The UK Overseas Territory of South Georgia is officially declared free of rodents for the first time since humans arrived on the, due to the world's largest rodent control programme.

Speed read:

• The Habitat Restoration Project is more than eight times larger than any other rodent eradication area tackled anywhere in the world
• Over 300 tonnes of bait were dropped by helicopters to eradicate invasive rodents
• Three rodent detection dogs covered a total of 2420km, searching for signs of rats and mice as part of a monitoring survey
• SGHT raised £10 million to finance the Habitat Restoration Project to eradicate invasive rodents
• Biosecurity measured in place to prevent this happening again.

The world’s largest rat eradication programme appears to have rid South Georgia of its pest problem.

With the song of the South Georgia pipit playing in the background, Professor Mike Richardson, Chairman of the SGHT Habitat Restoration Project Steering Committee, announced today that South Georgia is free of rodents.

We've been on tenterhooks - would there be a remnant enclave somewhere? But I'm pleased to say over the last six months, not a single sign of a rodent has been found. To the best of our knowledge, this island is now rodent-free.

Professor Mike Richardson, Chairman of the SGHT Habitat Restoration Project Steering Committee

The huge project is a great success for the Scottish charity who have lead the £10 million conservation project for the last decade.

Helicopters were used to drop over 300 tonnes bait into remote locations across the island’s coastal areas between 2011 and 2015.

Invasive species on South Georgia

Thousands of tourists travel to see the 165km-long island’s impressive wildlife which includes seals, penguins, albatrosses, and over 30 different species of seabirds.

Non-native rats and mice were accidently carried onto the island by whaling and sealing vessels from the late 18th century onwards.

Because of the lack of trees on the island, many of South Georgia’s unique species of birds are ground-nesting and burrowing birds.

Since their accidental introduction, the invasive rats and mice have had a devastating effect on the sea birds which evolved in the absence of natural predators.

Many of the seabirds had retreated to tiny offshore islands.

The rodents have threatened the existence of two endemic species found nowhere else on Earth:  

The world’s largest pest control project

SGHT started planning its ambitious Habitat Restoration Project in 2008, with the aim of reversing two centuries of human-induced damage to the island’s wildlife.

The aim was for millions of birds to reclaim their ancestral home. 

The Trust launched the pilot phase of baiting in 2011, followed by a second phase in 2013/14 and a third phase in 2015/16.

• Phase 1 – 50 tonnes of bait dropped by two helicopters in 2011
• Phase 2 – 157 tonnes of bait dropped taking over 600 hours of helicopter time in 2013
• Phase 3 – 95 tonnes of bait dropped by three helicopters
• Phase 4 – 16 members of ‘Team Rat’ complete a comprehensive monitoring survey to look for rats in 2017.

This first phase of baiting alone made this project the most extensive island rodent eradication operation ever undertaken in the world. 

The monitoring survey used 4,600 passive monitoring chewsticks and tracking tunnels, plus three rodent-detection dogs, to search the island for any sign of rats.

Dickie Hall, the director of the restoration project, told the press that every site they monitored saw evidence of South Georgia pipit and pintail’s returning.

Thanks to the outstanding work of the passionate and committed members of ‘Team Rat’ and the Board of Trustees, the birds of South Georgia are free from the threat of rodents.

Professor Mike Richardson, Chairman of the SGHT Habitat Restoration Project Steering Committee

The Trust, along with its US-based counterpart the Friends of South Georgia Island (FOSGI), raised £10million to finance the entire Habitat Restoration Project, securing financial and in-kind support from numerous individuals, foundations, businesses, and government, including £885K from the UK Government through DEFRA and the Darwin Initiative.

At the press conference, BPCA member, Bell Laboratories was thanked for their support providing the rodenticides used in the project.  

The future

Because of the scale of the project, if the island were to be re-infested with invasive rodents, it’s unlikely that the pest control work could be carried out again.

Tough biosecurity protocols are now in place to stop rats being reintroduced.

Tourist ships are not allowed to dock in the port, and government vessels must have their cargo baited and fumigated.

Rat detection dogs are also being trialled on the ships.

If one pregnant rat was to get to South Georgia, the invasive pest could once again devastate the island’s delicate ecosystem.

The last ten years has seen a step-change in how the UK responds to invasive non-native species and the rodent eradication work completed by the South Georgia Heritage Trust is undoubtedly among the most remarkable of recent island conservation efforts.  This successful project gives confidence and offers hope for invasive alien species management around the globe.

Lord Gardiner, Parliamentary Under-Secretary, DEFRA

Now the rodent eradication project is complete, South Georgia Heritage Trust can turn its attention to working with the Government of South Georgia & the South Sandwich Islands on the conservation and reinterpretation of the island’s historic cultural heritage.

Scott Johnstone
Content and Communications Officer
8 May 2017  |  BPCA Online

Source: Online