Tony Jackson's Country Casebook
PUBLISHED: 14:08 15 April 2015 | UPDATED: 14:08 15 April 2015
This month our columnist considers the impact of the reintroduction of a species last seen in this country hundreds of years ago
Beavers are back and by now many readers will know that a small colony of Eurasian beavers (not the slightly larger Canadian beaver) has become established on the River Otter, not far from Ottery St Mary.
It is believed that there may be up to ten animals in the colony, including several kits (young), though it is not known where they have come from. For the past four years the Devon Wildlife Trust has been running a captive beaver trial at a securely enclosed location in West Devon but there have been no escapes, so the presence of the free-living colony is something of a mystery.
However, the fact of the matter is that in Devon, and also in Scotland where another beaver trial has been taking place since 2007, beavers have now returned to the United Kingdom. There has, inevitably, been a degree of concern, even controversy, over the presence of these animals, with some opponents claiming that they may introduce disease, destroy foliage and trees and have no place in today’s environment.
However, proponents have won the day with the result that the animals will be caught to ensure they are healthy and then returned to the water where, over the next five years, they will be monitored by the Devon Wildlife Trust which has been granted a licence by Natural England to check their impact on the landscape, economy and local community. This will be known as the River Otter Beaver Trial.
It is almost certain that, whilst once relatively common throughout Britain, these animals, hunted for their fur, were wiped out by the 12th century and not, as the Devon Wildlife Trust seem to suppose, the 1700s. There is reference to their presence in Wales in the mid-10th century with a statement that King Howel Dda was “to have the worth of Beavers, Martens and Ermines in whatsoever spot they are killed, because from them the borders of the King’s garments are made”. Beavers may have existed a little longer in Scotland but by the end of the 12th century it is certain that they were extinct countrywide.
Two attempts have been made to naturalise the Canadian beaver in the UK. In 1868 the animals were released on the Little Ouse in Suffolk near Wrangford and although they bred and began to colonise areas, they were wiped out by trapping. Six years later another attempt was made with the release of four beavers on the Isle of Bute. Their numbers increased to 16 but by 1890 they had died out, were trapped or shot.
What is the lifestyle of a Eurasian beaver and, if established in its former home, is it likely to have any detrimental effect on the landscape and the environment? We have already seen the appalling damage inflicted by the introduced grey squirrel and the escaped mink, so can we afford to encourage the presence of this large rodent which can weigh up to 25kg?
My own view is positive. The animals are aquatic, entirely herbivorous and do not eat fish. In fact, beavers have a positive impact on fish populations by creating pools and refuges. On the other side of the coin, as the Devon Wildlife Trust points out, any dams they construct may have a negative impact on migratory fish such as sea trout and salmon and this is an aspect of their presence which will have to be monitored.
Beavers are confined to river courses and rarely move more than 30m from water in search of food and in the summer they tend to consume herbaceous vegetation, while woody shoots are their favoured winter fare. Trees are coppiced to obtain their leaves and bark, while branches are employed to build dams in shallow water, though no dams have as yet been built on the River Otter.
Personally, I believe that this is one re-introduction which can be welcomed. It is fascinating to see how our native fauna is changing…wild boar have returned, now beavers and there is even talk of lynx, while the more extreme amongst their protagonists would like to see wolves and bears roaming in Scotland. I think not, somehow!