Four years ago, a family of wild beavers were spotted on the river Otter in East Devon. This was the first report of the animal breeding successfully in the wild in England since the species had been hunted to extinction more than 400 years ago. No one knows how the animals came to be on the river but their prospering population is now the subject of a scientific trial providing a unique opportunity to monitor the re-introduction of a native species, or “rewilding” as it is sometimes called.
I wanted to find out more, so one evening in mid-September, I met Kate Ponting, Countryside Learning Officer for Clinton Devon Estates, at the village green in Otterton. Kate has been closely involved with the beaver re-introduction trial, taking place as it does on land largely owned by her employer. We headed to the river, crossed the old stone bridge and walked upstream along the muddy riverside path. Banks of Himalayan balsam and nettles dominated the river bank while, on the landward side, clover leys spread as far as the low embankment that once carried the railway. Prominent official signs warned that “Beavers live here” and Kate explained that there had been some local problems with dogs.
The river was full after recent heavy rain but the scene was tranquil in the low evening sunshine. We paused on the wooden bridge where Kate pointed out one beaver lodge, a semi-organised jumble of mud, sticks and branches protruding nearly a metre from the river bank and covering the entrance to a burrow where the beavers live. Further up the river we stopped to watch a second lodge on the far bank. Kate had warned me that the beavers had become less “reliable” as the autumn progressed and, although a wren flittered about the sticks making up the lodge and a grey wagtail passed through, we saw no beavers. Kate did, however, show me some signs of beaver activity including severed branches and one felled tree.
The beaver is Europe’s largest rodent and until the 16th century was found widely on UK rivers. They are impressively large animals covered in brown fur, measuring up to 100cm (head and body) and with scaly black tails. Beavers are strict herbivores with strong teeth allowing feeding on many species of river and bank plant as well as woody vegetation from trees. They are strong swimmers adapted for life underwater, and skilful aquatic engineers able to regulate water levels by building dams. When they build dams by felling trees they remodel the wetland landscape creating habitat for many other plants and animals and, for this reason, they are referred to as “keystone” species.
In the past, they were hunted to extinction for their fur, meat and castoreum, a secretion from their scent gland used for medicinal purposes. Early in the 21st century, however, free-living populations of beavers were re-established in Scotland and there were anecdotal sightings of wild beavers on the river Otter in East Devon. These reports were confirmed early in 2014 when two adults and one juvenile beaver (kit) were filmed near Ottery St Mary. This was the first confirmed report of wild beavers breeding in England for 400 years.
At first, DEFRA were concerned that the animals might harbour disease and wanted to remove them but their plan was opposed by wildlife experts and local people. So, towards the end of 2014, Devon Wildlife Trust applied to Natural England for a licence allowing the beavers to remain on the river as part of a five-year trial to monitor their effects. The licence was granted on the condition that the beavers were shown to be the native UK species and disease free and in March 2015, nine beavers living in two family groups were returned to the river Otter. The licence included a management plan for monitoring the health of the beaver population and its effects on the local landscape and ecology; also for making good any damage. The River Otter Beaver Trial is led by Devon Wildlife Trust working in partnership with the University of Exeter, the Derek Gow Consultancy and Clinton Devon Estates.
Since the trial began, beavers have been seen along almost the entire length of the river Otter. Breeding has been successful each year but there were concerns that the population might be becoming inbred so in 2016, two additional beavers, unrelated to the existing animals, were released on to the river. By 2017 the population had grown to more than 20 and watching the adult beavers and their kits on a summer’s evening became a popular pastime attracting many visitors to the area. So far, the presence of these large aquatic animals has caused few difficulties. Feeding signs have been detected all along the river in terms of severed shoots and felled trees but this was mainly confined to small diameter willow shoots. Earlier this year, fields near Otterton were flooded when beavers dammed one of the streams feeding the Otter but mitigation measures were put in place.
These are, however, early days and, as the number of beavers continues to rise, their presence in this managed East Devon landscape may cause tensions. There is good evidence from Bavaria, where the animals were re-introduced 50 years ago, that beavers can have a beneficial influence on rivers. They support wildlife by opening up the landscape, creating coppice and diversifying the wetland habitat. Their dams regulate river flows and remove sediment and pollutants. Sometimes, however, they can be a nuisance to those who live and work by rivers, causing flooding, blocking ditches, undermining river banks and felling important trees. There are now as many as 20,000 beavers on Bavaria’s rivers and their beneficial effects are clearly recognised alongside the need to manage the animals when their activity has a negative impact. Hopefully, a similar resolution can be reached for the East Devon beavers as their population grows. Whatever the outcome, the River Otter Beaver Trial will be closely watched by those interested in “rewilding” the landscape.
I should like to thank Kate Ponting of Clinton Devon Estates for giving up her time to show me the beaver lodges and Steve Hussey and Mark Elliott Of Devon Wildlife Trust for providing information and photographs.