Portrait of South Georgia: Abundance, Exploitation, Recovery

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Sally Poncet first arrived in South Georgia in 1977. At the time, he said, the island beneath Antarctica was just as spectacular as it is today: A nearly 100-mile-long mountain spine defines the terrain; glaciers hang down from the peaks with verdant slopes stretching upward to meet them; shimmering beaches surround the coastline. But in those days, Miss Poncet remembered, there was an empty feeling on the island. “You felt something missing,” she explained. “It wasn’t alive as you knew it could be.”

No one knows South Georgia like Miss Poncet does. As an independent field ecologist, she has researched or counted everything from grasses and albatrosses to elephant seals. His second son was born here on a sailboat in 1979. Now, at 69, he continues to work in the fields as he did 45 years ago.

South Georgia is part of a remote British Overseas Territory with no permanent inhabitants. It is located at the edge of the Southern Ocean, 900 miles northeast of the tip of the Antarctic Peninsula and about 900 miles east of the Falkland Islands.

Its history reads like a list of crimes against nature, including commercial sealing, commercial whaling, and the introduction of non-native species, including mice and caribou.

Now that hunting is a thing of the past and invasive mammals have been destroyed, Ms. Poncet and her colleagues are witnessing a remarkable ecological recovery. The scientific literature offers a muted version of this, but as they listen to scientists driven by data and not inclined to exaggerate, their joy and curiosity arise. Among the terms they use to describe the island’s revival are: “miraculous”, “amazing”, “truly emotional” and “a beacon of hope”.

Of course, nothing is that simple in the age of climate change. But the rebirth of this island can be easily observed. All you have to do is listen.

The first person known to have discovered the island and planted a flag was Captain James Cook in 1775. He described the island as “wild and terrifying,” but also found millions of Antarctic fur seals on the beaches, leading to an island rush. harvest their hides. The sealers arrived in 1786; In the next century, millions of animals were killed, their fur turned into luxury items like top hats. As a result, the fur seal was almost wiped out.

At the same time, hunters killed southern elephant seals, including huge bulls that can reach 8,000 pounds. Their fat was converted into oil, and hunting continued until the 1960s. As both of these species disappeared, their barks and roars also disappeared, and the beaches became increasingly quiet.

Whaling in South Georgia began with Carl Anton Larsen, a Norwegian captain and businessman, who founded a settlement called Grytviken in 1904. Mr. Larsen and his crew killed their first whale on Christmas Eve and had caught 183 whales by the end of that season. , primarily humpbacks, without ever leaving the bay.

Over the next 60 years, a handful of stations on the coast processed 175,250 whales; this figure does not include pelagic factory ships (large ocean liners capable of processing all carcasses entirely on board) that have remained unpunished in the Southern Ocean. This massive harvest critically endangered the blue whale, the largest animal known to ever exist.

When whaling in South Georgia ceased completely in 1965, it also left a largely quiet ocean.

Great human influences continued on land. Mr. Larsen brought reindeer to South Georgia so that whalers could have something to hunt. Even though glaciers acting as natural divides have confined animals to South Georgia’s two peninsulas, their populations still increased steadily, especially after the stations closed. Reindeer trampled the fragile terrain in many places.

Rats and mice also accompanied hunters and whalers. In particular, the rats found abundant bird eggs and chicks to feed on, including those of two endemic species: the South Georgia pintail, a small duck; and the South Georgia pipit, the island’s only songbird. These birds were literally swallowed, and their songs were also lost.

Progressing from such conditions, as Ms. Poncet says, “to an island that returns to its natural rhythm” is in some ways very simple: Leave it alone.

Sealing and whaling largely ceased for commercial reasons; then the apps were banned. The only fur seal count on the entire island took place in 1991, nearly 200 years after the peak of the fur seal era, and was an estimated 1.5 million animals. Today, that number is probably between three and six million and still growing. Southern elephant seals, last studied in the ’90s, are estimated to be stable in 400,000 animals. These populations are coming back on their own; Our role is to stand back and let it happen, including protecting its food sources like krill and squid.

A result of these changes is a soundscape filled with squeaking, barking, burping, groaning, and growling.

“Seals are calling everywhere,” said Miss Poncet. “Continuous – absolutely constant noise.”

Counting whales and understanding their habits can be a challenge, but Jen Jackson, a whale biologist with the British Antarctic Survey, is working on it. Dr. Jackson’s research methods include professional observers, biopsy darts, fecal samples, whale breath droplets, acoustic detectors, and satellite tags. Using historical capture numbers and new scientific data, his team concluded that humpbacks are back to pre-whaling numbers; Of these, 24,500 are in the Scotia Sea surrounding South Georgia.

Blue whale recovery has been much slower, and population estimates as yet undisclosed will be based on photographic identification. But one of the best signs, said Dr. Jackson comes from the sounds he hears underwater. Noting that the whales are almost completely extinct, he said, “There are blue whales looking almost constantly in the underwater environment right now.”

“It just makes my heart sing,” he added. “We’re watching the ocean make itself wild again.”

It took a monumental effort and over $13 million to get rid of the island’s invasive land mammals – reindeer, rats and mice – but the wildlife payoff has been phenomenal. In the summer of 2013, teams that included both Indigenous Sami reindeer herders and Norwegian snipers arrived to wipe out a reindeer population of 6,700 animals. snipers returning in 2014; they were so effective that they only used 11 bullets for every 10 animals they killed. Until 2015, there were no reindeer on the island.

Meanwhile, another effort was underway: the largest rat extermination project in history. Relying on ship support, helicopters, and the expertise of 39 crew members (from logistics to camp cooks), these experts sprinkled 333 tons of specially formulated toxic pellets on every square centimeter of rat habitat and then waited. In the Australian summer, they tracked rat presence (among other things) using peanut butter-stained sticks. The island was declared rat-free in 2018, and the rats are gone too.

The pipits flowed out of the rat-free areas so quickly that the scientists didn’t have time to document their recovery. Since these birds can lay four broods of between three and five eggs a year, their numbers have skyrocketed. Meanwhile, residents of the main British Antarctic Research station found themselves watching large pintail ducks in the harbor during the winter and cleaning figs and pintails from tussac grass in the spring.

“It was like Grytviken being infested with pintails,” said biologist Jamie Coleman, who spent three years in South Georgia. “You could hear them whistling all the time inside the buildings.”

Not all species have experienced the same backlash. Macaroni penguin populations are declining even as king penguin numbers are increasing – in part because the retreat of glaciers has revealed more breeding habitats for king penguins to exploit.

Sei whales are less common than before, and the light-veiled albatross, a magnificent tin bird known as “the spirit of South Georgia” at the call of Miss Poncet, is rapidly disappearing.

Combating the effects on these species, including climate change and associated changes in the ocean, is much more difficult.

Back on the island, Ms. Poncet said she sometimes went out at night to listen to the seabirds. She could hear white-jawed birds and prions this season. “The call is now coming back during the night where it was quiet before,” he said, adding that the bird’s revival was just the beginning of the island’s ecological changes. “Every year I go back and I think wow, how lucky can I be to see it change every year.”

“We can do good things—we are,” he added. “And South Georgia is one such example.”

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