Beavers maintain wetlands that would otherwise become ‘muddy puddles’ in drought

Forget the hosepipe bans – busy beavers are helping to fight the drought in the UK by building dams that maintain wetland areas.

The rodents enjoy deeper water, so when they notice their habitat is getting too dry they get to work damming, creating ponds and excavating waterways.

This helps areas become more resilient to climate change by cooling the surrounding lands and air, as well as through flood prevention.

Land managers have noticed that wetlands where beavers have been introduced are not drying out during the current spate of hot weather in the country.

This includes the Holnicote Estate, a National Trust site in Somerset where two pairs of the animal engineers were introduced in an enclosure in 2020.

Beavers were once native in Britain, but were hunted to extinction in the 16th century, both as vermin as well as for their meat, fur and pelts.

However they have since made a return to the wild in some parts of the country, including in Scotland and a small number on the River Otter in Devon.

At Holnicote, on the edge of Exmoor, two pairs were released into two woodland enclosures in 2020 to help manage the landscape and habitats.

Ben Eardley, the project manager for the site, told The Times that the nearby River Aller is very low as a result of Britain’s recent heatwaves.

Without their beavers, Grylls and Yogi and their son Rashford, he said areas of the estate ‘would just be just muddy puddles’, but are instead ‘brimful of water’. 

Mr Eardley added: ‘The multiple dam complexes created by Grylls and Yogi and Rashford over the last two years have helped slow the flow of water through the catchment, creating ponds and new channels to hold more water in the landscape.’

At a second site at the Minehead estate, another beaver couple has created channels of flowing waters that have brought in an influx of fish, amphibians and dragonflies.

Parts of the UK are experiencing the driest conditions since the drought of 1976, and this is especially felt in the South East where temperatures have exceeded 40°C.

While some counties like Kent and Sussex have implemented hosepipe bans to cope with the lack of rain, two Eurasian beavers are actively reversing the drought’s damage.

The animals were installed on the Knepp estate in Horsham in February, as part of a licenced trial with the rewilding project Knepp Wildland.

Since their arrival, they have transformed what was once a small stream into a network of ponds and channels with lush green plants.

It is currently illegal to release beavers into the wild, so the two rodents are confined to a two-hectare enclosure.

However, the pen has not managed to stop the standing water and moist soils from spilling out into the surrounding landscape. 

Penny Green, resident ecologist at Knepp Wildland, said: ‘We’ve seen really amazing results just in the five months they’ve been here.

‘The beavers have already made a little network of ponds from the damming that they’ve done, they’ve been chewing back some of the vegetation in the ponds and we’ve got little beaver lawns.

‘But the most interesting thing for us at the moment is that even though we’re in a huge drought year, and most of the little streams either side of the enclosure are running dry, here in the beaver pen it is the most amazing wetland oasis all around us.’

Beavers maintain wetlands by building dams that direct flowing water into their habitat, forming ponds that allow access to more  plants, leaves and bark for eating.

To build a dam, they first create a scaffolding by driving branches into the ground and piling up sticks and organic matter.

They then coat the structure with mud that they pat down with their strong, flat tails, and continue to extend it outwards to encourage more and more water to flood in.

As time passes, the branches of the dam take root and begin to grow, creating a living ecosystem that attracts other wildlife like birds, insects and bats.

Outside of the enclosure, the backed up water has created further wetlands where large mammals, such as deer, pigs and cows, can drink.

The dams support the environment through droughts because of the small holes the beavers leave in them.

These allow water to trickle through all year round, even during long periods of particularly low rainfall in the summer.

The ponds that form as a result of the beavers’ work also help lower the water temperature, as deeper water is often kept cooler.

When the water spills out into the surrounding environment, as a result of the leaky dams or groundwater seepage, it further cools the land.

The large surface area of the ponds also encourages evaporation, which additionally helps to cool the air itself.

The 60-pound engineers do not just help during particularly hot weather, but their dams also help to alleviate flooding during heavy rainfall.

They hold onto water and slow down its flow, giving the ground and vegetation time to absorb more of the rain.

While it is currently illegal to release beavers into the wild, the UK government have given them legal protection which will initiate from October 1.

This makes it a criminal offence to deliberately capture, kill or injure beavers, or damage their lodges or dams.

Consultations are still ongoing about whether they will be able to be released in the country in the future.