Fire Island Has Gone to the Cats

In New York’s only federal wilderness area, the loss of a key predator has led to the rise of a new one—with dire consequences for the island’s native birds.

Story by Ramin Skibba

On New York’s Fire Island, a small, sand-colored shorebird called the piping plover is fighting for survival after a scourge of feral felines took over its island home. 

Long and narrow, at only half a kilometer (0.3 miles) wide, Fire Island runs parallel to the southern coast of Long Island, New York, and helps buffer inland areas from the full brunt of the sea. Fire Island is connected to the larger landmass by a pair of bridges, and the island’s beaches and wilderness, including its rare forest of American holly trees, draw numerous tourists every year.

“We have the only federally designated wilderness area in the state of New York,” says Jordan Raphael, a National Park Service ranger and biologist on Fire Island. “We have unique habitats that are relatively pristine, and you have this island that’s so close to New York City. It’s really one of a kind.”  

Despite this, Fire Island’s piping plovers (Charadrius melodus) have had a rough couple decades. In the 2010s, the species was struggling from the impacts of increased tourism development and a series of storms; only 20-something nesting pairs remained on the island. The birds largely escaped the wrath of 2012’s Superstorm Sandy, even though the storm literally cut their island home into pieces. But even that already precarious existence took an unexpected turn in 2015 when the birds’ top predators—red foxes—were hit by a highly contagious skin disease called sarcoptic mange. 

Also known as canine scabies, this nasty mite-borne disease is often lethal for wild canids. Because piping plovers nest on the ground, foxes often go after their eggs and their chicks, which Raphael describes as cotton balls on toothpicks. “I don’t want to say we celebrated the decline of the fox population, but we saw the benefit of that for the piping plover population,” Raphael says.

Yet what might have been a boon for the birds instead kicked off a cascade of ecosystem changes with dire consequences. Christy Wails, a wildlife researcher at Virginia Tech, tracked this transformation as it unfolded.

Using a network of trail cameras, Wails and her colleagues watched how the island’s ecosystem has evolved over the past decade, and how other predatory species, such as raccoons and opossums, responded to the sudden dearth of foxes. Ultimately, they found that feral cats were quick to fill the void, as they do in other places where there is a sudden power vacuum caused by the loss of top predators. And now, Wails says, piping plovers are being lost to the claws of cats at a rate that far exceeds what they suffered in the island’s fox era.

So now people have to figure out what to do with all those cats. 

Wails says the cats probably migrated to the island by multiple means. Some may have strolled across the bridges that connect Fire Island to Long Island, while others possibly crossed in winter when parts of a nearby bay froze over. Or maybe they swam across. But the most likely explanation, Wails says, is that people brought cats to the island that then escaped into the wild and spread.

While conducting surveys on Fire Island, Wails and her team encountered cats that had had their ear tips removed. Animal control officers commonly snip a cat’s ear after its been part of a trap, neuter, and release (TNR) program. TNR programs help limit feral cat populations, but Wails says that effort alone won’t be enough to solve Fire Island’s cat problem.

“There’s a lot of evidence to suggest that TNR operations don’t fully prevent cats from going elsewhere; they don’t prevent the spread of diseases; and they don’t entirely prevent breeding” in the population, she says, since it’s logistically and financially impossible to catch every single cat and kitten. Plus, operating a TNR on federally protected parkland is prohibited. Realistically, Wails says, the cats have to be removed.

Raphael and the National Park Service, meanwhile, are trying their best to keep the feral cats out of Fire Island’s prime wilderness areas while focusing on bolstering plover habitat. The birds benefit most when they can access open, sparsely vegetated dunes, as that gives them a good vantage to detect predators and people who might accidentally disturb their nests.

Visitors to Fire Island might not even notice piping plovers. Small and well camouflaged, these birds blend easily into the shoreline scenery. But ecologists, conservationists, and land managers all agree on their importance. “For these beach-nesting shorebirds, their presence … signifies the health of [the] ecosystem,” says Michelle Stantial, a quantitative ecologist at the U.S.-based Four Peaks Environmental Science and Data Solutions who has studied the piping plover population in nearby New Jersey.

“And when we have these spaces to visit that are functioning the way that they’re supposed to,” she says, “that is good for humans, too.”

https://www.biographic.com/fire-island-has-gone-to-the-cats/