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The epic battle to make South Georgia a rat-free haven for wildlife

One of the best wildlife experiences I had when I visited South Georgia last year was also one of the most unexpected. I was standing in the tussac grass at Salisbury Plain, almost deafened by the metallic trumpeting of its enormous king penguin colony, when one of the guides told me to look up. As I turned my head, a tiny brown bird flew ten feet above me and started to sing. The sound of the penguins faded away to be replaced by the joyful song of a lark. 

I was listening to a South Georgia pipit, the world’s most southerly songbird. And no wonder it sounded so happy. Even ten years ago it would have been almost impossible to hear it sing. That I could that day is proof of one of the most extraordinary conservation projects of recent times, run by the South Georgia Heritage Trust. 

A South Georgia pipit (Anthus antarcticus) photographed whilst I  was working on the South Georgia Heritage Trust's Rat Eradication Project in South Georgia, Antarctica on February 01 2018. The South Georgia pipit is one of the key endemic species being protected by the eradication of rats on South Georgia. Photo: Oliver Prince.
A South Georgia pipit (Image: South Georgia Heritage Trust/Oli Prince)

Since the first sailors called here in the late 18th century, the relationship between humans and South Georgia’s wildlife has often been an unhappy one. Sealers plundered its shores and whalers did their best to empty its seas. And they left behind some very unwelcome guests: rats and mice. 

With no natural predators, these rodents wreaked havoc on South Georgia’s birds. They didn’t bother bigger species like penguins and albatrosses but instead grew fat raiding the nest burrows of the smaller petrels and prions, along with species like the pipit and the South Georgia pintail duck. The birds only survived in small numbers on the tiny rat-free islands off the coast. 

Brown rat on South Georgia_credit Paula O Sullivan
Brown rats were introduced by sealers and whalers (Image: South Georgia Heritage Trust/Paula O’Sullivan)

Something had to be done. In 2011, the South Georgia Heritage Trust began a habitat restoration project to eradicate the rodents from the entire island. On paper, the plan looked simple: use helicopters to drop a specially formulated bait and monitor the results. The rodents were restricted to particular areas of this 100-mile-long island, hemmed in by glaciers spilling down from the mountains. By baiting one area and moving on to the next, South Georgia could be slowly but methodically made rodent free. Given the size of the island, the project would take three seasons to complete.

In truth, South Georgia’s wild remoteness – the very qualities that draw visitors there – presented plenty of challenges of its own. ‘There can be few places in the world more logistically challenging to undertake such a huge and complex field project,’ the SGHT CEO Alison Neil told me. There is no airport on the island, and everything had to be brought in by ship, from the three helicopters with their fuel, spare parts and hundreds of tons of bait, to all the logistical material to support the teams in the field. 

There was also South Georgia’s notorious climate to deal with. ‘We had to be prepared to be patient as we knew the winds and weather would likely prevent us from working for days, and maybe weeks, on end.’

The project was unrolled over three seasons, with the first phase dedicated to eradicating the rats in the 50 square miles around Grytviken. At the time, this alone was the largest eradication programme in the world. After a full season of baiting, the area was carefully monitored to confirm both the absence of rats but also that the project had had no deleterious effects on the native wildlife.

Despite this initial success, time was of the essence. Climate change had set the clock ticking on the project. ‘We had to push on to get the Habitat Restoration Project underway as quickly as possible due to glacial retreat,’ says Neil. Since the 1950s, 97% of South Georgia’s coastal glaciers have shown significant shrinkage: a fact that had serious implications for removing the rats according to Neil. ‘One, the Neumayer Glacier, was retreating at a rate of two metres a day through this period. If we had waited a few more years, it was possible some areas would become so large that they could not be cleared.’

Phase II. Helicopters over glaciers_Credit Tony Martin
Helicopters flying over glaciers in Phase 2 of the eradication project (Image: South Georgia Heritage Trust/Tony Martin

The project’s second phase concentrated on the northern end of the island, scaling up operations to cover an area four times the size of the first phase. This included landing sites popular with expedition cruises ships such as Fortuna Bay, Right Whale Bay and Salisbury Plain. This is also the part of the island with most of the abandoned whaling stations – locations that are dangerous to work in themselves and are off limits to regular visitors. 

While ruined buildings demanded that bait be spread by hand, one of the challenges for the helicopter pilots baiting from the air was to fly in repeatedly straight transects, akin to ploughing a field to make sure that not a square foot of potential rat territory was accidentally missed. Even more challenging were the steep slopes favoured by burrowing petrels where rats could take shelter, demanding that pilots flew their helicopters perilously close to the cliffs to set their bait. 

Rat Eradikation Project 2013
Handbaiting in the ruins of Husvik whaling station (Image: South Georgia Heritage Trust/Roland Gockel)

Only when the third phase was completed – and follow-up monitoring showed the areas were rat free – could the third phase begin in 2015, covering the southern third of South Georgia. In due course, the battle was won there. In 2018, after repeated monitoring including the use of specially trained rodent detection dogs, the announcement could finally be made: South Georgia was officially declared rodent free. With their habitats safe to nest in once again, the ducks and pipits quickly recolonised the mainland and have become common sights for the first time in living memory.

Miriam Ritchie with her rodent detection dogs Ahu and Willl photographed working on The South Georgia Heritage Trust's Rat Eradication Project at Macdonald Cove in South Georgia, Antarctica on March 08 2018. Photo: Oliver Prince
Rodent detection dogs were key members of the monitoring team (Image: South Georgia Heritage Trust/Oli Prince)

The total cost of the project was £10 million. Alison Neil is quick to acknowledge that the efforts went far beyond those working on the ground. ‘We also had incredible support from the cruise operators who visit South Georgia, the Government of South Georgia & the South Sandwich Islands, the British Antarctic Survey and the island conservation community worldwide.’ Tourists visiting the island also played their part, with thousands of them contributing donations. At one stage in the project, the eradication crew even baked rat-shaped cookies to sell on expedition cruise ships for fundraising.

With the island now rat free and its bird population in full recovery, constant vigilance is needed to protect this fragile ecosystem. SGHT helps support the biosecurity detector dogs that search all vessels coming to South Georgia to ensure rodents never reach the island again, as well as sending staff on board expedition cruise ships when they dock in Grytviken to talk about their continued conservation work and underscore the importance of maintaining strict biosecurity during their visit. 

Flock of South Georgia Pintails on a pond_credit Oli Prince
With no more rats, South Georgia pintail ducks are an increasingly common sight (Image: South Georgia Heritage Trust/Oli Prince)

For anyone travelling to South Georgia today, the fruits of this epic habitat restoration project are clear to see. Most people arrive excited to see the king penguins and fur seals. These headline-grabbing species are truly amazing of course, and their almost uncountable numbers are what makes this island the Serengeti of the Southern Ocean. But while you’re there, listen out for a small brown bird with a heavenly voice. Its song might be the most potent reminder you can get of what nature can be like when humans remove any obstacles to its recovery. 

All visitors to South Georgia are invited to partner with the South Georgia Heritage Trust or its US affiliate Friends of South Georgia Island to help support its research and conservation projects. 

If you want to hear the song of the South Georgia pipit for yourself, then Swoop Antarctica are the South Georgia experts: Get in touch today and let us help you plan your polar journey.

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Paul Clammer

Guidebook Editor

Paul came to Swoop after spending nearly 20 years researching and writing guidebooks for Lonely Planet. On his most recent trip for Swoop, he fell in love with the epic landscapes and uncountable wildlife of South Georgia.