The Intrepid, Rat-Sniffing Terriers of South Georgia Island
Erik Sörling was doing everything he could to catch a rat. It was 1905, and the assistant taxidermist at the Swedish Museum of Natural History had tagged along with the Swedish Antarctic Expedition on a voyage to South Georgia Island. This rocky, windswept landmass is the largest of a smattering of islands—all now designated British Overseas Territories—in the southern Atlantic Ocean, near the Antarctic Circle. Sörling knew it was plagued by rats. He just couldn’t find them.
He followed their footprints in the mid-April snow, then laid out steel traps baited with fish, fried pork, and chunks of carrots and apples. These enticements weren’t enough, and the traps stayed empty. Weeks passed. When the moon was bright, Sörling ventured out at night with a shotgun. He kept spotting their little prints and tracked them through tufts of tussac grass, but all he found were dead ends—at the foot of a stone heap or at the water’s edge, where he suspected the rats scavenged for food. “I was not lucky enough even to see any,” he recalled.
Conservationists have long been concerned about the rodents scurrying around the island. The brown rats are thought to have landed in the 18th or 19th century, as stowaways on sealing or whaling ships that stopped there. While black rats on some of the neighboring islands have kept to a largely vegetarian diet, their brown cousins on South Georgia have been omnivorous and indiscriminate, chowing down on greenery, insects, and the South Georgia pipit—the world’s southernmost songbird, which doesn’t live anywhere else. Apparently, rats have a thing for them. “The pipit is almost absent wherever rats occur,” noted Robert Headland, a former officer in the British Antarctic Survey.
To give the birds a fighting chance, the South Georgia Heritage Trust kicked off a massive rodent eradication effort in 2011. The $13.5-million project covered roughly 400 square miles of the 1,500-square-mile island, and had the tenor of a military assault—tactics included flinging millions of poisoned pellets from helicopters. (The pellet rain was a late-summer project, to limit the collateral damage to king penguin colonies that lay eggs there from November to April.)