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Wait. There are beavers in London?
Good dam builders. 🦫
Earlier in October, Mayor of London Sadiq Khan had what looked like a lovely day out helping to release beavers into the wilds of West London (Ealing, to be precise) making them the first beavers in the area for over 400 years.
What you may not realise is these furry friends are not the first beavers to be released in London. That credit goes to the family of dam builders released in Enfield, East London, in 2022.
Let’s gloss over the fact that two of the beavers in Enfield died within a year, and focus instead on the new arrival of a baby beaver in the summer of 2023.
But why are beavers being released in London and what is so special about them?
Beavers used to be widespread across the UK, an iconic native mammal that was unfortunately both very furry and very tasty. Our cousins back in the Elizabethan era made short work of them, hunting and trapping them for their fur and meat, and they quickly vanished from the British landscape.
Fast forward to today, and wildlife and conservation organisations are championing the beaver and clamouring for their return in the face of declining biodiversity and intensifying climate hazards.
Because it turns out that beavers are incredible ecosystem engineers.
When left to their own devices, beavers will get busy. Their front teeth never stop growing, so they never stop gnawing - specifically on tree bark. They use the fallen trees to build dams across rivers and streams, slowing the flow of water.
“But rivers are meant to flow. Isn’t stopping them a bad thing?” I hear you asking.
Beyond simply rearranging the landscape, beaver activity actually makes it healthier. Firstly, the slowing of water creates a deeper pond and a wetland habitat. This attracts other species such as dragonflies, fish, birds, and aquatic mammals like water voles and otters, increasing biodiversity. It filters the water, reducing pollution further downstream. The wetlands acts as a carbon sink, absorbing greenhouse gases from the atmosphere and helping to mitigate the effects of climate change, and it absorbs excess water, dramatically reducing flash flooding.
This reduction in flooding is one of many reasons why the beaver is being re-adopted into urban environments like London around the country.
It’s been raining a lot here in the last few days. So much so that four people have died because of it. Due to the way that humans have drastically changed the landscape over the last few decades, flash flooding is commonplace. When towns and cities are nothing but tarmac and concrete, water has nowhere to go. When an unusual amount of rain blasts an urban environment, the drainage systems are quickly overcome, and flooding destroys lives and livelihoods.
Conversely, beaver-powered landscapes also retain water in times of drought. As overall groundwater levels drop, wetlands hold water and become a refuge for wildlife - and soil - in the local area.
In areas prone to wildfires, beavers are indispensible. This interview with California-based ecohydrologist Emily Fairfax is worth reading just for this wonderful 45-second video explanation of how beavers prevent the spread of wildfires.
But beavers are more than just firebreakers. I love this story in Scientific American about the discovery of a complex of beaver dams after a catastrophic wildfire in Oregon that acted not only as a wildlife sanctuary, but as a filter.
This was more than a refuge from fire, which hundreds of beaver dams are known to have afforded to other riparian areas. Whereas fish seemed to have disappeared upstream of the Dixon Creek dam site, the downstream water was crystal clear—and trout were thriving as though the fire had never happened. The dams and ponds appeared to have altered the hydrology of the landscape around them…The beavers had effectively built something like a water treatment plant that staved off fire-related contamination.
As we have spent the last hundred years degrading our landscapes, building over natural features, straightening rivers, and polluting water, it’s no wonder that the environmental movement has adopted the beaver as a symbol of rewilding - reverting the landscape back to its natural state.
The beaver reintroductions in London have been the result of some incredible work from London Wildlife Trust, Beaver Trust, Ealing Wildlife Group, Citizen Zoo, Ealing Council, Friends of Horsenden Hill and Groundwork London. The ambition is lofty: Dr Sean McCormack, chair of Ealing Wildlife Group and a key driver of this project, explains:
Paradise Fields is already a highly suitable habitat for beaver reintroduction, and we hope it will become a flagship London rewilding project. We’re enclosing most of the 10-hectare site and uniquely the project will allow visitors to enter an immersive experience in a rewilding beaver landscape, after a month of closure to allow the beavers to settle in.
I don’t know about you but I am very excited about the prospect of an immersive beaver experience.
But beaver reintroduction is not without its critics.
Beavers were reintroduced - possibly illegally - into Scotland a few years before any official reintroduction programs were explored in England. Numbers have been building gradually and they have established themselves nicely across Scotland.
Not everybody is happy about this. Farmers and landowners claim that beaver floods and tree destruction damage their property. In 2018, 87 beavers were culled under license in Scotland - nearly 20% of the population at the time. Few people dispute that land is flooded and trees are felled, causing localised economic losses. But even the Scottish government accepts the overall benefits of increased biodiversity, flood and climate mitigation and wildlife tourism. As a result they made the beaver a protected species in 2019.
I can envision a world where humans once again live happily alongside beavers. A beaver-powered landscape is a flood and drought-resistant landscape of fertile soil, biodiversity-rich wetlands, and happier people.
It won’t be an easy road. A family of beavers in London is an exciting start, but no more than two weeks after they were released the UK government has said that “reintroducing species is not a priority.” Instead (they say) they will focus on restoring biodiversity through habitat restoration and reducing pollution which are both admirable efforts, but it would be a sorely missed opportunity to ignore the rocket-propelled environmental booster that is the humble beaver.
There are plenty of other exciting rewilding projects going on, too. Blean Woods just outside Canterbury in Kent is now home to bison, another set of incredible ecosystem engineers. If the government doesn’t want to support them then it’s up to us to make sure the rewilding movement doesn’t lose steam.
Rewilding is environmental restoration on steroids, and we can help by supporting any of the wonderful non-profits mentioned in this article.
In the meantime, see you at the immersive beaver experience - London’s hottest new tourist attraction.