As the Antarctic Peninsula heats up, the rules of life there are being ripped apart. Alarmed scientists aren’t sure what all the change means for the future.
BY CRAIG WELCH
PHOTOGRAPHS BY PAUL NICKLEN, CRISTINA MITTERMEIER & KEITH LADZINSKI
He was born on a sailboat in Leith Harbour, an abandoned whaling station on South Georgia island. His father, a French adventurer, had met his mother, an Australian zoologist, on a jetty in Tasmania while sailing his boat around the world. The couple started a family in the South Atlantic. For years they traversed the west coast of the Antarctic Peninsula, surveying wildlife in uncharted bays—seals, flowering plants, seabirds—with three boys in tow. Dion was the first.
Click here to see a detailed map of the Antarctic Peninsula and of how climate change is affecting its ice cover.
The Antarctic Peninsula is an 800-mile string of mountains and volcanoes that juts north from the White Continent like the tail on a horseshoe crab. It was Poncet’s playground. Young Dion and his brothers read, drew, and played with Legos—but also chased penguins, lifted chocolate from derelict research stations, and sledded down hills that might never have seen a human footprint. Other kids face schoolyard bullies; Dion was tormented by dive-bombing skuas, which whacked his head hard enough to make him cry. Other kids star in wobbly home movies; the Poncet boys were featured in a 1990 National Geographic film about growing up in the Antarctic. Sometimes, during breaks from homeschooling, Dion’s mom had him count penguins. “It got pretty boring pretty quickly,” he says.
On a frigid evening nearly 30 years later, Poncet and I stood in the wheelhouse of his 87-foot boat, the Hans Hansson, scanning the ice for Adélie penguins. At 39, Poncet is blond, block-jawed, and quiet, with enormous hands. He has spent much of his adult life ferrying scientists and other visitors in charter boats through the waters around South Georgia and Antarctica from his base in the Falklands. Along with a team of photographers led by Paul Nicklen, I had joined him for a voyage along the west coast of the Antarctic Peninsula. We wanted to see how things were changing in a region he’d known his whole life.
Here at the bottom of the world, a place all but free of human settlement, humanity is scrambling one of the ocean’s richest wildernesses. Fossil-fuel burning thousands of miles away is heating up the western peninsula faster than almost anywhere else. (Only the Arctic compares.) The warming is yanking apart the gears of a complex ecological machine, changing what animals eat, where they rest, how they raise their young, even how they interact. At the same time, the shrimplike krill upon which almost all animals here depend for food are being swept up by trawlers from distant nations. They’re being processed into dietary supplements and pharmaceuticals, and fed to salmon in Norwegian fjords and to tropical fish in aquariums.
So much here is changing so fast that scientists can’t predict where it’s all headed. “Something dramatic is under way,” says Heather Lynch, a penguin biologist at Stony Brook University. “It should bother us that we don’t really know what’s going on.”
What we can see is troubling enough. On the western peninsula, Adélie penguin populations have collapsed, some by 90 percent or more. Records of great hordes of the birds in one bay date back to 1904; today in that spot “there are only about six nests left,” Poncet says. That day in the wheelhouse, when Poncet and I spotted our first massive colony, we had left the west for the peninsula’s northeast tip.
On tiny Paulet Island, thousands of penguins were perched in rows up a rocky slope, evenly spaced, like an audience at an opera house. We could see some wandering the remains of an old stone hut built in 1903 by shipwrecked Swedish explorers, who survived a long Antarctic winter by eating penguins. On an iceberg off our starboard beam, a noisy cluster of penguins slipped and knocked about like wobbly bowling pins. When I saw one glissade down polished ice, its flippers pulled back in a skier’s tuck, then tumble into a trio of fellow birds, I laughed out loud. Poncet just nodded.
Antarctica is not all death and chaos: Millions of Adélies still thrive around the continent, performing their unintentional comedy. But the western peninsula’s transformation is profound, and few have seen more of it unfold than Poncet. The world he once knew is unraveling. He speaks of the loss like a farm kid who has watched suburbia gobble the family homestead.
“All the things you used to experience, the places I went when I was a child—I took it for granted then,” Poncet says. “Now you realize it’s not ever going to be possible again.”
Much of Antarctica is a vast plateau, a high desolate desert of blowing snow where temperatures can plunge to minus 140°F. Poncet’s Antarctica isn’t like that at all.
The Antarctic Peninsula is longer than Italy and curls north toward the temperate zone. Its climate—for Antarctica—has always been mild. Summer temperatures often rise above freezing. Isolated patches of vegetation dot exposed granite and basalt. Adélie penguins live all along the coast of Antarctica, but the peninsula also supports species the harsh mainland can’t: fur seals, elephant seals, gentoo and chinstrap penguins. Petrels and sheathbills flit about the skies. All this life relies on the sea.
