Tthe dramatic sea cliffs, cliffs and stacks of Rathlin Island, County Antrim, rise more than 200 meters above the Atlantic Ocean and host one of Britain’s largest seabird colonies, including hundreds of endangered puffins, attracting up to 20,000 birders and tourists per the year.
On a spectacularly sunny day in September, the cliff faces are devoid of birds and the puffins have already made their annual migration to spend the winter months at sea. Instead, Rathlin’s cliffs are dotted with figures with ropes in harnesses and bulging rucksacks, controlled from above by a Scottish mountaineer via a walkie-talkie.
They are part of a crack team of 40 scientists, researchers, conservationists and volunteers who will this week put the first poisoned food into the bait stations designed to kill the island’s rats. It is the final phase of a £4.5 million project to eradicate the key predators believed to be affecting the island’s puffin colony. Ferrets were tackled in the first phase and it has been a year since the last confirmed sighting. According to an EU study, the number of puffins decreased by 74% between 1991 and 2021.
“It’s a monster task,” says Stuart Johnston, director of operations at Climbwired International Ltd, which trains scientists and researchers to access remote areas by rope. “Some of the highest cliffs in Britain are on this island. We can’t abseil down these cliff tops as they are basalt and laterite, and very crumbly. We have to go down, that’s where mountaineering comes in.”
Johnston and his crew have been preparing the ground for this event over the past year as part of the Life Raft project, a partnership between the EU and the National Lottery Heritage Fund, which includes the RSPB Northern Ireland and the local community association. He points to a horizontal stainless steel safety wire that runs across the middle of the 150m Knockans cliffs, onto which climbers are clipped to prevent them from falling into the Atlantic Ocean when they set the traps. The traps, or “bait stations” designed for rats, are plastic tubes fitted with wires to keep out crows, rabbits and other non-target species.
For the next seven months, come rain, snow or shine, the climbers will scale every cliff, cliff and stack and fill the traps with poison, while others will cover the fields, forests, gardens and other terrain. “The ledges are full of bird droppings and are just stirring,” says Johnston. “The stacks are full of rats.”
Rats probably arrived on boats centuries ago, and ferrets were released deliberately to control rabbits. They both feed on seabirds and their young, and until last year, when just under 100 ferrets were caught and killed in the project’s first phase, they were everywhere.
Eradication of rats and other invasive animals from islands is one of the most effective tools for protecting wildlife and has an 88% success rate, leading to dramatic increases in biodiversity, according to a 2022 study that analyzed data stored on the Island Invasives database Extinction of species.
By early October, 6,700 traps, one every 50 square meters – the size of a rat’s territory – had been laid in a grid pattern across the 3,400-hectare (1,400-acre) island. Now they will be filled with poison.
Born and raised in Rathlin, population 150, RSPB Warden Liam McFaul shows us around the rocks and stacks at the West Light Seabird Center and its ‘upside down’ lighthouse.
Below the viewing platform, two seals lie on the cobbled beach beneath the guano-splattered rocks. “In the summer, you can’t see the rock for loons, they all crowd into one area,” he says. About 200,000 auks (a family of birds that includes loons, puffins and auks) breed here, he says, and 12,000 breeding herons.
“Plovers come from the end of April to July. They find the same partner every year. They are notoriously difficult to count because they breed in burrows in the ground, which also makes them vulnerable.”
Years ago, they used to nest on the grassy “apron” at the top of the cliffs, but now stick to lower, more inaccessible areas, a behavioral change McFaul believes is due to rats and ferrets reaching the aprons. Once he saw a ferret at a puffin burrow near the beach and quickly organized a boat and a trap to catch it. When it arrived, 27 dead puffins were lying on the rocks.
On Rathlin, only one in three puffins survive, compared to two in three on rat-free islands, according to the RSPB. Ground-nesting birds, such as puffins and Manx shearwaters, are most at risk.
“We’ve had a serious decline in the Manx herd over the last 15 years,” says McFaul. “They may be on the verge of extinction from the island. We only have one or two left on the remote rocks to the north.”
Liam’s brother Jim McFaul, 75, a farmer on Rathlin, says the sky over the island has gradually quieted since the 1990s and early 2000s due to several threats, including changes in farming practices. “I used to love hearing snipe at dusk and night,” he says. “It’s like the sound of a drum. You hardly hear it now. The Marsh was different – ​​you couldn’t sleep for them, they called and answered each other all night.”
He hopes the eradication program will help birds as well as farmers. “Because of the ferrets, nobody could keep poultry. They’re like foxes. I caught dozens of them, some as big as polecats.”
The project will continue until 2026, when it is hoped that all ferrets and rats will be gone. After that, biosecurity measures will continue, including training ferry operators on how to minimize risks to rodents on board, such as removing food, inspecting animal feed and carefully monitoring vessels.
Woody, a two-year-old Labrador retriever trained to detect ferret droppings, was brought to the island this year to help identify any rogue animals and monitor the project’s success.
Michael Cecil, chairman of the Rathlin Development and Community Association and ferry skipper, says that while a few concerns have been expressed over the ethics of killing ferrets, as well as access to property needed for the project, the community was convinced of the benefits. Much of its economy is based on thousands of summer visitors, attracted by the seabirds.
“Illers caused all sorts of problems and people used any means necessary – they were run over, drowned, clubbed or shot with rifles, not the most humane way to kill them,” he says. “It’s coming to an end now.
“We can’t do anything about the wider worldwide problem facing seabirds, but we hope Rathlin will do its bit.”