RACHEL MARTIN, HOST:
South Georgia Island is a spectacular spot in the South Atlantic with mountains and glaciers and seabirds and an overabundance of rats. The vermin arrived on whaling ships 200 years ago. And over the decades, they have decimated some of South Georgia's more delicate bird species by attacking their nests.
Last week, a ship headed out from the Falkland Islands with what scientists are hoping is enough poison to finally exterminate the rodents. This is the third phase of a five-year project to put nature back in balance on the island. But it's a tricky proposition in which scientists must spread the poison so it wipes out the rats without killing off the birds at the same time. Apparently, the plan has been working. One expert speaking about a particular bird species told the BBC, quote, "the pipit is our equivalent of a canary in a coal mine. And we are starting to hear their song again."