On the rugged peninsula, Antarctica’s stillness is punctuated by squawking and chattering and concentrated motion. It’s a place of bizarre angles: Blue-white glaciers flow to the ocean and calve into icebergs that assume every form imaginable. Bergs the size of small towns reach into the clouds. Even dozens of miles away, you hear them crack and explode like cannons.
It looks like wilderness, and it is, but it is not untouched. People began altering life in this region decades before anyone had even seen Antarctica. Not long after Capt. James Cook first cut through Antarctic waters in the 1770s, hunters started slaughtering fur seals by the millions, mostly for hats and coats. They also killed elephant seals for oil, to be used in paint and soap. The first to set foot on the continent were probably Connecticut seal hunters who came ashore briefly on the western peninsula in 1821.
In time whalers began harpooning sei whales, blues, fins, and humpbacks. They stripped baleen, or whalebone, from their mouths to make whips, umbrella ribs, corsets, and carriage springs and used the whale oil for heat, lamps, and margarine. In the early 20th century South Georgia became a whaling mecca. Leith Harbour was the last of its stations to close, in 1966.
Climate change has since left an unmistakable mark. Winter air on the western peninsula has warmed more than 10 degrees Fahrenheit since the 1950s. Winds drive changes in ocean circulation that bring warmer deep water toward the surface, helping to reduce sea ice—the broken crust that forms when the ocean’s briny surface freezes. Sea ice now appears later and disappears faster: The ice-free season on the western peninsula lasts a full 90 days longer than in 1979. For a Northern Hemisphere equivalent, imagine summer suddenly stretching to Christmas.
The winter before Poncet was born, his parents spent weeks camping and exploring frozen Marguerite Bay, hauling gear by sledge across its solid surface. “Nowadays,” Poncet says, “that’s finished. Sea ice barely even forms.”
The loss of ice exposes warm water to the cold air, increasing evaporation, which returns to the world’s driest continent as snow—even rain. On a 2016 trip to Marguerite Bay, halfway down the west coast, Poncet faced a deluge that lasted almost a week. “Thirty years ago I don’t think anyone had ever seen a drop of water fall from the sky down there,” he says.
The balmier water pulled from the deep even affects ice on land, by attacking glaciers where they meet the sea as floating shelves. At least 596 of the western peninsula’s 674 glaciers are in retreat, according to a British survey. Elsewhere in Antarctica, far larger ice shelves are thawing and crumbling, threatening a rapid rise in global sea levels. On the east coast of the peninsula itself, ice has been failing spectacularly too—a Delaware-size piece broke off the Larsen C Ice Shelf just last year. But the east coast can still be five degrees Fahrenheit cooler than the west. Prevailing winds often push sea ice from the west around the tip of the peninsula to the east, where a gyre traps it against land.
The western peninsula is Antarctica’s hot spot. Often depicted on maps in white, it’s now so warm that tufts of the continent’s only native flowering plants, hair grass and yellow-flowered pearlwort, are spreading. So are invasive grasses and lichens. Green moss is growing three times as fast as it did in the past. Island peaks once cloaked in snow are now wet and melting, exposing mud or yawning crevasses.
“The landscape is shriveling,” Poncet says.
Hiking recently on the south shore of Elephant Island, off the tip of the peninsula, Poncet was flabbergasted by how temperate things seemed. The weather was humid, the landscape ice free, and enough grass had sprouted that it brought to mind a meadow.
“It didn’t feel like Antarctica at all,” he says.
“NO ONE SAW THIS COMING”
A heavy rain is falling as we depart the Hans Hansson one morning on black rubber rafts, bound for a pebbly shore near the Antarctic Sound, at the northern tip of the peninsula. On a rocky shelf colored like a sunset by streaks of guano, we spy several muddy Adélie penguins. One is a fledgling, whose gray, pillowy down is damp and matted.
Adélies are the peninsula’s only truly Antarctic penguin species. (Chinstraps also live in South America; red-beaked gentoos range from there to Africa.) They build nests of pebbles and return to the same site each year at the same time, even if it’s raining or snowing or ice is melting. They prefer dry rock or soil but now are often forced to build on light snow—only to have nests collapse when the snow melts or fill like ponds when it rains. Adélie eggs are drowning in flooded nests. Drenched and windblown chicks are freezing to death; they lack the moisture-repelling feathers that protect adults.
