A portrait of South Georgia: abundance, exploitation, recovery

Sally Poncet first arrived in South Georgia in 1977. At the time, she said, the sub-Antarctic island was as beautiful as it is today: a mountain ridge, about 100 miles long, defines the terrain; glaciers descend from the peaks, with greenish slopes that climb up to meet them; Bright beaches surround the coast. But in those days, Mrs. Poncet recalled, the island had a sense of emptiness. “You felt a lack,” he explained. “He wasn’t alive as you knew he could be.”

No one knows South Georgia as Mrs. Poncet does. An independent field ecologist, he has studied or counted everything from his grasses and albatrosses to his sea elephants. Her second child was born here on a sailboat in 1979. At 69, she continues to work in the field, as she did 45 years ago.

South Georgia is part of a remote British overseas territory with no permanent population. It is located on the shores of the Southern Ocean more than 900 miles northeast of the tip of the Antarctic Peninsula and nearly 900 miles east of the Falkland Islands.

Its history reads as a list of offenses 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, Ms. Poncet and his colleagues are witnessing a remarkable ecological recovery. The scientific literature offers a muted version of it, but when you listen to the scientists, who move through the data and are not prone to hyperbole, their joy and wonder come out. Among the terms they used to describe the island’s renaissance were “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 lining the beaches. which caused a rush to harvest their skins. The stamps arrived in 1786; during the next century, millions of animals were killed, their skin turned into luxury items such as top hats. As a result, the seal was almost removed.

At the same time, hunters killed southern elephant seals, including huge bulls that can reach 8,000 pounds. Its fat turned into oil and hunting continued until the 1960s. As both species became extinct, so did their barking and roaring, and the beaches became 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 this season they had caught 183 whales. , mostly hunchbacks, never leaving the bay.

Over the next 60 years, a handful of coastal stations processed 175,250 whales, a figure that does not include pelagic factory ships, large ocean-going vessels that could process entire carcasses on board, which operated with impunity across the Southern Ocean. This massive harvest left the blue whales, the largest animal ever known, in critical danger of extinction.

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

The main human impacts continued on earth. Mr. Larsen brought reindeer to South Georgia so that the whalers would have something to hunt. Although glaciers, which act as natural partitions, confined animals to two of the South Georgia peninsulas, their populations still grew steadily, especially after the seasons closed. In many places, the reindeer trod the fragile landscape.

Rats and mice also accompanied the seals and whales. Rats, in particular, found many bird eggs and chicks to feed on, including those of two endemic species: the pintail tail of South Georgia, a small duck; and the pipit of South Georgia, the only songbird on the island. These birds were literally swallowed, and their songs disappeared as well.

Moving from these conditions to, as Ms. Poncet, “an island that returns to its own natural rhythm” is somehow very simple: leave it alone.

Sealing and whaling ended largely for commercial reasons; later, internships were banned. The only census of fur seals on all islands took place in 1991, some 200 years after the peak of the seal skin era, and the estimate was 1.5 million animals. Today, that figure is likely to range from three to six million and continues to rise. Southern elephant seals, last surveyed in the 1990s, are estimated to be stable at 400,000 animals. These populations are returning alone; our role is to hold back and let it happen, which includes protecting their food sources such as krill and squid.

One result of these changes is a soundscape full of squeaks, barks, belches, groans and growls.

“Seals are calling everywhere,” Ms. Poncet. “It’s constant, absolutely constant noise.”

Counting whales and understanding their habits can be a daunting task, but Jen Jackson, a whale biologist with the British Antarctic Survey, is working on it. The research methods of Dr. Jackson includes professional observers, biopsy darts, fecal samples, whale breath drops, acoustic detectors, and satellite tags. Using historical catch counts and new scientific data, his team has concluded that humpback whales have returned to their previous numbers in whaling; There are 24,500 in the Scottish Sea, which surrounds South Georgia.

The recovery of the blue whale has been much slower and its population estimate, not yet published, will be based on a photographic identification. But one of the best signs, Dr. Jackson said, comes from the sounds he hears underwater. “What you have in the underwater environment right now is that the blue whales are screaming almost continuously,” he said, noting that the whales were almost completely wiped out.

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

Delivering the island from invasive terrestrial mammals (reindeer, rats, and mice) required a monumental effort and more than $ 13 million, but the benefit to wildlife has been extraordinary. During the summer of 2013, teams including indigenous Sami reindeer herders and Norwegian snipers came to eradicate a reindeer population of 6,700 animals. The shooters returned in 2014; they were so efficient that for every 10 animals they killed, they only used 11 bullets. In 2015, the island was free of reindeer.

Meanwhile, there was another effort underway: the largest rat eradication project in history. With the support of the ship, helicopters and the experience of 39 team members (from logistics to camp cooks), these specialists scattered 333 tons of poison pellets specially formulated for every square inch of habitat. rats and then waited. In the southern summer, they monitored the presence of rats, using (among other things) sticks painted with peanut butter. The island was declared free of rats in 2018, and the mice had also disappeared.

The pipits came out of rat-free areas so quickly that scientists did not have time to document their recovery. Because these birds can lay four to three to five eggs a year, their numbers grew in an instant. Meanwhile, those living in the main station of the British Antarctic Survey found themselves observing large pintail duck ponds in the harbor during the winter, and washing pipits and pintails from the tussock grass during the spring.

“It was as if Grytviken was being chased by pintails,” said Jamie Coleman, a biologist who has spent three years in South Georgia. “You can hear their whistles constantly all over the buildings.”

Not all species have experienced the same rebound. Macaroni penguin populations are plummeting, although the number of king penguins is increasing, in part because glacial retreat reveals more breeding habitat for king penguins to explode.

Sei whales are still less common than before, and the light-capped albatross, a magnificent pond bird whose name Mrs. Poncet refers to as the “soul of South Georgia,” is rapidly disappearing.

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

Back on the island, Ms. Poncet said she sometimes goes out at night to listen to seabirds. This season he could hear white-bearded petrels and prions. “His calls are coming back now during the night where he used to be silent,” he said, adding that the rebirth of birds is just the beginning of the island’s ecological changes. “Every year I come back I just think, wow, how lucky I am to see it change year after year.”

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

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