Mink could be eradicated after decades of killing native wildlife

They have cut a deadly swathe through British wildlife since escaping fur farms last century. But the tide is finally turning against the voracious American mink thanks to a remarkable team of volunteers and the latest technology.
Smart traps are now in place across a quarter of England and genetic analysis shows that the invasive species is not recolonising areas from which they have been cleared. Such is the success that some scientists believe that mink could be eradicated from the British landscape — a prospect once thought impossible.
Thousands of American mink escaped into the wild from British fur farms during the 1960s, and have since wreaked havoc on native species. The number of water voles, immortalised by the boat-loving Ratty in Kenneth Grahame’s The Wind in the Willows, has plunged by 90 per cent over the past 40 years.
But in the past three years conservationists and volunteers from the Waterlife Recovery Trust have removed mink completely from East Anglia. No mink have been caught in their 500 traps across the region for an entire year. After being captured the mink are killed and liquid from their glands is used to make scented lures to attract further mink to the traps.
With further funding and the help of wildlife charities and water boards, they have expanded their operations to cover 26 per cent of England in smart traps, from the Thames to Lincolnshire and the Midlands.
These floating cage traps are laced with mink scent and send a text message and email whenever an animal is caught, meaning they do not need to be checked every day. This reduced the number of trap visits by 98 per cent and enabled the hundreds of volunteers to cover vast areas.
Bill Amos, professor of evolutionary genetics at the University of Cambridge, told The Times: “It’s a huge area and we have actually started reusing traps from East Anglia. That is really extraordinary, given all the concerns before the project with people saying this won’t work because mink will recolonise an area.”
Amos has led the genetics analysis of the more than 1,600 mink caught in traps, which he said showed they did not tend to travel far.
He said: “We put a lot of genetic markers across every mink we trap and can work out pretty much where it was born. What you find is that almost all mink (90 to 95 per cent) were caught within 15 to 20km of where they were born and most were under 5km. They tend to stay pretty much at home, with males moving a tiny bit more than females.
“This wasn’t known before we started this project. We now know that actually they are not going to recolonise [cleared areas] that fast. That means we can keep track of them, certainly in England.”
Amos said that farmers were in tears as water voles returned to their land for the first time in decades. Once mink have been vanquished, water voles often seem to materialise out of thin air, even in places where none have been recorded for years or decades.
They have now become so common in some areas of East Anglia that volunteers are having trouble keeping them out of the traps.The mink-trapping operations have been done on a shoestring budget, with the East Anglia eradication costing only £500,000, with one paid project officer organising a team of hundreds of volunteer trappers.
Tony Martin, emeritus professor of animal conservation at the University of Dundee, has led the effort under the banner of Waterlife Recovery, a partnership between dedicated conservationists, wildlife charities and water management companies.
Natural England has spent a further £500,000 on the new trapping scheme ranging from the Thames to Lincoln. Trapping in Essex is funded through a grant from the Highways Agency to the Essex Wildlife Trust. Others helping to fund the project include Internal Drainage Boards, the Countryside Regeneration Trust, Hertfordshire Wildlife Trust and Thames 21, the environmental charity, all of which are arranging trapping in their parts of the project area, with more than 850 smart traps active.
But to clear the entire country of mink, which is now a realistic goal, they need more money.
“We do now need major funding because £500,000 doesn’t go far if you are trying to employ a project officer and genetics and go countrywide,” Amos said.“Tony [Martin] has estimated that it may cost £20 to £30 million. If you just plough money into water vole releases when you haven’t got rid of mink first then you are just going to end up with a lot of fat mink.“Several of us have put in quite a lot of our own money. I have put in £30,000 out of my own pocket to pump-prime it. But it’s such a worthwhile project and we are starting to get more and more funders involved. I think it’s only a matter of time before someone steps forwards and bankrolls the thing properly.
“I had to have my arm twisted almost off to join the project because I don’t need extra work at the moment but when I saw what was possible I had to join.”