It was not too many years ago that it was questionable if Peregrine Falcons would continue to exist in several locations around the world, including the eastern United States, where it was actually extirpated. It has already been well-reported that the banning of DDT, captive breeding and hacking programs, and careful monitoring of the recovering population have led to a remarkable comeback for Falco peregrinus, to the point where it was removed from the federal endangered species list in 1999. It now nests and remains year-round in locations where one would be hard-pressed to find historical records of its presence, except during migration.
One such location is New York City. Sure, “Duck Hawks” have always migrated through, especially on the coast, and not too far up the Hudson River the birds historically bred on riverside cliffs, but I can only find records of Peregrine Falcons breeding in New York City in one location (the St. Regis Hotel in Manhattan) before they nested on bridges in human-made nest boxes in 1983. Now, according to the New York State Department of Environmental Conservation, which still lists peregrines as endangered in New York State, New York City “has probably the largest urban population of peregrine falcons anywhere, and peregrines nest on every Hudson River bridge south of Albany.”
Of course, Peregrine Falcons are awesome birds and it is certainly better that they exist and persist in the eastern United States then the alternative, but I have to wonder what the presence of year-round Peregrine Falcons is doing to the populations of shorebirds, puddle ducks, and other species that make their way through New York City on migration each year. A recent visit to Jamaica Bay’s East Pond gave me an inkling. When we arrived, the scene was idyllic, with the early morning sun behind clouds creating a colorful pastel reflection on the waters of the muck-laden pond.
As the tide came in and filled the Jamaica Bay basin more and more shorebirds came in to roost at the East Pond, as they do at every high tide. Roosting conserves energy when the birds can’t actively feed, and helps them to fatten up for the next stage of their long migration. It also gives birders like a me a chance to search through the flocks hoping to find rarities. But the shorebirds get no rest and the birders get no chance to sift through the thousands of birds when a Peregrine Falcon is hunting in the area.
Falcons are not, of course, the only reason that shorebirds flush from their roosting spots. Other birds of prey, careless birders and other people, mammalian predators, loud noises, the wind, and seemingly nothing at all can all cause birds to flush, but a “playful” peregrine outdoes them all. And on this particular day the Peregrine Falcon roaming around the East Pond either wasn’t trying very hard to catch prey or it was a really, really, really, lousy hunter. It kept making circuits of the pond putting the shorebirds up into the air and preventing them from roosting and resting. I tried to make lemonade from the lemons the Peregrine Falcon left me with but even the brief look I got of a Hudsonian Godwit when it put down in front of me wasn’t very great. By the time I realized it was there the falcon had flushed it again!
Two days later I was back at Jamaica Bay’s East Pond again, and at least two Peregrine Falcons were still keeping all of the shorebirds jumpy and other birders said that it had been the same in the intervening day. The numbers of dowitchers and sandpipers present was way down from two days earlier, and while the front that passed through was probably irresistible to shorebirds that have a long migration, I think at least some of the decline in numbers came from birds that did not want to refuel in a location loaded with rapacious raptors.
I don’t want anyone to get the wrong idea here. I fully support the protections that Peregrine Falcons have and don’t think that anyone should be trying to shoot them or cull them or catch them or anything like that. I just wonder how much thought went into the possible ramifications of providing Peregrine Falcons nesting platforms that are essentially adjacent to one of the best shorebird spots in the northeastern United States? And how many Peregrine Falcon pairs in New York City are too many? What happens if the falcons take over more Osprey nesting platforms like the one that was used this year? Perhaps it is time to stop providing and maintaining nesting locations and see how the falcons do on their own?
I don’t know the answer to these questions but I think that they need to be asked and answered. And, lest anyone think that I am a straight-up Peregrine Falcon hater I will say that one of the coolest biding experiences I have had in the last year was watching a Peregrine Falcon this past December at Flushing Meadows Park. I was there with my friends Kerry and Becky and we spotted a peregrine coming in over Meadow Lake struggling to carry a pigeon. The gulls went crazy and mobbed the falcon and, eventually, the falcon was forced to drop the pigeon into the lake in order to escape the persecution. The entire event lasted maybe a minute but it felt like an hour of excitement was packed into that one minute. I am sure that the falcon was from one of the bridges that connect Queens to the Bronx, in other words, it is one of the falcons that I think maybe should be left to its own devices to find a nesting spot.
It has been just over thirty years since the reintroduction of Peregrine Falcons in the eastern United States began. Their reintroduction was clearly a success and the major threat to their health, DDT, is no longer a threat considering that it was banned in the United States in 1972. So, the question now is how much energy and how many resources should be focused on continuing to support what is already a vibrant population, perhaps to the detriment of other species that do not get those resources or that may be negatively impacted by the very presence of Peregrine Falcons?