Adults, meanwhile, struggle with lost sea ice. Adélies molt on floes far at sea and use ice as way stations to avoid predators between hunts. They can swim for days but tend to dive only in the upper few hundred feet of sea. As waters warm, more adaptable penguins are pushing in. Gentoos—fat, tall generalists—are more flexible about when and where they build nests and are more apt to lay new eggs if nesting fails. They hunt closer to land and eat whatever is available. From 1982 to 2017, the number of breeding pairs of Adélies along the western peninsula and South Shetland Islands dropped by more than 70 percent, from 105,000 to 30,000. Gentoo pairs saw a sixfold increase, from 25,000 to 173,000.
Ice is essential to more than just Adélies. It’s as central to this region as grass is to the savanna. When it disappears, relationships can shift unpredictably. One morning near the Antarctic Sound, Nicklen, photographer Keith Ladzinski, and I zip into dry suits and go snorkeling near shore. We watch a skittish Adélie survey the waves from a crumbling raft of ice. The bird seems hesitant to plunge in—with good reason. A leopard seal is circling and occasionally nosing onto the ice.
A leopard seal can weigh half as much as a small car. Its toothy jaws open wider than a grizzly bear’s. When closed, its mouth curves in a mischievous smile. That’s how the predator looks as it corkscrews around us—rakish, impatient, the king of its domain.
Suddenly, two more leopard seals appear. They turn in lazy laps, spiraling one after the other. Soon there are two more, their eyes locked on other penguins. One by one, the birds slip into the water, and the seals give chase. Some penguins turn and scamper back to ice and safety. Others aren’t so lucky. In an area not much bigger than two suburban backyards, five seals are soon feasting on penguins, shaking and shredding their bloody prey.
The show is mesmerizing—and “highly unusual,” Tracey Rogers, a leopard seal expert at the University of New South Wales, later tells me. Leopard seals, like grizzlies, are solitary creatures that usually stake out vast territories offshore. They need ice floes to rest on between hunts. Loss of ice from climate change is leading them to congregate near land, shifting how, where, and even what they hunt.
Leopard seals used to be rarely seen near fur seal breeding grounds. “Some sealers in the 1800s kept meticulous logs and records,” says Doug Krause, a wildlife biologist with the National Oceanic and Atmospheric Administration. “None of them reported seeing leopard seals hanging around.” Now, 60 to 80 leopard seals wriggle ashore every year at Cape Shirreff, in the South Shetlands. At the region’s largest fur-seal breeding ground, they kill more than half the newborn pups.
After commercial sealing stopped in Antarctica in the 1950s, fur seals started making a triumphant comeback. Scientists thought they would adapt well to a warming climate. Now their numbers at Cape Shirreff are declining 10 percent each year. “What we’re seeing is extraordinary,” Krause says. “No one saw this coming.”
HUMPBACKS “GOING BONKERS”
No one foresaw the good news either—the boom in humpback whales.
Starting in the early 20th century, industrial whalers drove most of Antarctica’s cetaceans nearly to extinction, and many species are still struggling. Blue whales, for example, are thought to have numbered about a quarter of a million around 1900; the population today is 5 percent of that. But Antarctic humpbacks are roaring back: Their population is rising by 7 to 10 percent a year. “They’re going bonkers!” Ari Friedlaender shouts as we dart across the water in an open skiff in the Palmer Archipelago, where we rendezvoused with him.
Friedlaender, a marine ecologist with the University of California at Santa Cruz and a National Geographic explorer, has been studying humpbacks off Antarctica since 2001, tracking how and where they move and feed. He has recorded them rolling and playing with one another and diving deeper than anyone expected. He’s seen them opening gashes in ice with their blowholes. For animals that can weigh up to 40 tons, all this requires a lot of energy—and for now, he says, climate change is making more fuel available.
Friedlaender saw his first sign of that on a cruise in May 2009. It was late fall, so he and his colleagues assumed the humpbacks would have long since left for their wintering grounds near Ecuador and Panama. Then an echo-sounder detected a blob of krill that spread for miles below the ship. “We woke the next day, and there were more whales than any of us had ever seen at any time, at any place on the planet,” says Friedlaender, who has also studied them off Alaska, California, and New England. They counted 306 humpbacks in a 10-mile stretch. “They were here because there was no ice.”
Humpbacks, he explains, used to leave Antarctica in late March or early April, when sea ice closed in. Now they have many more ice-free weeks with more open water in which to roam widely and feed on krill. Those beady-eyed, translucent creatures are the size of a child’s pinkie, but they travel in thick swarms that can stretch for miles, with 78,000 or more in a single cubic yard. Humpbacks are sticking around and fattening up on krill, and that’s fueling a population boom. Female whales are producing calves every year. Lactating mothers have so much strength they’re feeding newborns while pregnant. “That’s insane for an animal that big,” Friedlaender says.
