Pennsylvania's nesting population numbers about a dozen pairs. All recent nests have been on buildings and bridges in urban settings. Peregrines remain an endangered species in the commonwealth. Nationally, however, peregrines were recently removed from the federal Endangered Species List. National delisting was a direct result of the bird's dramatic recovery across the country.
Underparts are whitish to buffy colored, broken by horizontal bars.
Birds up to two years old are marked with dark brown, rather than gray, on their wings and back. Like all falcons, the peregrine has long pointed wings and rapid, steady wing beats in flight. Records indicate the bird did not nest in Pennsylvania from about 1959 to 1987. It was estimated to number about 350 nesting pairs in the early 1900s. The true eastern peregrine falcon is extinct.