A REMOTE wildlife-rich island has been officially declared free of rats and mice after a £10 million Scots-based eradication scheme to protect native birds.

The UK overseas territory of South Georgia is now free of invasive rodents that have been arriving as stowaways since Captain Cook discovered the southern Atlantic Ocean island in 1775.

Birds nesting on the ground or in burrows, whose eggs and chicks were preyed on by rats, are already benefiting from world’s largest island rodent eradication scheme, according to the South Georgia Heritage Trust.

The song of the South Georgia pipit is back and flocks of South Georgia pintail are being reported, good news for two species found nowhere else on Earth, the trust said.

The announcement by the Scottish-based charity the island is rat-free comes after a habitat restoration project the team began planning in 2008, to return the island to its natural state.

Since 2011 teams have braved rain, snow and extreme winds to undertake three phases of dropping bait on vegetated areas where rodents are found, which are separated from each other by glaciers. Three helicopters were used for the work across 269,000 acres of the island, a range eight times bigger than any other eradication area tackled anywhere in the world, the trust said.

This winter, an expedition team dubbed “Team Rat” surveyed the island to see if the baiting project had been successful.

More than 4,600 detection devices including chewsticks coated with peanut butter, tracking tunnels and camera traps were deployed and

later checked for any signs of rat activity.

Three highly trained sniffer dogs, Wai, Will and Ahu, and their two handlers, walked hundreds of miles across the rugged terrain scouring

for evidence there were any rodents left alive.

Professor Mike Richardson, chairman of the project’s steering committee, said: “Over the last six months of work, not a single sign of a rodent has been found in the whole of the area we have baited.

“To the best of our knowledge this island is rodent-free for the first time in two-and-a-half centuries.”

Efforts are under way to ensure good biosecurity on the island, to prevent the reintroduction of rodents from ships that visit the island, where 33 species of birds nest.