He pulls alongside a humpback and her calf, resting in brash ice. The skiff bobs as Friedlaender, like some ponytailed modern harpooner, raises a long shaft above his head. The business end holds a waterproof camera fitted with suction cups. Friedlaender steadies his quivering weapon, takes aim, then slaps the camera on the leviathan’s back. The surprised whale makes a sound like a wet snore. Both mother and calf dive.
“Felt like a great stick!” Friedlaender yells. For a day or two, until it falls off and floats to the surface to be retrieved, the camera will record a whale’s-eye view of the sea. Humpbacks fare far and deep with few natural competitors. But how well they fare now depends on us.
EVERYBODY LIKES KRILL
A few years ago, an icebreaker dragged research nets around the Palmer Archipelago, looking for Antarctic silverfish—oily, sardinelike creatures that spawn beneath sea ice. They used to be the dominant fish off the western peninsula, composing half of what some Adélie penguins ate. But the team, led by Joseph Torres of the University of South Florida, towed day and night around Anvers and Renaud Islands and never caught a single silverfish. In waters that have experienced some of the greatest sea-ice declines, the fish had all but disappeared. Meanwhile scientists noticed penguins gulping more krill—even though it can take 20 krill to match the caloric value of one silverfish.
Will there be enough krill to go around? It’s not an easy question. Penguins and humpbacks eat krill, but so do skuas, squid, fur seals, and crabeater seals. Leopard seals sometimes eat krill. A blue whale eats millions a day. Animals that don’t eat krill often feed on prey that does. Antarctica loves fatty krill. So do we.
In the 1960s, seeing a potential new seafood source, Soviet fleets began circling the continent. Today about 10 ships a year catch krill, led by Norway, South Korea, China, Chile, and Ukraine. The catch turns up in omega-3 pills and chewable krill-oil gummies and farmed salmon. In Ukraine peeled krill is sold in tins, like sardines. Sometimes krill gets processed at sea, boiled and dried into powder on huge trawlers.
After almost a month at sea we finally see one, in the Bransfield Strait, off the South Shetlands. A storm rocks the 333-foot Long Da, a Chinese mid-water factory trawler, as we pull along her stern. The boat’s net courses through the water like a gape-mouthed whale shark. As the crew haul it in, the net’s green mesh curls over itself, cocooning millions of krill.
For now, krill around Antarctica remain abundant. Trawlers net only a tiny fraction of the continent’s krill. Fishing is tightly managed by 24 countries and the European Union, organized as the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). But krill populations are cyclical, and researchers can’t say how quickly or severely warming and loss of ice may affect them. “We measure krill and may think we understand it, but we don’t, really,” says Christian Reiss of NOAA Fisheries.
Many experts worry that krill boats could target and deplete krill on feeding grounds important for other wildlife. A team of U.S. government scientists in 2017 put it bluntly: “If predators and the fishery use the same population of krill, it follows that removal of krill by one group may limit the availability to the other.” Most fishing takes place where climate change has stressed animals the most—near the western peninsula. “Where is there also one of the greatest densities of predators?” Friedlaender asks. “Same place.”
NATIONAL GEOGRAPHIC 360
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In 2017 Chile and Argentina proposed that CCAMLR place thousands of square miles west and north of the peninsula off-limits to krill fishing. Just this summer, environmental groups and Norway’s AkerBioMarine, the largest krill-fishing company in the world, helped persuade most others in the krill industry to avoid fishing near penguin colonies during breeding periods next year. Starting in 2020, the companies say, they will stay at least 30 kilometers, or 19 miles, from penguin colonies year-round.
Many scientists and wildlife advocates maintain that permanent no-fishing zones regulated by CCAMLR are the safest solution. Otherwise, says Kim Bernard, an Oregon State University oceanographer who studies krill, “things could go very badly here. That really scares me.”
GOODBYE HANS HANSSON
One evening on the Hans Hansson, after a dinner of lamb and potatoes, Poncet traces a map in the galley, pointing out places he once chased krill with a butterfly net. It was common when he was a child to see massive swarms at the surface, he says. “Sometimes the engine would overheat because the water intakes were blocked with krill,” Poncet recalls. Today “you almost never see them” in those places.
Scientists take Poncet’s long experience seriously. “In a way, it’s traditional knowledge,” Bernard says. As Antarctica hurtles toward the unknown, scientific knowledge is still sparse.
This year Poncet abruptly sold the Hans Hansson. He says he and his companion, Juliet Hennequin—also an accomplished boat captain—were exhausted. But he also felt that too many visitors took the region’s bounty for granted, just as it was changing into a place he barely recognized. “When I take stock of the current situation, the Antarctic Peninsula I knew as a child has already largely gone,” he says. “I do wonder a lot what it will become.”
Source : https://www.nationalgeographic.com/magazine/2018/11/antarctica-climate-change-western-peninsula-ice-melt-krill-penguin-leopard-seal/
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