A Shift In Winter Bird Populations Seen As Climate And Habitat Change

From a distance of several hundred yards, all you can clearly see, even with binoculars, is the flush of white from the breast and a speck of black. Then the bird cocks its head down, breaking the surface of the water, tips forward and disappears. Terry Sullivan points at the series of concentric circles that are now expanding across the otherwise smooth surface of Northwest Creek and announces “a diving duck. Could be a loon.”

Several species of waterfowl have now completed their annual migration across the East End, heading to warmer climes. Many of them have taken up residence here, joining several other species that have in the past decade or so, as the climate has changed, decided to winter over, joining the species of other birds that have settled here year-round. And in the colder months, when other entertainment options have thinned or disappeared, birding for seabirds and other transient visitors is never better.

About a hundred yards from the center of the circle, the bird with the white breast surfaces and begins a slow glide across the water. Sullivan points to the knife-thin sliver of wake trailing the bird.

“Yes, that’s how they swim,” he says.

And in profile, as the bird makes its way down the creek in front of us, you can clearly see by the black and white checkered markings on its back, that it’s one of the hundreds of loons that have left their homes in Maine, the Adirondacks or Canada to come and spend the winter with us on the East End.

Sullivan has been an avid birder — one who walks wooded paths, through meadows and across beaches for the purpose of spotting and observing birds in the wild — for nearly three decades. For many of those years, he was a volunteer for the annual Christmas Bird Count, an effort sponsored by the National Audubon Society that attempts to enumerate the birds and various species in the United States each year in a fixed time. This past count began on December 14 and was just completed on January 5. The survey reveals certain trends each year, and Sullivan says he has seen a few changes in the population since he started.

In the woods and fields he is seeing — and hearing — more mockingbirds, a bird that rarely stayed through the winter months, and really wasn’t seen at all in our area up until the 1950s. A medium sized songbird famous for mimicking the songs of other birds, it is mostly pale gray on top and whitish on its belly, with a long tail.

Goldfinches have become more common year-round, and for Sullivan he has noticed them recently attracted to the thistle in his Sag Harbor backyard.

“I hadn’t seen them in their winter plumage,” he said, which goes from “a bright, banana yellow in summer to a more muted gray olive green” when the winter comes.

Also, Sullivan noted, he’s seen a half-dozen yellow-rumped warblers, an unusual visitor to the East End. These are tiny birds with striking yellow markings dotting otherwise gray, black and white feathers.

“And there’s no doubt it’s a yellow-rumped warbler,” Sullivan says. While the bird has the chevron blazes on its wings, which is common among many warblers, it also has a yellow spot on its rump that gives it its name.

And then there’s the tenacious house wren, which has just recently begun wintering over.

The aggressive — if tiny — bird can be extraordinarily territorial. Sullivan tells the story of his wife building two tiny bird houses one year. He watched as a wren family moved into one of the houses. A short time later a sparrow moved into the other. Within days, the wren came over and booted the sparrow out of the house, and then “kicked” the little house apart, picking out all the nesting material the sparrow had brought in, and pecking up the house.

“The house even had tiny rivets in it,” Sullivan laughed.

But while there are changes in the woods and fields, the bigger shift this time of year is along the beaches and the waterways, when shorebirds commence their migration. At least that’s true in most years.

“This year, with such a mild season, was the worst year over the past 30 years for wintering sea ducks,” said Brent Bomkamp, a compiler for the Audubon’s bird count covering the Montauk area, historically one of the most bountiful territories on Long Island for spotting seabirds like scoters, eiders and mergansers.

So, what happened?

“Winter sea ducks are not moving down because the waters aren’t freezing up north,” said Frank Quevedo, executive director of the South Fork Natural History Museum. “We used to have a team that went out and spent a day in Montauk counting all the birds,” said Quevedo, who also participated in this year’s count at Montauk. “Now we can count them in two hours.”

But Quevedo hastened to say that the overall population is not shrinking, it’s just that the birds aren’t moving when the weather is mild.

Migration, he said, is an exhausting endeavor, and estimated that about 50 percent of the birds who do migrate never make it, facing challenges like starvation, hunters, and flying into structures.

“Why would the bird waste that energy and move south if it doesn’t have to?” he asked.

By the same token, the warmer climate also explains why we may be enjoying some species here on a more year-round basis.

“We counted 40 great blue herons last week, they should be gone by now,” said Quevedo. The downside is, however, “if it freezes up and their food source disappears, they’re dead.” One of the largest birds you’ll see in shallow creeks and ponds, they are distinct in their blue-gray plumage, and are easily identifiable in the air with a sleek profile and slender legs trailing behind them.

Nevertheless, triggered by the way light changes with the seasons and thousands of years of evolution, many birds continue their annual migrations and populate local bays, ponds and shorelines.

One positive trend for local birdwatchers is the increasing number of common eiders that have been seen wintering along the shore. The male and the female share a similar profile in that their heads have a distinct slope, from crown to beak. Males are black capped with black and white bodies, while the females are a deep reddish-brown overall with fine black bars.

“It used to be, if you wanted to see an eider, you’d have to go to Montauk,” said Sullivan. But in the past several years, he’s seen them further west, especially in the waterways around Shinnecock.

