the nesting season, peregrines are very sensitive to disturbance: human disturbance during this time leads to nest failure or abandonment. Additionally, peregrines fiercely defend their nest sites from intruders, and can be quite dangerous to anyone disturbing them. Cliff nesting is crucially important to the recovery of peregrines; when they nest in unnatural, man-made locations (bridges and buildings), many of the young falcons die by falling into the river and drowning, getting hit by cars, colliding with glass windows or buildings, and other hazards of the urban environment. We ask your cooperation in allowing these magnificent birds, the fastest animals on earth, to nest at this cliff. This is a collaborative effort between climbers, wildlife biologists and conservationists to protect our outdoors and the wildlife we share it with. For more information and updates email: ctsnature@yahoo.com.