For the first time in centuries, there are beavers in London — on a stream in Enfield. Sadly, the female has been widowed, but the search is on for a new mate for her, and before long there will be kits too, tucked away in the beavers’ warm lodge.
Beavers were eradicated by people from Britain and from much of Europe, brought to the brink of extinction on account of the oil secreted from sacs beneath their tails, and their warm, waterproof fur. In recent years, however, a growing understanding of the vital, keystone role they play has seen beavers systematically reintroduced.
There is a particularly magical West Country woodland that I know, through which a sunlit stream meanders, braided by a series of neatly dammed pools that thrum with life. Dragonflies and mayflies, swallows, kingfishers, ducks, amphibians and small fish teem here in numbers rarely seen in Britain. The birdsong all around is cacophonous. The water’s edge is lined with the fresh growth of willow, hazel and alder, artfully coppiced as if by a skilful woodsman. This place happens to be home to a family of beavers.
Beavers are territorial, living in small family groups comprising a single pair and their young, who tend to hang around until their second or third year. Beavers use water as a means of escape, so while their food – the bark, twigs and shoots of trees, shrubs and other plants – is to be found on land, beavers never travel far from water. Life is straightforward for beavers with prized territories along broad stretches of water. But when these choice areas are all taken, young beavers looking to establish a territory of their own must make their way up into the streams and tributaries. It is here that they really make an impact. For without permanent deep water, beavers set about creating it themselves, using sticks, stones and mud to construct small dams, behind each of which they dig out a large pool that fills with water. Before long the stream resembles the flooded steps of an immaculately terraced rice paddy. These beaver-made ribbon wetlands abound with life.
Ordinarily winter rainfall brings a deluge of water rushing downstream into our towns and living rooms. As the summer comes around, flooding gives way to dry, lifeless watercourses and seemingly inevitable hosepipe bans. The ecosystem engineering of beavers in the landscape dramatically slows the flow, reducing both flooding and drought, while giving nature time to purify the water of sediment and pollution.
In areas where beavers do present a problem, such as in artificial, low-lying arable areas reclaimed from former wetlands, they must be managed, preferably non–lethally. But opposition to the return of beavers mostly arises from misunderstanding. There are worries that migratory fish such as salmon and trout might be unable to make it past beaver dams, which ignores the fact that these fish co-evolved over millions of years with beavers. And some people object to the ‘mess’ created by beavers along the water’s edge. Considering that the majority of our land is stripped, cultivated, tidied and managed by humans, surely we can we allow nature a bit of free rein along our watercourses.
Beavers may be the most powerful tool we have for breathing life back into our landscapes. Their return to Britain is truly a marvel.
