Two families of Beavers wrre observed in the River Otter in East Devon a decade or so ago. No one knows how they arrived there, but when it bacame piublic knowledge, the government asked the local authority to destroy them, as they were regarded as pests with no legal protection.
Beavers were eradicated in the UK 400 years,ago, and a local conservation group asked for a stay of execution, to see what impact it would have on the environmet. The Government agreed to that request, and the results have been transformative.
The river flows have reduced to such an extent with their dams, flooding has been eliminated in the towns down river.
The new wetlands that have formed with the increase in the water table have produced a haven for flora and fauna, and the quality of the river water has increased by such a margin, the river is alive with plants, crustaceans and fish.
The impact they had in such a positive way has been so successful, the government allowed their release in other parts of the country, and an area in Scotland where they were set free is now reporting similar benefits of reduced flooding and increased bio diversity.
Beavers are now a protected species in the UK, and families have now been released in parts of Wales and also Delamere Forest.