As much as 95 per cent of South Georgian birdlife is estimated to have been killed since mice and rats first scurried off ships in the 18th century. Their ruthless predatory instincts made it impossible for many birds to successfully nest, leading to species such as the South Georgia pipit and the South Georgia pintail – both unique to the area – surviving only by breeding on small rat-free offshore islands.
However, the first pipit nest in over 200 years was recently observed in the west of the island – traditionally a highly rodent-infested area. Project Director Tony Martin (also Professor of Animal Conservation at the University of Dundee) is optimistic that the island can soon be officially declared rat-free. ‘I spent days traipsing across the island looking for rodent signs; we found none,’ he says. ‘South Georgia is now genuinely, I think, free of rats.’
South Georgia rat (Image: Paula O'Sullivan)
As reported by Geographical in 2012, The £7.5million programme saw 290 tonnes of rodenticide-infused bait pellets, manufactured to survive the extreme wet conditions of the islands, distributed by three helicopters across 1,050 sq km of South Georgian coastline.
They also had to race against the rapidly melting glaciers along the centre of the island, which previously acted as natural barriers against rodent migrations. The melting exposed more land for the rats to inhabit, requiring the bait to be spread over an increasingly wide area, to the point where it was becoming unfeasible. ‘This whole project would not be possible in five years time,’ admits Martin.
A follow-up survey will be conducted in late 2017, which the South Georgia Heritage Trust hopes can be followed by an official confirmation that the islands are indeed rat free. However, Martin stresses it will be far longer before the islands are recolonised by the native bird species. ‘We know it’s going to take many decades, I suggest it could take two or three centuries,’ he says, ‘but it will happen. I shall go to my grave completely confident that it will happen.’
This article was published in the August 2015 edition of Geographical Magazine
