Today conservation charity the Waterlife Recovery Trust (WRT) has announced the results of a ground-breaking trial that has shown the feasibility of eradicating non-native American mink across almost 6,000 km² of East Anglia.

Until now American mink have never been successfully eradicated from any part of Britain. The sheer scale of this trial shows that a mink-free Britain is now a realistic dream, and that American mink can potentially be removed from Europe too, putting this unique trial on the world conservation stage.

The ambition now is to expand this method of pest eradication across Britain, giving hope to conservationists everywhere that this invasive predator can be removed and allow the recovery of many of the UK’s vulnerable animal species, especially the water vole which has seen a 96% decline since 1950, largely due to mink.

The trial was developed by a group of conservation charities, water management bodies and other organisations in 2019 under the banner of The Waterlife Recovery East partnership. From this partnership grew the Waterlife Recovery Trust, a charity aiming to expand the work and its resulting conservation benefits across the country. WRT is chaired by Professor Tony Martin, a specialist in the field of eradicating invasive non-native predators for the benefit of native wildlife.

The trial built on long term control projects in Norfolk and Suffolk, and a major contributor to the success has been the support of many hundreds of conservation volunteers working alongside and guided by a professional team to deliver an outstanding result across a huge geographical area. Although there have been a few large-scale mink control projects in East Anglia and Scotland over the past few decades, none have achieved eradication. Protection of vulnerable local wildlife lasts only as long as the funding. When that runs out, mink soon return. Smaller control projects also invariably fail to prevent the continued loss of water voles and other vulnerable native species.

Coupled with such volunteer support, innovative new methods have played a key role in the success of the trial. These include 'smart' cage traps (which increase animal welfare and reduce volunteer time compared to traditional traps), and the use of pungent scent lures, harvested from captured mink, to attract other mink.  

The trial area had to be protected from immigrating mink, and large enough to be a true test of eradication feasibility. The central and eastern parts of the adjoining counties of Norfolk and Suffolk provided a 'Core Area' of 5,852 sq. km (almost 5% of England) for the trial, hosting 441 smart traps and defended by the North Sea on two sides. The establishment of traps across a 60 km wide 'Buffer Zone', which wraps around the Core Area, prevented mink entering from the west and south.

In October 2023 the trial was declared successful, as the team found no evidence of mink reproduction within the Core Area during the 2023 breeding season, and consequently eradication was assured. Now, the WRT plans to roll out this methodology across Britain.

Speaking about the trial, Professor Tony Martin, Chair of the Waterlife Recovery Trust said: “Until now, the complete removal of American mink from Britain has been an impossible dream, but the success of this trial is of international importance and offers hope that a century of catastrophic damage to native wildlife can be brought to an end. The challenge now is to roll this work out across the country, bringing together the resources and energy of everyone with an interest in healthy waterways and a thriving waterside ecology to fix this problem once and for all."

"With mink in our countryside, the sad reality is that something is going to die - either a relatively small number of introduced predators or millions of native creatures every year, in perpetuity. The choice is ours, but to sit on our hands and do nothing condemns the millions. We now have a golden opportunity to fix a problem we've inherited and not simply pass on an even more impoverished natural world to the next generation. Nature has a remarkable ability to bounce back, given half a chance. Let's give it that chance."

Building on the trial’s success, the WRT has secured funding of £500,000 from Natural England to expand its work across a vast area that wraps around the existing Buffer Zone, from the Thames to mid-Lincolnshire. A second grant from Natural England is being used to maintain the trapping network in the Core Area, as although the trial has been declared successful and no breeding females have been found, a small number of isolated mink may remain or may sneak in from elsewhere. This second grant will ensure that any mink in the area will be removed and the species does not return. Crucially, it will also support the continued recovery of water voles and other native species.

Darren Tansley, Wilder Rivers & Protected Species Manager, Essex Wildlife Trust, said:

“Essex Wildlife Trust has been in involved with the Water Vole Recovery project for nearly 20 years and is a partner of the Waterlife Recovery Trust, so the success of the initial pilot in removing mink from nearly 6000km of East Anglia is cause for celebration. The Eastern Region is currently the only one in the UK with a naturally recovering water vole population and funding has been secured to roll this out across the remaining rivers in Essex that are not yet in the scheme. This is a major conservation success story for the 21st century.”

Dr Julie Hanna, Principal Adviser: Species Conservation Strategies Pilots, Natural England, said: “Natural England is pleased to be supporting Waterlife Recovery Trust as we develop a pilot Species Conservation Strategy for water vole with partner organisations. We hope the trial will help recover water vole populations, and benefit other species which have been affected by American Mink.”

The success of the trial wouldn’t have been possible without the collaboration between the Waterlife Recovery Trust and Anglian Water, British Association for Shooting and Conservation, Broads Authority, Countryside Regeneration Trust, Environment Agency, Essex Wildlife Trust, Greater Lincolnshire Nature Partnership, Herts and Middlesex Wildlife Trust, Natural England, Norfolk County Council, Norfolk Rivers Trust, River Waveney Trust, RSPB, Suffolk Wildlife Trust, Water Level Management Alliance and the University of Cambridge.

Anyone in Britain can help by either volunteering to monitor local cage traps or by reporting mink sightings to the Waterlife Recovery Trust. To find out more, visit www.waterliferecoverytrust.org.uk