Abundance, Exploitation, Recovery: A Portrait of South Georgia

Abundance, Exploitation, Recovery: A Portrait of South Georgia

Sally Ponsett first came to South Georgia in 1977. Back then, he said, the sub-Antarctic island was as grand as it is today: a spine of mountains, some 100 miles long, defined the terrain; Glaciers are sloping down from the peaks, with lush green slopes rushing to meet them; Glowing beaches are wrapped around the shoreline. But in those days, Ms. Poncet recalled, there was an emptiness in the island. “You felt lacking,” she explained. “It wasn’t as alive as you knew it could be.”

No one knows South Georgia the way Ms. Ponsett does. An independent field ecologist, he has surveyed or counted everything from his grasses and albatrosses to elephant seals. Their second son was born here in 1979 on a sailboat. Now, at 69, she continues to work in the field – just like she did 45 years ago.

South Georgia is part of a remote British Overseas Territory with no permanent population. It is located at the edge of the Southern Ocean about 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 rats and reindeer.

Now that hunting has become history and invasive mammals have been wiped out, Ms Ponsett and her colleagues have seen remarkable ecological improvements. The scientific literature presents a muted version of it, but listening to scientists—who are driven by data and not prone to exaggeration—increases their joy and wonder. Among the words describing the island’s revival: “miraculous,” “brilliant,” “truly emotional,” and “a ray of hope.”

Of course, in the age of climate change, nothing is so easy. But the rebirth of this island is easily seen. All you have to do is listen.

The first person known to explore and flag the island was Captain James Cook in 1775. He called it “wild and terrifying,” but he also found millions of Antarctic fur seals on the beaches, which inspired a crowd. Harvest their skins. Sealers arrived in 1786; Over the next century, millions of animals were killed, their fur turned into luxury items such as top hats. As a result, the fur seal was almost wiped out.

At the same time, poachers killed southern elephant seals, including giant bulls that reached 8,000 pounds. Their blubber was converted to oil, and the hunt continued into the 1960s. As both of these species disappeared, so did their bark and roar – and the beaches became calmer and quieter.

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

Over the next 60 years, a handful of shore-based stations processed 175,250 whales, a figure that does not include ships from the pelagic factory—large ocean-going ships that can process entire carcasses entirely on board. Which operate with impunity throughout the Southern Ocean. This massive harvest left the blue whale, the largest animal ever found, critically endangered.

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

Major human impacts on the land continued. Mr. Larson brought the deer to South Georgia so that the whalers would have something to hunt. While the glaciers, which acted as a natural divide, confined the animals to the two peninsulas of South Georgia, their populations still grew rapidly, especially after the stations closed. In many places, reindeer trampled the fragile landscape.

Along with sealers and whalers, there were also rats and mice. Rats in particular found many bird eggs and chicks to eat, including 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.

Moving from such conditions to, as Ms Poncet put it, “an island returning to its natural rhythm” is in some ways very simple: leave it alone.

Sealing and whaling ended mainly for commercial reasons; Later, the practices were banned. The only all-island fur seal census took place in 1991, nearly 200 years after the peak of the fur seal era, and estimated 1.5 million animals. Today, that number is likely to be between three and six million and is still rising. The southern elephant seal, which was last surveyed in the 90s, is estimated to be stable at 400,000 animals. This population is coming back on its own; Our role is to stand back and let it happen, which includes protecting their food sources like krill and squid.

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

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

Counting whales and understanding their habits can be a daunting task, but whale biologist Jane Jackson of the British Antarctic Survey is working on it. Dr. Jackson’s research methods include professional observers, biopsy darts, stool samples, whale breath droppings, acoustic detectors and satellite tags. Using historical catch counts and new scientific data, his team concludes that humpbacks are back to their pre-whaling numbers; 24,500 of them are in the Scotia Sea, which encircles South Georgia.

Blue whales’ recovery has been very slow, and estimates of their population, which have yet to be released, will be based on photo identification. But one of the best signals, Dr. Jackson said, comes from the sounds she hears underwater. “What you find now in the underwater environment is what blue whales are calling almost constantly,” she said, noting that the whales were almost completely wiped out.

“It just makes my heart sing,” she said. “We’re looking at the ocean again.”

Riding the island of invasive land mammals – reindeer, rats and mice – required a monumental effort and more than $13 million, but the payoff for wildlife has been extraordinary. During the summer of 2013, teams that included both indigenous Sami reindeer herders and Norwegian shooters came together to eradicate the reindeer population of 6,700 animals. Shooter returned in 2014; They were so skilled that for every 10 animals they killed, they used only 11 bullets. As of 2015, the island was free of reindeer.

Meanwhile, another effort was underway: the largest rat eradication project in history. Relying on the expertise of ship supports, helicopters and 39 team members (from logistics to Camp Cook), these experts spray 333 tons of specially formulated poison pellets into every square inch of the rat’s habitat , and then waited. In Australia’s summer, they monitored the rat’s appearance using (among other things) sticks colored with peanut butter. The island was declared rat free in 2018 – and the rats were gone too.

The pipes were inserted so rapidly from rat-free areas that scientists did not have time to document their recovery. Since these birds can lay four clutches of between three and five eggs per year, their numbers swelled in an instant. Meanwhile, occupants at the main British Antarctic Survey Station found themselves flushing pipes and pintails from large rafts of pintail ducks in the harbor during the winter and tussack hay during the spring.

“It was as if Gritwicken was haunted by pintails,” said Jamie Coleman, a biologist who spent three years in South Georgia. “You could hear their whistling in the buildings constantly.”

Not every species has experienced the same rebound. Macaroni penguin populations are declining, even due to an increase in king penguin numbers – in part because glacial retreat reveals more breeding habitat for king penguins to exploit.

Sei whales are still less common than they used to be, and the mild-mannered albatross, a beautiful pewter bird whose calls Ms. Ponsett refers to as the “spirit of South Georgia”, is quickly disappearing.

The impacts on these species, which include climate change and related changes in the ocean, are more difficult to cope with.

Back on the island, Ms Poncet said she sometimes steps outside during the night to listen to sea birds. This season she could hear white-chinned petrels and prions. “Their calls are now coming back through the night to where it was previously silent,” she said, adding that the birds’ revival is just the beginning of the island’s ecological changes. “Every year I come back, I just think, Wow, how lucky I can be to see this change from year to year.”

“We are capable of doing good things – we are,” she said. “And South Georgia is one of those examples.”

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