Comeback Kids: The Resurgence of Bald Eagles in the Hudson River Valley

BY CHERYL SLAVIN

PHOTOS BY TOM McGUIRE UNLESS OTHERWISE NOTED

“Palisades welcomes two new residents,” bird watcher and enthusiast David Gottlieb wrote for Palisadesny.com in 2012. “A pair of bald eagles have built a huge nest on an old white pine in Sneden’s Landing overlooking the Hudson River. They can be seen soaring above the water where they hunt for fish, their favorite food.”

It was not so very long ago when a sighting like this would not have been possible in Rockland County, let alone the entire length of the Hudson River Valley. American Bald Eagles were chosen as the soaring symbol of a fledgling nation’s hopes and aspirations; yet despite their sacrosanct status, the eagles faced near extinction at the very hands of those same people they had been chosen to represent. Today, however, as they continue to rebound from the verge of decimation, America’s symbol has come to represent another true American quality: resiliency.

At the time when colonial homesteads still dotted the Rockland landscape, and Dutch was the predominant language, bald eagles were a common sight up and down the Hudson River corridor. An estimated half a million populated North America before the arrival of the Europeans. But by 1782 their numbers had diminished to between 25,000 and 75,000 throughout what would become the lower 48 states. Continued loss of habitat and indiscriminate hunting (farmers considered them pests that preyed on livestock) further eroded their presence, although New York still had up to 80 known nesting pairs prior to 1900. Finally, alarmed enough by the dwindling population, Congress passed legislation in 1940 protecting bald eagles from harassment from humans.

By then, however, a worse assault came in the form of chemical poisons—pesticides and heavy metal wastes—that entered the food chain through the soil and accumulated in eagle bodies. DDT in particular destroyed the eagles’ ability to absorb calcium; their bones became brittle and frail, and egg shells broke under the weight of the brooding parents. Bald Eagles were officially declared endangered in 1967, and the federal government finally banned DDT in 1972, but the damage had already been done. By 1960, New York had only one nesting pair left, and fewer than a dozen migratory birds. By 1976 the sole nesting pair had long ceased to produce any young.

Fortunately in New York State, the Department of Environmental Conservation came to the rescue. A fledgling agency itself (it had only been established in 1970), the DEC came up with an innovative, two-prong plan: hand-raise imported eagle hatchlings to be released in the wild—a process called “hacking,” and induce the one remaining nesting pair to “adopt” and raise as its own an imported eaglet. The program, commenced in 1976, succeeded beyond everyone’s expectations. By 1989 the goal of reestablishing 10 nesting pairs in New York State had been achieved, with a total of 198 nestlings released back into the wild. As the environmentalists had hoped, the eagles raised and released in New York State returned here to establish their own nests and rear their young. By 1995, bald eagles were removed from the federal endangered species list through these kinds of efforts all across the country.

“They are survivors,” says Ed McGowan, Director of Science and the Trailside Museums and Zoo at Bear Mountain. “They are naturally long-lived, up to 30 years in the wild, so they have had to be adaptable, be good at problem solving.” But the eagles also continue to receive a great deal of support from the humans who care about them.

“We had a nesting pair take up residence a few years ago in an oak tree about 40 feet away from the Stony Point Lighthouse,” McGowan recounts. “They fledged two young, and we had to shut down the lighthouse during nesting season, remove a geocache and set up a blind to prevent people from approaching and disturbing them. The site manager was concerned that she wouldn’t be able to carry out the regular July 4th programming, as it included musket firing and other loud noises.

As it turned out, the July 4 festivities were able to continue as planned. Later on, the nest became unstable and the birds abandoned it. There are, however, increasing sightings of nests on both sides of the Hudson. McGowan estimates that there are four or five known sites along the Rockland side, probably including the one in Palisades. Others have been seen in Snedens Landing, Piermont and Nyack, according to Gottlieb. Most naturalists, however, will not divulge exact locations, the better to protect the birds.

Especially during the winter months, though, eagle enthusiasts have plenty of opportunities to observe these magnificent raptors. As the resident population has grown, so too have the migratory visitors, eagles that travel south from Canada and northern New York and New England. An eagle’s diet is predominantly fish; therefore, as lakes and rivers freeze up north the birds come to hunt and fish along the open waters of the Hudson.

“The Hudson River is an estuary,” explains McGowan, “and the movement of the tides, as well as commercial traffic, prevents it from completely freezing over.” Warm water emissions from power plants, as well as inlets from tributaries, also keep the water open. Eagles are often spotted perched upon the ice floes, from which they dive into the water or settle down to eat their kill.

