Rising Seas Endanger Wetland Wildlife

For scientists in a remote corner of coastal North Carolina, ignoring global warming is not an option

Brian Boutin, a Nature Conservancy biologist, stands protectively over a newly planted bald cypress sapling. Park managers hope to slow the submersion of the Alligator River National Wildlife Refuge. (Lynda Richardson)
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When a buttermilk moon rises over Alligator River, listen for red wolves. It’s the only spot in the world where they still howl in the wild. Finer boned than gray wolves, with foxier coloring and a floating gait, they once roamed North America from the Great Lakes to the Gulf of Mexico. By the mid-1970s, because of overhunting and habitat loss, just a few survived. Biologists captured 17 and bred them in captivity, and in 1987 released four pairs in North Carolina’s Alligator River National Wildlife Refuge.

Today more than 100 red wolves inhabit the refuge and the surrounding peninsula—the world’s first successful wolf reintroduction, eight years ahead of the better-known gray wolf project in Yellowstone National Park. The densely vegetated Carolina refuge is perfect for red wolves: full of prey such as white-tailed deer and raccoons and practically devoid of people.

Perfect, except it may all be underwater soon.

Coastal North Carolina is more vulnerable than almost anywhere else in the United States to sea-level rise associated with climate change, and the 154,000-acre Alligator River refuge could be one of the first areas to go under. A stone’s throw from Roanoke Island, where the first English colony in North America was established in the 1580s, it’s a vibrant green mosaic of forest, piney swamp and salt marsh. I’ve seen a ten-foot alligator dreaming on a raft of weeds, hundreds of swallowtail butterflies rising up in giddy yellow spirals and scores of sunbathing turtles. The refuge has one of the highest concentrations of black bears on the East Coast. It is home to bobcats and otter and a haven for birds, from great blue herons to warblers to tundra swans. Most of it lies only about a foot above sea level.

Scientists at Alligator River are now engaged in a pioneering effort to help the ecosystem survive. Their idea is to help shift the entire habitat—shrubby bogs, red wolves, bears and all—gradually inland, while using simple wetland-restoration techniques to guard against higher tides and catastrophic storms. At a time when many coastal U.S. communities are paralyzed by debate and hard choices, such decisive action is unusual, if not unique.

“We’re on the front line here,” says Brian Boutin, a Nature Conservancy biologist leading the Alligator River adaptation project. “We’re going to fight [sea-level rise] regardless. But it matters whether we fight smart or fight dumb.”

Sea level has been increasing since the peak of the last ice age 20,000 years ago, when the glaciers began melting. The rise happens in fits and starts; in the Middle Ages, for instance, a 300-year warming period sped it up slightly; starting in the 1600s, the “Little Ice Age” slowed it down for centuries. But scientists believe that the rate of rise was essentially the same for several thousand years: about one millimeter per year.

Since the Industrial Revolution, however, the burning of fossil fuels has increased the amount of carbon dioxide and other gases in the atmosphere, which trap the earth’s reflected heat—the now familiar scenario called the greenhouse effect, the cause of global warming. The rate of sea-level rise around the world has tripled over the past century to an average of about three millimeters a year, just over a tenth of an inch, because of both melting glaciers and the expansion of water as it warms.

In 2007, the Intergovernmental Panel on Climate Change predicted seven inches to two feet of global sea-level rise by 2100. Some scientists, however, think it will be more like six feet. Such wildly varying predictions are the result of huge unknowns. How much of the gargantuan ice sheets in Greenland and West Antarctica will melt? How will human populations affect greenhouse gas emissions? Will ocean currents change? Will the water rise steadily or in spurts?

Making matters worse, the mid-Atlantic region lies on a section of the earth’s crust that is sinking one or two millimeters a year. In the last ice age, the continental plate on which the region sits bulged upward like a balloon as massive glaciers weighed down the plate’s other end, in what is now the Great Lakes region. Ever since the glaciers began to melt, the mid-Atlantic has been falling back into place. The inexorable drop compounds the effects of sea-level rise.


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