‘Beaver-bombing’: unauthorised rodent releases on the rise in English rivers

“Beaver bombing”, covertly releasing beavers into the countryside, is increasing in England because successive governments have not fulfilled promises to permit some planned wild releases, conservationists are warning.

Beavers now live freely on river systems across swaths of southern England, and conservationists are calling on Labour to allow official releases of free-living beavers and produce a national strategy to maximise the biodiversity and flood alleviation benefits delivered by the industrious mammals.

Eva Bishop, of the Beaver Trust, said: “Beavers are a native species with lots to offer in terms of landscape resilience, boosting biodiversity and climate change adaptation and mitigation. It would be crazy not to look at wild release as a key tool for the government.”

According to Bishop, the failure of recent Conservative governments to approve or even reject wild releases, or clearly signal what is required in terms of funding, has led to unauthorised releases that could jeopardise the 69% public support for their wild release.

Numerous scientific studies in Britain have shown beavers help restore water quality, wetland biodiversity and can ameliorate drought and flooding.

Beaver numbers are increasing in Scotland and are legally protected in England since being formally recognised again as native mammals in 2022. Animals unofficially released on the River Otter in Devon in the early 2000s successfully bred and spread but recent administrations backtracked on Boris Johnson government’s promise to allow free-living beavers to be released in certain locations.

Despite no official releases, beavers have turned up on river systems across Devon and spread through Somerset to Wiltshire and Gloucestershire. An established population has been living freely and largely unnoticed in lowland Kent for years and now numbers 51 territories – more than 200 animals.

There are also more than 30 large fenced enclosures where beavers have been reintroduced into England under official schemes. Conservationists say these populations will soon outgrow the enclosures, leading to animal welfare concerns because territorial beavers will fight to the death.

Bishop said: “It’s in everyone’s interests – landowners and farmers as well as conservationists – to get a clear policy now. A potential consequence of inaction is a growing number of unlicensed releases into the wild which could alienate stakeholders and jeopardise the success of future wild releases.

“It’s really important releases are done responsibly, under licence and to a strategy – then we can maximise the benefits that beavers bring through their damming and habitat modification.”

Three proposals to introduce free-living beavers – in Cornwall, Dorset and on the Isle of Wight – are well advanced but the application process is so onerous that a pre-application assessment of the impacts of returning beavers to the Isle of Wight is 100,000-words long.

Debbie Tann, the chief executive of Hampshire and Isle of Wight Wildlife Trust, said: “We’ve got beavers living wild quite happily and quietly [across southern England] and yet to get a licence to release a native animal back into its natural habitat we’ve got to do this 100,000-word application to assess its impact on every single aspect of everything.”

The trust has been working since 2019 on an application to release free-living beavers on to the island. Tann said: “The science of how important they are, what they do to revitalise rivers, boost biodiversity and minimise flooding are very well evidenced. We’re hoping the new government will honour previous commitments and open the application process so we can just get on with it.”

She added: “This isn’t about beavers per se. It’s about the restoration of ecosystem function and resilience in terms of drought and flood management, biodiversity recovery and soil health. This will tick loads of different boxes, and there are tourism benefits too and getting the public excited about this idea of nature restoration.”

Steve Reed, the environment secretary, has suggested in a letter to conservationists that applications for free-living beavers will be considered in certain locations. Conservationists hope that approval could be a flagship nature restoration policy for the government’s first months.

Tann said: “This could be such a positive thing for your first 100 days in government. The stats are there, the evidence is there, we know how to manage beavers in the unlikely event they cause issues and there’s huge public support for them.”

Key to the scale of future wild releases is how long the government says each release project must be self-funded. Crucially, it is still unclear if there will be any central government cash to pay for future beaver management.

Occasionally if beaver dams cause flooding on valuable farmland, then secret pipes known as “beaver deceivers” may have to be installed to allow water through the dams or beavers may need to be relocated.

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There has been widespread concern from farmers and landowners that beavers could cause unwelcome floods if they are released on lowland rivers surrounding low-lying land but the wild beaver population in lowland Kent are not building dams because the waterways are deep enough for them to feel secure.

Derek Gow, of Keep It Wild Trust and an expert in captive breeding animals for wild release, said: “The beaver is nature’s healer of the earth but its wild release has been held back by [former environment secretary] Thérèse Coffey and the National Farmers’ Union. There’s no reason why we shouldn’t be doing this right now. I don’t know whether Labour are on this, they’ve not made any statements about what they’re going to do about nature restoration other than windy ones.”

A spokesperson for the Department for Environment, Food and Rural Affairs said: “This government supports species reintroductions where there are clear benefits for nature, people and the environment.”