European beavers

In parts of Europe these animals are now well established. 

01/04/2008

With reports last month of beavers from the Cotswold Water Park escaping from their enclosure and paddling down the Thames towards Oxford, and with Scottish Natural Heritage all set to resurrect their experimental release at Knapdale on the west coast, it is worth considering how we will cope if the European beaver was to become re-established in Britain again.

One good place for comparison is Bavaria where approximately 120 beavers were reintroduced between 1966 and 1977. Since then they have spread throughout much of the region with probably 10,000 animals occupying 2,500 beaver territories (they live in family groups) today.

What is clear in Bavaria is that beavers have a very significant affect on riparian habitats but their activities depend very much on topography and the nature of the river. In the headwater regions, where small torrent streams run through mixed forest and glades, beavers build a succession of small dams so the streams become a series of small ponds with occasional riffle sequences in between. The beaver cuts down mainly small deciduous trees often letting light into a stream that would otherwise be heavily shaded.

On the lower reaches beavers live along the main stem of the river Danube and its tributaries, as well as numerous oxbow lakes, backwaters, farmland drains and fishponds. Here they make few impoundments but readily dig tunnels into the bank to construct their lodges.

The main management concerns are: the integrity of flood-control dykes; the cutting down or ring-barking of riparian trees, often up to between 30-50cm in diameter; blocking drainage ditches; and damaging small areas of maize, oilseed rape, sugar beet and winter wheat. Bavaria employs two full-time beaver managers and 200 volunteer consultants who respond to damage complaints and, if needed, live trap the beavers and move them elsewhere. Bavarians believe that management and close liaison with farmers and foresters is essential for living with beavers.