When people from North America think about beavers they are generally thinking about North American beavers (Castor canadensis), but there is another species of beaver that is native to Europe and parts of Asia, the Eurasian beaver. Eurasian beavers are a topic of debate in the United Kingdom. Many want to reintroduce the species but there is also a lot of people against it.
Eurasian beavers do not grow as large as their North American counterparts and are a rare example in mammals where females may actually grow larger than males of the same size. They are also Europe's largest native rodent. Eurasian beavers have been extinct in the wild for hundreds of years in Britain with some of the last populations found in Scotland in the 1800's. Beavers were hunted for their pelts as well as their castor glands that produce castoreum. Castoreum is a secretion that the beavers use in scent marking but humans decided to use it in medicine to relief headaches. It has also been noted that Eurasian beavers are less aggressive and build fewer dams and build them in shallower water than their North American relatives.
Eurasian beavers have been kept on private lands for a number of years, but the first reintroduction by a government agency started in 2009 when the Scottish government released 16 beavers in four family groups into Knapdale Forest. Several private trusts and foundations have established areas that they release beavers into including areas near Devon and the Cotswold Water Park. Wild sightings of beaver have also been spotted near Devon and it was determined that they had not escaped from the nearby enclosure and had successfully reproduced. There is also a population in Scotland at Tayside and it is believed that these beavers came from private collections. In all of these areas beavers are currently being allowed to remain by government agencies and are monitored to see their impacts.
There have been positive and negative impacts of the beavers. It has been found that beavers have had a great impact on the local environments. The dams they create act to slow down rivers and mitigate local flooding. Slowing down the rivers also reduces erosion. The beavers have also increased local species by providing more suitable habitat for otters, dragonflies, waterfowl, other birds, and amphibians. Beavers also increase plant biodiversity by removing trees and flower will grow their inviting insects.They also stimulate more tree growth when they remove some of them. By increasing wetland areas the wetlands are able to filter out more pollutants as well as decrease the amount of silt moving down river.
The beaver also worries people about having negative impacts. One group of people that have concerns are the farmers. The farmers are worried that the dens in the banks of the rivers will cause the ground under their farms to collapse and they are worried that the beaver dams will flood their fields. It should be remembered that these beavers build dams more infrequently than what is thought. Farmers are also worried about disease transmission to their livestock, but none has been found thus far. The anglers of Britain are also worried about the impacts of beaver on migrations of salmon and eel. It has been shown in other European countries where these animals all coexist that the beavers do not hurt fish migrations and actually help them by providing more safe spawning areas. Their is also a misconception that beaver eat fish, but this is not true.
I believe that their has been sufficient evidence to show that beavers can thrive in Britain if they are given some initial protections and allowed to remain. I think reintroduction of an extirpated species is a great idea and we should try to do what we can to restore environment to a balanced setting.
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