Climate change takes hold in North Carolina’s ghost forests

“Ghost forests” are found throughout the Alligator River National Wildlife Refuge near Port Mans, North Carolina. The salty water of the rising seas pollutes the fresh water on which the trees depend, poisoning and slowly killing them. 

ALLIGATOR RIVER NATIONAL WILDLIFE REFUGE, NC – As the first light flashes through the Croatian sound, Scott Lanier scans the barren gray tree trunks that stand in every direction, like the massive tombstones that mark the once vibrant landscape.

“The forest is just retreating,” says Lanier, director of this 160,000-acre federal wildlife refuge near Outer Banks, North Carolina.

Lanier came here to work for the US Fish and Wildlife Service in the mid-1980s and stayed for several years before heading to jobs in the Southeast. When he returned in 2006, one question resounded in his mind as he walked around:

“What happened to the trees?”

The astonishing transformation he witnessed then has only accelerated in recent years. “You have changed so much, and you have changed so quickly,” he says.

Few examples of climate change are so unmistakable and deadly as the “ghost forests” that spread along parts of the East Coast – especially throughout the Albemarle Peninsula – Pamlico in North Carolina.

The places where Lanier once stood on dry land are now in deep water. Forests populated with towering pines, red maples, sweet gum, and bald cypress have turned into shrublands. Stretched shrubland habitats gave way to marshes. And what was once a swamp has succumbed to the encroaching sea.

As sea levels rise, droughts deepen and storm surges intensify, salt water makes its way into these forests more easily than surrounding water bodies, as well as deep into the sprawling network of drainage and irrigation canals that were created long ago to support the expansion of agriculture.

Constantly wet conditions can weaken existing trees. And episodes of saltwater intrusion can push already stressed forests to breaking point, poisoning the freshwater on which they depend and hastening the death of trees not only at the water’s edge, but in some cases far inland. The result is swaths of dead or dying trees, known as ‘obstacles’, which stand as the grim relics of a shifting ecosystem.

“This has happened over and over again in geologic time,” says Marcelo Ardon, an ecologist at North Carolina State University. “But now it’s happening faster.”

Ghost forests have been around for decades. But as they proliferate, scientists are racing to better understand the drivers of changes, what humans might do to slow the demise of such forests and what the consequences lie in store for them if the trend continues.

They are investigating what profound changes in coastal systems might mean for the migratory birds, mammals, reptiles and plants that call them home.

And they worry about what will happen from the vast carbon stores these landscapes hold, huge amounts of which could be released back into the atmosphere as forests die and land recedes — a shift that could further complicate efforts to slow the planet’s warming. .

“I still feel like we’re just scratching the surface and trying to figure out what the impact is, how big the area is,” Ardon says.

‘Something is wrong’

Emily Yurey was haunted by what she saw when she began traveling through the coastal stretches of North Carolina, where the gray skeletons of trees were spread out in places as far as she could see.

“You just know by looking at something is not right,” said Yuri, who at the time was a doctoral student at Duke University, studying wetland ecology. “Most of the basic questions were not answered,” she added. Where does this happen? Why does this happen? To what extent does this happen? “

To help answer this last question, Urey and other researchers turned to Google Earth, examining visible changes over the past 35 years in the Alligator River National Wildlife Refuge.

at A paper published last year, they found that despite its protected status, nearly a third of the refuge—or more than 47,000 acres—had converted from a forest habitat to either shrubs or swamps during that time. Another nearly 3,000 acres “lost at sea”. Up to 11 percent of the refuge has become a ghost forest, dominated by dead trees and fallen logs.

While the largest forest losses occurred where the refuge met the Croatian and Palliko bass, the researchers note, tree death “also occurred in low-elevation inland areas and along the main channels”.

Certain events clearly played a role. For example, researchers noted a sudden rise in deaths after Hurricane Irene in 2011 pushed massive amounts of salt water into forests already stressed by years of drought. But the problem persisted in the years that followed.

In their findings, Urey and her colleagues saw a glimpse of what lies ahead in regions just outside this corner of North Carolina, where sea levels have risen. almost feet during the last century. scary phenomenon have unfolded Along the Atlantic coast, from the swamps of Louisiana to the Chesapeake Bay, from the white cedar forests of New Jersey to the mouth of the Saint Lawrence River in Canada.

They wrote that “these unprecedented rates of deforestation and land cover change due to climate change may become the status quo for coastal areas around the world, with implications for wetland function, wildlife habitat, and the global carbon cycle.”

Ori knows that many people may not be aware of the long-term threats their transformation poses, even with stricken trees hard to see. Saltwater intrusion causes damage in more immediate and visceral ways, such as Pollution of aquifers and the contamination of agricultural lands that were fertile in the region.

