Sally Poncet first came to South Georgia in 1977. Back then, she said, the sub-Antarctic island was as gorgeous as it is today: A spine of mountains, some 100 miles long, defines the terrain; glaciers drape down from the peaks, with verdant slopes running up to meet them; glistening beaches wrap around the shoreline. But in those days, Ms. Poncet recalled, the island had an empty feel to it. “You felt a lack,” she explained. “It wasn’t alive like you knew it could be.”
Nobody knows South Georgia the way Ms. Poncet does. An independent field ecologist, she has surveyed or counted everything from its grasses and albatrosses to its elephant seals. Her second son was born on a sailboat here in 1979. Now, at the age of 69, she continues to work in the field — just as she did 45 years ago.
One result of these changes is a soundscape replete with squeaking, barking, belching, groaning and growling.
“Seals are calling everywhere,” said Ms. 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. Dr. Jackson’s research methods include professional observers, biopsy darts, fecal samples, droplets of whale breath, acoustic detectors and satellite tags. Using historical catch counts and new scientific data, her team has concluded that humpbacks are back to their pre-whaling numbers; there are 24,500 of them in the Scotia Sea, which surrounds South Georgia.
Ridding the island of the invasive land mammals — reindeer, rats and mice — required a monumental effort and over $13 million, but the payoff for wildlife has been extraordinary. During the summer of 2013, teams that included both Indigenous Sámi reindeer herders and Norwegian marksmen came to eradicate a reindeer population of 6,700 animals. The marksmen returned in 2014; they were so efficient that for every 10 animals they killed, they used just 11 bullets. By 2015, the island was free of reindeer.
The pipits poured in from rat-free areas so fast that scientists didn’t have time to document their recovery. Because these birds can lay four clutches of between three and five eggs per year, their numbers grew in a flash. Meanwhile, those living at the main British Antarctic Survey station found themselves watching large rafts of pintail ducks in the harbor during wintertime, and flushing pipits and pintails from the tussac grass during spring.
“It was like Grytviken was haunted by pintails,” said Jamie Coleman, a biologist who has spent three years on South Georgia. “You could constantly hear their whistling throughout the buildings.”
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