How beavers are dam good for our rivers

BEAVERS recently reintroduced to Britain are already helping to reduce soil erosion and pollution, a study suggests.

Champions of beaver reintroduction claim their dams prevent flooding because they slow down the flow of rivers.

And scientists from Exeter University, who have been studying a family of the mammals in Devon since 2011, found their 13 dams have also trapped more than 100 tons of sediment.

Of this, 70 per cent was thought to be soil washing away from ‘intensively managed grassland’ fields upstream. The ponds are also storing tons of carbon in the sediment, along with nitrogen and phosphorus, which can cause problems for wildlife and water quality in streams and rivers.

The team has also found that the water leaving the trial site had lower levels of sediment and nitrogen.

Beavers, hunted to extinction in the 16th century, have been reintroduced to parts of Scotland and Devon.

The research, published in Earth Processes And Landforms, was led by Professor Richard Brazier, who said he was ‘heartened’ by the finding that beavers are boosting the environment.