But the less obvious changes are significant.

“People don’t really care about swamp forests. They’re not really inhabited,” said Urey, a postdoctoral fellow at the University of Waterloo in Ontario. “But they are seeing this massive shift, a loss of an underappreciated but still very valuable ecosystem. for water quality, wildlife habitats, and carbon storage.”

“And it’s definitely a canary in a coal mine for coastal change.”

On a sun-soaked spring morning, the ecologist, Ardon, is knee-deep in the cool waters in the sound of Albemarle.

“It’s happening here,” he says of climate change. He nodded toward the fallen tree trunks jutting out of the water, some 50 or more feet from shore. “Maybe that land was 20 years ago.”

After a short walk on land, Ardón has arrived at one of the many test sites that he and his colleagues maintain within the Palmetto-Peartree Reserve. And year after year, they keep track of whether the soil is piling up or sagging.

In this spot, as in others, the forest floor is adding mass one millimeter at a time, but at a much slower pace than the local rate of sea level rise.

Ardon calls it “bad math”. “Over time, the sound will swallow up these forests.”

The move from forested wetlands to swamps, and eventually to open water, scientists say, raises daunting questions about what will happen to the habitats of a range of species, including red woodpeckers and many other birds, black bears, river otters and threatened red wolves. with extinction. .

It also has serious implications for climate change.

The researchers found An estimated 27 million tons of carbon are stored in trees and other biomass along the Albemarle-Pamlico Peninsula.

a Study 2020 It details how ghost forests infiltrated nearly 15 percent of the region’s unmanaged public lands from 2001 to 2014. During that time, the authors said, changes allowed an estimated 130,000 tons of carbon to escape into the atmosphere that was from He would still be detained otherwise. These emissions are increasing the temperature of the planet and making it difficult to avoid disasters in the future.

a A separate study last year It found that “the amount of carbon lost from dying forests is much greater than that gained by growing marsh soils.” The time it would take for wetlands to compensate for the carbon-related impact of dying trees, the authors wrote, “is on the scale of centuries, roughly the same amount of time as would be expected for swamps to submerge due to rising sea levels.”

In other words, more evidence of bad math.

“If you were to lose this forest and all that carbon above ground, how long would it take the swamps to recover the lost carbon? It’s in the range of 200 to 600 years,” Ardon says.

Neither swamps nor humans have that kind of time to fend off climate change, he said, as he surveys the forest and the creeping shoreline beyond.

“At that time, this will be underwater.”

Trying to slow down is inevitable

researchers from Florida to New Jersey And from Louisiana to Maryland Busy trying to learn more about the causes and consequences of ghost forests – from the effect they have on wildlife and water quality to whether trees are dead emit greenhouse gases through their straw-like trunks.

Meanwhile, state and federal wildlife officials, along with groups like the Nature Conservancy, are trying to slow the rapid transformation, even knowing the land may not be what it once was.

In North Carolina, this meant that a file group of efforts Such as planting oyster reefs to combat erosion, planting more saltwater-tolerant plants and trees, and engineering specialized drainage trenches aimed at preventing saltwater from penetrating deeper into the forest and remaining vegetation.

“If we don’t do something, the forest could quickly collapse and go from being woodland to open water,” said Brian Botin, director of the Albemarle-Pamlico Sounds Program at the Nature Conservancy. “We’re buying time to let it transition into something that’s still functional and still provides a home for a variety of species.”

But the future is fraught with peril for these landscapes and others like them, as researchers He wrote in one study last summer: “At the current rate of deforestation, in the absence of large-scale conservation or restoration efforts, moist coastal forests may not persist into the next century.”

Even as scientists continue to study the problem, says Emily Bernhardt, a Duke ecologist and professor and co-author of that and other study on ghost forests, they should help policymakers, farmers, and other residents think about how to make the most of the contracts to come.

Scientists have documented the changes that have already occurred and those that are likely to come. The question is, can we go there in a smart and intentional way that protects livelihoods and biodiversity? Or are we going there in a very disastrous way? “

They are questions Lanier often asks as he approaches home ground in his career.

As director of the Alligator River National Wildlife Refuge, the vast majority of which lie barely two feet above sea level, he knows that a person in his job can encounter “something completely different” in just a few decades. If current trends continue, he said, the majority of the refuge could be under water within a century.

“It’s troubling to see a landscape that you’re trying to manage for the sake of wildlife extinction,” he said.

But Lanier and others who take an interest in this place are not content to sit idly by. There is wildlife that depends on this habitat, humans who rely on the benefits of water purification and a planet that depends in part on its ability to store carbon.

“We’re trying to figure out what we can do to make sure the place is as flexible as possible,” he said. “To try to slow down the change for as long as possible.”