BACE

The five-year trial on the reintroduction of beavers to Knapdale Forest, Argyll in Scotland finished in May 2014 and Scottish ministers will decide in 2015 whether the beavers at Knapdale, and those on the River Tay (founded originally by escapees from captivity, see SNH, Scottish Wild Beaver Group), can remain or will have to be removed. The reintroduction team have just produced their final report; this follows the recent publication of six independent studies by Scottish Natural Heritage (also see BBC News Scotland).

A recent article in the New York Times describes how beavers are gaining approval in the Western United States as a defence against a drier and warmer climate. For example, the article points out that, “Beaver dams, it turns out, have beneficial effects that can’t easily be replicated in other ways. They raise the water table alongside a stream, aiding the growth of trees and plants that stabilize the banks and prevent erosion. They improve fish and wildlife habitat and promote new, rich soil.”  Although the return of beavers has many benefits, there are some negative effects, many of which it appears can be managed. However, for some people it may take 10 to 20 years to fully understand what beavers mean for arid environments.

Freedom of Information requested by Friends of the Earth (FOE) has uncovered that Public Health England (PHE) does not think that beavers pose a disease risk to human health. Alasdair Cameron from FOE said, “This new evidence completely undermines Government plans to remove Devon beavers from the wild”. Read the full story here.

Three recent papers published in the scientific press contribute to the debate about important issues surrounding beavers in Britain and their reintroduction. The first by Adrian Manning and colleagues (Manning, Coles, Lunn et al. 2014) reports on the use of radiocarbon dating techniques to date a wood specimen with beaver gnaw marks from Kielder Forest in the North of England to the 14th century AD. The authors say that this is, “the most recent radiocarbon-dated physical evidence of beaver yet found in Britain, by at least 400 years”. They go on to highlight the importance of not ignoring possible beaver signs when discovered and that this find strengthens the case for beaver reintroduction and restoration of riparian woodlands in the uplands. The other two papers by Helen Senn and co-workers (Senn, Ogden, Frosch et al. 2014) and Susanne Horn and co-workers (Horn, Prost, Stiller et al. 2014) concern the past and present genetic structure of Eurasian beaver populations. Susanne Horn reports that surviving relict populations of beavers are characterised by low genetic diversity and a strong phylogenetic structure (the relationship between evolutionary groups within the species). Helen Senn considers the nuclear and mitochondrial genetic structure in the Eurasian beaver from possible source populations for reintroductions to Scotland and the merits of the two approaches that are frequently of concern in reintroduction studies: to reintroduce beavers that (genetically) most closely resemble the animals that were historically present in the target area before they went extinct or to pick animals with low levels of inbreeding and high combined genetic diversity. The authors’ consideration of these two positions is detailed and interesting. They conclude, ” All else being equal, using a genetically diverse founder stock of a large number of animals, that is, monitored for inbreeding following release, represents the lowest risk genetic strategy for ensuring the long-term survival of the reintroduction”.

The full references can be found on the Bibliography page.

George Eustace MP (Parliamentary Under Secretary of State for Farming, Food and Marine Environment, and MP for the constituency of Camborne and Redruth in Cornwall) has replied to written question by Maria Eagle, the Shadow Environment Secretary, that, “We intend to recapture and rehome the wild beavers in Devon and are currently working out plans for the best way to do so…All decisions will be made with the welfare of the beavers in mind. There are no plans to cull beavers.” (see the Western Daily Press). To much public excitement and approval of the landowner, a family of beavers was spotted living on the River Otter earlier this year. It is not known where they came from, but the parents were probably escapees from a nearby reserve. These beavers are the first animals to have bred in England for several hundred years. The decision to remove them is controversial; many people would like the beavers to stay (see The Ecologist). Some are proposing that, providing they are of Eurasian origin and not carrying a particular type of tapeworm not found in Britain (Echinococcus multicularis), and with the approval of the local communities, they should be scientifically studied in a manner similar to the beavers released in the official Scottish trials at Knapdale, which ended recently. In this way, it is suggested, the environmental impacts of beavers on, for example, water quality, hydrology, flood alleviation and biodiversity in English rivers and wetlands can be properly assessed.

Jessica Aldred reports in The Guardian that scientists working on the 5-year trial reintroduction of beavers to Knapdale in Scotland, which finishes at the end of this month, have said the project has been an ‘outstanding success‘. Four groups of beavers were originally released between May 2009 and September 2010; they have successfully bred and there are now 13 animals living in and around four lochs. The beavers have built dams and lodges, dug canals and felled trees, thus changing the landscape. Many visitors have also been attracted to the area, boosting tourism and the local economy.

A pair of European beavers were released into a large secure enclosure in a 30 ha reserve at Blaeneinion near Machynlleth in West Wales in 2011. News and pictures/footage of the beavers can be found at the Blaeneinion web site and on Facebook.

The 5-year official trial introduction of beavers at Knapdale in Argyll, Scotland ends this month. As reported on BBC News Scotland, a YouGov poll commissioned by the Scottish Beaver Trial suggests that 60% of Scots support the reintroduction, whereas 5% are opposed. The Scottish government will decide next year whether to allow beavers to become reestablished in Scotland, and their decision will be influenced not only by the Knapdale trial, but also by the impacts of the population of ‘escaped’ beavers on the River Tay.

A sighting of a lone wild beaver on the River Otter in Devon, England was reported in July last year, and again last month at the same location. Now, a family of three beavers has been filmed on the River Otter (BBC News Devon; Mail Online; The Guardian). Although it is not known where they come from, the landowner, David Lawrence, is quite happy for them to be there. Tom Buckley, an environmentalist, has been filming the beavers as well as otters, which seem to be using the same bit of turf. Apparently, the Department for Food, Environment and Rural Affairs (DEFRA) has said that it is not lawful to release beavers in England, and they are considering what action to take – watch this space!

With some of the worst floods ever known happening across southern England, a question that arises is, “Could beavers ameliorate the extent and impact of flooding?“. As reported widely across the media recently (The Mammal Society; BBC News Magazine; The Telegraph; The Guardian; OurKingdom; Think to Sustain) the answer would appear to be yes, and in an economic way. For example, by building dams, storing water and slowing river flows in the upper reaches of catchments, beavers can help reduce flash floods and erosion. So, is it time to bring back the beaver to England and Wales? (See also news item posted on 16/7/12 below.)