Industrious beavers have already built what is believed to be their first dam on Exmoor, UK, in more than 400 years, after they were introduced as part of a river restoration project earlier this year.

The dam, which was discovered last month at the Holnicote Estate, in the English county Somerset, has created an instant wetland, according to the UK conservation body The National Trust.

Footage captured on wildlife cameras shows the animals gnawing nearby trees and collecting vegetation to create a dam across small channels of water.

Beavers were brought back to Exmoor nine months ago to slow the flow of water and improve river quality and biodiversity.

"It might look modest, but this beaver dam is incredibly special – it's the first to appear on Exmoor for almost half a millennium and marks a step change in how we manage the landscape," said Ben Eardley, project manager at the National Trust. 

"What's amazing is that it's only been here a few weeks but has created an instant wetland. We've already spotted kingfishers at the site, and over time, as the beavers extend their network of dams and pools, we should see increased opportunities for other wildlife, including amphibians, insects, bats and birds."

Beavers are often referred to as "ecosystem engineers." Given the right conditions, they can build dams to create deep pools of water, which offer shelter from predators and places to access and store food.

This evolutionary response enables them to move around their habitat more easily and, crucially, turns the surrounding land into a mosaic of nature-rich habitats.

Beaver dams, ponds and channels can also help prevent flooding by slowing, storing and filtering water as it flows downstream. The animals create space for water and wildlife, leading to a more resilient river catchment.

"The recent rain we've had is a reminder of the significant role beavers can play in engineering the landscape," said Eardley.

"As we face into the effects of climate change and more frequent extreme weather events, natural interventions like this need to be part of the solution."

Beavers disappeared from the country in the 16th century due to hunting for their meat, fur and scent glands. Since the early 2000s, they have been reintroduced at a handful of sites in the UK.