The species has expanded its breeding range farther south, said Bomkamp, moving into Massachusetts and Rhode Island, and recently have been found breeding on Fisher’s Island.

Among the species Bomkamp recommends birders look out for is the bufflehead, one of the smallest sea ducks in North America, but dramatic looking.

“They’re fairly easy to observe,” said Bomkamp, “with striking black plumage and a white patch.”

They prefer being close to the shore, said Bomkamp, and thus are easier to spot.

Sullivan would agree, and says the local name for bufflehead is “butterball.”

On a walk in the Barcelona Neck Preserve, Sullivan looks over at the bank across Northwest Creek that is golden with reeds and phragmite in the afternoon light, and scans with his binoculars.

“Wading birds are frequently right up there against the bank,” he said, “so they don’t have to come that far out into the water.” Seeing a bright white snowy egret or a heron would not be unusual here.

He gestures across the creek and points out three swans. Then directs my attention to a dark spot several feet to the right, hard against the opposite bank of the creek.

“There’s three birds there. Could be black ducks,” he says.

A small duck flies inches above the water in front of us, but the bird is too fast for Sullivan to get his binoculars on it.

He gets lucky a short time later. A squadron of ducks, spooked by a shotgun blast across the creek, take off low down the length of the creek, out the mouth and into Shelter Island Sound. The birds are no more than a few feet above the surface of the water, a half dozen of them, flying in formation adjacent to each other. He quickly lifts the binoculars up.

“Oldsquaw,” he says. “There’s a lot of white as they’re flying, especially on the males. And they have white heads.”

A term rarely used anymore, oldsquaw was once common when referring to what is now called the long-tailed duck, another over-wintering species Bomkamp suggests birders look out for.

“They have very unique gray, black plumage,” he said. Their long, slender tail feathers curl up in a whisp behind them.

“Another good species to look for is the black-headed gull,” suggests Bomkamp. This is a European species that has recently taken up residence in the Canadian Maritimes, and in recent winters has begun to make its way to the East End. The adult features a very dark brown, almost black, hood that covers most of its face like a mask.

Ocean-goers should look for the tiny sanderlings that are pecking in the sand along the waterline and the purple sandpiper that comes in the winter to feed on algae on rocks and jetties. In the waves they can find a dwindling, but varied number of scoters, said Bomkamp, primarily black, but also white and surf scoters, with their impressive, orange, black and white bulbous bill.

Then there are the raptors.

Winter brings several owl species into the region, including the short-eared owl, long-eared owl and northern saw-whet owl, a small, mottled-brown and white bird with a round head and tufted ears.

Underscoring some of the changes he has seen, Quevedo said, “Short eared owls used to breed here, but because of habitat depletion, they have no habitat left. The EPCAL property [in Riverhead] is one of the last grasslands available for short eared owls, and it’s just enough for them to spend the winter, not establish a year-round location.”

Arguably the star of winter birdwatching — or, as Bomkamp says, the bird that has gotten many people into it — is the snowy owl. This visitor from the Arctic tundra is impressive in its size and its striking coloring.

“For a lot of individuals not used to birding, it’s a great entry bird,” said Bomkamp, who noted their numbers here are on the rise. “They’re so charismatic.”

“They’re relatively easy to spot in open habitat,” said Bomkamp, “and are such a remarkable animal with their buff white coloring and yellow eyes.”

Snowies start arriving in November, said Quevedo, who said at least four of them had been spotted around Shinnecock as of the annual bird count. Indeed, this reporter found one on a recent brisk Sunday afternoon perched in a line of dunes within a mile of the inlet.

“They like the beaches because it reminds them of the tundra,” observed Quevedo.

So, what is it that gets a veteran birder like Sullivan interested?

“For me, it’s being in nature and observing how the birds interact with each other,” said Sullivan.

As if offering an example, at the mouth of Northwest Creek, Sullivan put his binoculars up to look at a black-backed gull sitting on a buoy out a few hundred yards.

“He’s waiting for a diving duck to show up,” said Sullivan.

“Why?”

“To harass him.”

It’s part of the dynamic Sullivan finds compelling in the natural and wild world, which can be territorial, even violent. Three times, he said, he has watched the gulls attack mergansers, roughing them up and stealing their food.

And birdwatchers like Sullivan, Bomkamp and Quevedo are also watching as the long-term effects of a changing world take hold in the avian communities.

While he acknowledges the change in climate and its impact on migratory birds, Bomkamp feels the biggest problem lies elsewhere.

“The greatest threat right now is habitat loss,” he said. “The East End is fortunate because things haven’t changed much, with all the public lands and Gardiner’s Island. But the areas where the birds that we are seeing in migration are coming from, their lands are certainly under pressure.”

“We used to count thousands of different scoters. Now we count them in the hundreds,” said Quevedo. “For me, it’s climate change related. Winters are not as violent, and the birds can sustain their well-being. I don’t think we’re necessarily seeing a depletion in population.”

“But, where it’s taken thousands of years for some of these species to evolve in a relatively stable climate and environment, they are now confronted with a rapidly changing environment,” he said. “But what will the long-term impact be?”