A Portrait of South Georgia: Abundance, Exploration, Recovery

Sally Poncet first came to South Georgia in 1977. Back then, she said, the sub-Antarctic island was as beautiful as it is today: a column of mountains, some 100 miles long, defines the terrain; glaciers descend from the peaks, with verdant slopes rising to meet them; gleaming beaches envelop the coast. But in those days, Poncet recalled, the island had a feeling of emptiness. “You missed it,” she explained. “It wasn’t alive like you knew it could be.”

Nobody knows South Georgia like Mrs. Poncet. An independent field ecologist, she has researched or counted everything from grasses and albatrosses to elephant seals. Her first child was born on a sailboat here in 1979. Now, at 69, she continues to work in the fields – just as she did 45 years ago.

South Georgia is part of a remote British Overseas Territory with no permanent population. It sits on the edge of the Southern Ocean, over 900 miles northeast of the tip of the Antarctic Peninsula and nearly 900 miles east of the Falkland Islands.

His story reads like a list of crimes against nature, including commercial seals, commercial whaling and the introduction of non-native species including rats and reindeer.

Now that hunting is history and invasive mammals have been eradicated, Poncet and his colleagues are witnessing a remarkable ecological recovery. The scientific literature offers a silent version of this, but when listening to scientists – who are data-driven and not prone to hyperbole – their joy and wonder comes to the fore. Among the terms they used to describe the island’s rebirth: “miraculous”, “spectacular”, “really emotional” and “a beacon of hope”.

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

The first known person to explore the island – and plant a flag – was Captain James Cook in 1775. He called it “wild and horrible”, but he also found millions of Antarctic seals on beaches, which led to a race. to harvest their skins. The seals arrived in 1786; in the following century, millions of animals were killed, their skins turned into luxury items such as top hats. As a result, the seal was nearly wiped out.

At the same time, poachers killed southern elephant seals, including the massive bulls that can reach 8,000 pounds. Their blubber was converted to oil and hunting continued into the 1960s. As these two species disappeared, so did their barking and roaring – and the beaches grew quieter and quieter.

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

Over the next 60 years, a handful of shore stations processed 175,250 whales, a number that doesn’t include the pelagic factory ships — large ocean-going ships that could process entire carcasses entirely on board — that operated with impunity across the Southern Ocean. This massive harvest has left blue whales, the largest animal ever known, critically endangered.

When South Georgia whaling ended for good in 1965, it also left behind a largely silent ocean.

Major human impacts continued on land. Mr. Larsen brought reindeer to South Georgia so the whalers would have something to hunt. While glaciers, which act as natural dividers, confined the animals to two South Georgia peninsulas, their populations still grew steadily, especially after the seasons closed. In many places, reindeer trampled the fragile landscape.

Rats and mice also accompanied seal hunters and whalers. The mice, in particular, found plenty of 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 up – and their songs disappeared too.

Progressing from such conditions to, as Poncet said, “an island that is returning to its own natural rhythm” is, in some ways, very simple: leave it alone.

Seal and whale hunting ended largely for commercial reasons; later the practices were banned. The only fur seal census of all the islands took place in 1991, about 200 years after the peak of the seal era, and the estimate was 1.5 million animals. Today, that number is likely between three and six million and still rising. Southern elephant seals, last surveyed in the 1990s, are estimated to number 400,000 animals. These populations are returning on their own; our role is to step back and let it happen, which includes protecting your food sources like krill and squid.

One result of these changes is a soundscape filled with squeaks, barks, burps, groans and growls.

“The seals are calling everywhere,” said Poncet., “it’s constant – absolutely constant noise.”

Counting whales and understanding their habits can be an arduous task, but Jen Jackson, a whale biologist with the British Antarctic Survey, is working on it. The research methods of Dr. Jackson include professional observers, biopsy darts, fecal samples, whale breath droplets, acoustic detectors and satellite tags. Using historical catch counts and new scientific data, her team concluded that humpbacks have returned to pre-whaling numbers; there are 24,500 of them in the Sea of ​​Scotland, which surrounds South Georgia.

The blue whale’s recovery has been much slower, and its as-yet-unreleased population estimate will be based on photo identification. But one of the best signs, Jackson said, comes from the sounds she hears underwater. “What you have in the underwater environment now is blue whales calling almost continuously,” she said, noting that the whales were almost entirely wiped out.

“It just makes my heart sing,” he added. “We are seeing the ocean reorganize itself.”

Ridding the island of invasive land mammals – reindeer, rats and mice – took a monumental effort and more than $13 million, but the payoff for the wildlife was extraordinary. During the summer of 2013, teams that included indigenous Sámi reindeer herders and Norwegian sharpshooters came to eradicate a reindeer population of 6,700 animals. Shooters returned in 2014; they were so efficient that for every 10 animals they killed, they used only 11 bullets. In 2015, the island was reindeer-free.

Meanwhile, another effort was underway: the largest rat eradication project in history. Relying on the support of the ship, helicopters and the expertise of 39 team members (from logisticians to camp cooks), these experts sprinkled 333 tons of specially formulated poison pellets into every square inch of the rats’ habitat and waited. In the southern summer, they monitored the presence of mice, using (among other things) sticks painted with peanut butter. The island was declared rat-free in 2018 – and the mice disappeared too.

The pipits came from rat-free areas so fast that scientists didn’t have time to document their recovery. As these birds can lay four broods of three to five eggs a year, their numbers quickly grew. Meanwhile, those living in the British Antarctic Survey main station found themselves watching large rafts of pintail ducks in the harbor during the winter, and releasing pike and pintail from the tussac grass during the spring.

“It was like Grytviken was haunted by pintails,” said Jamie Coleman, a biologist who spent three years in South Georgia. “You could constantly hear their whistles through the buildings.”

Not all species experienced the same rebound. Macaroni penguin populations are plummeting, even as king penguin numbers increase — in part because glacial retreat reveals more breeding habitat for king penguins to explore.

Sei whales are still less common than they used to be, and the light-mantle albatross, a beautiful pewter bird whose name Poncet refers to as the “soul of South Georgia,” is rapidly disappearing.

The impacts on these species, including climate change and associated changes in the ocean, are much more difficult to address.

Back on the island, Poncet said he sometimes goes out at night to listen to the seabirds. This season, she could hear white-chinned petrels and prions. “Your calls are now returning during the night where it was silent before,” she said, adding that the bird revival is just the beginning of the island’s ecological changes. “Every year I come back, I just think, wow, how lucky can I be to see this change year after year.”

“We are capable of doing good things – we are,” she added. “And South Georgia is one such example.”

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