South Georgia enters the rat race to exterminate its very unwelcome invaders

Helicopters drop 200 tons of poison pellets in world’s biggest extermination project

They call themselves “Team Rat” and yesterday they announced the successful completion of the second phase of the world’s biggest rodent-eradication project to protect the unique sea birds living on the remote island of South Georgia in the South Atlantic.

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Millions of rats and mice introduced to South Georgia by human seafarers over the past 200 years have decimated the ground-nesting birds of the island. Only the 25 men and women of Team Rat stand in the way of the total eradication of the island’s precious bird life, scientists said.

The team have battled appalling weather to lay 200 tons of poisoned pellets from three helicopters flying over sites on the coastal fringes of the island where the rats live. At one stage the project’s scientific director, Professor Tony Martin of Dundee University, thought wind and snow flurries would prevent the completion of the baiting, but a sudden lift in the weather allowed the final pellet to be laid on 18 May, just as the Antarctic winter set in.

“We were forever fighting the weather. It was a race against time – and we almost ran out of time,” said Professor Martin, who has spent most of the past decade planning a way of saving the 31 species of birds that breed on South Georgia, including pipits, petrels and albatrosses.

“I thought in mid-April that we weren’t going to be able to get it done, but I didn’t tell anyone in case it affected morale. But then we got a miracle – eight days of flying weather when at last there was some hope of finishing,” he said.

“We got the job done as the cold weather and snow moved in. We collapsed into our sleeping tents that night with the most amazing sense of relief that we’d got the last pellet out of the last baiting pod”.

The team of international experts from as far as Norway and New Zealand laid the pellets over 580 square kilometres of the UK Overseas Territory, making more than 1,000 flights and clocking up 600 flying hours. About 70 per cent of the work has been completed; the rest will be done in 2015.

South Georgia is criss-crossed with glaciers that divide the island into separate habitable zones for the invasive brown rats, which have no natural predators and feed on the eggs and live young of seabirds that burrow or nest on the ground.

With the glaciers retreating from the coastal areas, rats will soon be able to move freely from one zone to another along new, glacier-free beachheads, making any future extermination programme impracticable, Professor Martin said.

The project is the biggest of its kind ever undertaken on an island where rats have become an invasive species. The poison, which does not dissolve in water and is left untouched by nearly all seabirds, must be spread over entire areas in order to kill as many rats as possible in one go.

The aim is to eliminate entire populations in one season so that not a single breeding pair survives to repopulate the island.

“To clear this magnificent island of rodents accidentally introduced by humans has been an ambition of mine for over a decade and I am thrilled we are well on the way to securing this important seabird habitat for future generations,” Professor Martin said.

It will take at least 10 years to ensure that the island is completely rat-free once the final phase of baiting is finished in 2015. There will always be a chance that a few rats survive the cull, but the longer there are no signs of them, the greater the chances of total success, he said.

As to the ethics of killing one species to protect another, Professor Martin is unapologetic: “The simple fact is that the rats will get to every island in South Georgia and they will eradicate the pipit and other species of birds.

“I feel strongly that humans should put right the damage they have done,” he said.