In addition to open water, the Hudson River Valley still has significant tracts of relatively untouched land available for eagle habitats, as well as an abundance of other food such as small animals. Eagles are also carrion eaters, and they are attracted to the train tracks that line both sides of the Hudson where much “train kill,” such as dead deer, can be found. Charlie Roberto, board member of the Bedford Audubon Society, notes that some people will even drag deer kill out for eagles to eat. Eagles are also opportunistic; Roberto has seen one eagle catch a fish only to have it knocked out of its talons by a second eagle and then caught mid-air. He has observed up to 11 eagles on one ice floe, fighting over one fish, a sight commonly reported by many eagle watchers. So far, however, the population has not reached its saturation point. Resident eagles and migratory birds mostly abide in peace, although there is the occasional squabble if a visitor comes too close to a nest.

Bald Eagles maintain “fidelity to location,” according to McGowan, which accounts for the return of pairs, mated for life, to the same nest (some nests can grow as deep as 6 feet over time) as well as the return of winter migrants year after year. This characteristic makes it somewhat easier for naturalists on both sides of the Hudson to undertake their yearly counts of the eagle population. Migratory birds will retire each night at shared roosting sites in trees that provide shelter from the wind and perhaps the added warmth of a southern exposure. Roosts of up to 100 eagles have been observed in Bear Mountain; similar numbers have been observed on the Westchester side as well.

The statistics gathered from these counts bear out the perception that bald eagles are continuing to thrive along the Hudson. Although the numbers fluctuate annually depending on weather and climate conditions, the overall trend shows a steady increase. According to the Rockland Audubon Society’s annual Christmas count, there were 44 bald eagles found in the survey area in 2012, up from 20 in 2011, up from 15 in 2010. McGowan does three counts in January and February and has counted as many as 254 during one survey. Tait Johansson, a naturalist with the Bedford Audubon Society, has seen similar congregations on the Westchester side during the annual BAS count. The DEC website reports that in 2010 New York had 173 breeding pairs which fledged 244 young.

The evidence of a robust and thriving Bald Eagle community also indicates a cleaner, healthier Hudson River and surrounding area. However, there is still much more to be done.

“We need continued vigilance,” states Phyllis Bock of the Teatown Lake Reservation in Westchester. “Bald Eagles have rebounded, but we still need to protect their habitat from human development and residual pollution. Birds can get caught and tangled in fishing lines carelessly cut by human fishermen, the woods and waterways still need to be kept clean, there are still threats from mercury, lead and PCBs in the water.” Hudson Valley eagles also face the unique danger that comes from feeding on “train kill.” Many birds have been struck and killed themselves while feeding on the tracks.

Eagles are also extremely sensitive to external stimuli. A train whistle, the rumble of a truck, a boat’s horn will send them flying off. Even if an eagle’s nest is not actually destroyed, the noise and disturbance of human activity or construction on an adjacent lot might be enough to make them abandon the site.

But, they can also be surprising. The birds in Snedens Landing observed by Gottlieb in 2012 abandoned their nest when the lot next to their tree was leveled for construction. It was feared that the eagles were gone for good, but to everyone’s delight, they returned to the nest in the winter of 2013 and actually raised fledglings there that year.

“They know how to adapt,” McGowan remarks. “Their ability to acclimate over time to a changed environment has always been a part of their survival mechanism.”

To raise awareness about the eagles, as well as to respond to increasing public interest, many environmental organizations now offer programs and events both to educate and to celebrate these beautiful birds. The Rockland Audubon Society, the Bedford Audubon Society, The Beacon Institute for Rivers and Estuaries and the New York State Junior Birders Club all hold events and lead eagle watching trips throughout the year. And then there is the annual Hudson River Eaglefest, held by the Teatown Lake Reservation in Westchester. Now in its tenth year, the event will take place on February 8 at the Croton Point Park, with daylong activities, programs, and excursions designed to entertain, educate and raise awareness about the need for continued Bald Eagle support. This year there also will be 10 satellite viewing sites in addition to Croton Point Park, including one at Bear Mountain.

For those who wish to observe the eagles on their own, there are many excellent vantage points in Rockland County to do so. The Stateline Lookout (just south of the border), Piermont Pier, Nyack Beach and Iona Island Sanctuary are good places to start, although Iona is closed to the public during nesting season. The Rockland Audubon Society website contains a list of recommended viewing sites.

There is also one very special Bald Eagle that can be visited at the Bear Mountain Trailside Museums and Zoo. Samantha was one of the original 198 “hacked” birds responsible for the return of Bald Eagles to New York and the Hudson River Valley. Unfortunately, after her release she ranged far into North Carolina where she was shot and permanently lost part of her wing. Because of her identification band, however, her rescuers were able to return her to New York and since 1985 she has lived at the zoo. It is especially fitting for those who love eagles and rejoice in their return to our region to visit Samantha as a way of acknowledging her contribution, along with all of the humans who made it possible, toward one of the most amazing comebacks in American history.