Twenty years of bald eagles breeding along the Upper Delaware River
December 30, 2013 —
My interest in birds was casual when I was younger, but got a boost in the late ‘70s when I returned to the U.S. from military service and started flying small aircraft over our region's scenic Upper Delaware River Region as a way to unwind.
Aside from the scenic ridges and swift water rapids below, I kept an eye out for birds. In this bird-rich region, what started out as a safety necessity became more and more a quest to identify the rapidly growing dots that quickly appeared as feathers and wings whizzing by at cruising speed.
Birds like vultures and hawks were easily recognizable, but occipiters such as sharp-shinned hawks were smaller and more of a challenge. Geese and waterfowl were present, with flocks easy to spot during migration season. One species was missing though; during my early flights, I saw no bald eagles—no majestic dancers of the sky to share the airspace with.
Eagles, taken for granted by many people today, can be seen throughout the region, and all of our local counties have several occupied bald eagle nests. This wasn't always the case; the effects of DDT caused eagles, as well as several other bird species, to experience reproductive difficulties in the form of thin and brittle eggs that would not endure the incubation process.
In the late 1970s, Pennsylvania was down to three breeding nests and New York was down to a single breeding pair that could not reproduce due to DDT effects, before the chemical was banned. The bald eagle was on the verge of extirpation (local extinction) in NY and PA, and there were no nests within our region.
In 1976, New York State (NYS) initiated a bald eagle reintroduction program where eaglets from Alaska’s plentiful population were placed in cages on man-made elevated nesting platforms called "hacking towers." Eaglets were fed by people who stayed out of view of the birds so the eaglets did not "imprint" on humans as a parent.
At around 12 weeks on, the cages were opened so the eaglets could perch on branches placed on the cages and eventually make their first flight, or fledge. Four years later near Watertown, NY, a pair of these “hacked” eagles was found successfully breeding at a nest of their own. In 1980, the NYS Department of Environmental Conservation (DEC) went large scale with the project, hacking close to 200 eaglets during the next nine years. PA initiated its own reintroduction in 1983.