But on a national level, although many have welcomed the Devon beavers’ reprieve, others are not so sure. Perhaps predictably, given its opposition to reintroduced species, the National Farmers’ Union is concerned about ‘damage to farmland’ and the risks of disease.It’s easy to understand such worries when you think of those Disney films in which beavers gnaw their way through trees to build enormous dams across rivers, creating vast lakes and transforming the landscape.The good news is the animals in Devon are European beavers, a different species from their North American cousins. They do build dams, but in shallow water, and on a much smaller scale. So although they will change the landscape, this will happen at a gradual pace. In fact, the beavers on the River Otter have yet to build any dams, despite having been at large for up to five years. And the evidence suggests that rather than causing flooding, beavers act as nature’s engineers, helping to prevent floods by slowing the flow of rivers.
This creates more complex habitats for other river wildlife, such as amphibians, dragonflies, kingfishers and the endangered water vole. As someone who lives in the Somerset Levels — a landscape recently devastated by floods — I welcome the return of these charismatic and beautiful animals to my local patch.But anglers are among those strongly opposed to reintroducing them. The Angling Trust, the body representing fishing interests in England, talks of ‘huge potential risks to rivers’, with the creation of barriers that prevent the upstream movement of salmon and eels, and the erosion of river banks.In fact, European beavers — whose global population fell to 1,200 at the turn of the 20th century — have been successfully reintroduced to more than 20 countries without problems. And studies have shown that rather than harming fish, beavers help them by providing sheltered spawning grounds and cleaner water.
Some of the confusion about their threat is down to the belief that they are ruthless carnivores that clear rivers of fish and eat ducklings.This is wrong. Perhaps the myth arose because of their huge size and weight (about the same as a medium-sized border collie) or those fearsome teeth, but beavers are vegetarian.Another problem for beavers is people lump them with a predator terrorising our river wildlife: the North American mink. This non-native species was imported to Britain since the Thirties to be housed in farms to produce luxury fur coats.Being resourceful animals, many have escaped. The problem got worse in 1998 when, in an act of monumental stupidity, animal rights activists ‘liberated’ thousands into the wild.Mink are effective killers, and their mass arrival spelt disaster for one of our best-loved native creatures — the water vole, immortalised by Ratty in Wind In The Willows. They simply didn’t have a chance: unlike otters, mink are small enough to get inside water vole burrows.