GLOBAL warming may thwart attempts to eradicate rats from the sub-Antarctic island of South Georgia. Glaciers are melting so fast that the rodents will move to new areas before they can be poisoned, with devastating consequences for native birds.
Sailing ships brought rats to South Georgia more than 200 years ago. Since then they have invaded two-thirds of the shoreline, which is covered with tussock grass. When rats move in, they feed on the chicks and eggs of pipits and burrowing seabirds, wiping them out.
This is producing profound changes in the landscape. "The burrowing birds improve soil quality by aeration and nutrient provision, so you can tell the rat-infested areas from the unhealthy look of the grass," says Sally Poncet of the South Georgia Baseline Environment Survey.
Poncet and her colleagues are now trying to eradicate the rats to preserve the island's natural habitat. In small-scale trials, they are ...
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