Beaver Impacts

Public Perception

Throughout Europe beaver re-introduction has proven popular. In 2004, at a public debate on re-introductions held at the Natural History Museum in London, the beaver received overwhelming support from the audience.  In 1988 Scottish National Heritage (SNH) carried out extensive national consultation on the desirability beaver reintroduction. Three types of survey were undertaken during the consultation:

  1. In a ‘passive public’ opinion survey involving 2,141 interviews, 63% of the general public supported a re-introduction, 12% were against, and 25% had no view.
  2. A total of 1,944 written responses were received during a ‘pro-active public’ survey. Overall, 86% of this sample was in favour of the re-introduction. A smaller majority of land managers and those with interests in forestry supported re-introduction. However there was a lack of support from those with interests in fishing and agriculture.
  3. A total of 281 consultees were also approached of which 144 (51%) responded. Reactions were mixed. Conservation and academic sectors were the most supportive, fishing/angling interests were the least supportive.

The outcome of this consultation was subsequently placed in the public domain for discussion. The consultation demonstrated that a majority of the public were in favour of a re-introduction.

Beaver impact on biodiversity
Beaver are a keystone species that enhance wetland habitat, reduce down-stream flooding, silt runoff and diffuse pollution in major water courses. Coppicing of bank side vegetation by beavers is cost effective and sustainable. This activity increases the biodiversity value of wetlands for plants, insects, fish, amphibians, birds, and mammals.
Habitat formed by beaver activity is vital for a wide range of species such as:

  • Mammals – otters, water voles, water shrews and bats
  • Insects – dragonflies, aquatic invertebrates and species preferring marsh or wet woodland
  • Reptiles and amphibians – grass snakes, newts, frogs and toads
  • Fish – ponds and channels increase habitat and food for fish, increasing biomass and species diversity. Ponds provide refuges for fish in drought condition
  • Birds – creation of breeding or feeding habitat and the provision of refuge areas for a wide range of species
  • Higher Plants – creation of a wide and dynamic variety of wetland habitats which increase the diversity and abundance of plant species.

At a minimum beaver grazing is likely to contribute to 3 UK BAP priority habitats and 3 UK BAP broad-habitat type action plans. Beaver grazing could sustainably benefit in excess of 12 UK BAP priority species. Beaver dams and channels may contribute to actions in up to 31 priority species action plans. There have been two well publicised projects in England where beavers are employed as habitat mangers. The first of these began in 2001 at Kent Wildlife Trust’s Ham Fen Nature Reserve, while the second in 2005 at the Lower Mill estate in the Cotswold Water Park was undertaken by Conservation Builders Ltd.

Beaver impact on fisheries
European beavers have a positive effect on coarse fish populations and a neutral relationship with game fish. It has been suggested that beaver dams in the head waters of Scottish salmon rivers would destroy spawning beds. Although this is a debateable contention, it is true that beavers can build dams from rocks. Experience from Norway where a healthy, wild salmon population exists demonstrates that they can readily leap beaver dams to spawn in the waters above.

Beavers typically have a positive impact on fish populations by maintaining river levels and water flow as well as creating new spawning pools. In times of drought beaver pools act as significant fish refugia. Beaver felled timber in water courses can afford fish fry protection from predatory birds such as Cormorants (Phalacrocorax carbo) and Goosanders (Mergus merganser). The significantly higher populations of aquatic invertebrates generated by the submerged timber provide a larger prey base for fish. Beavers generally prefer slow-flowing rivers rather than the fast-flowing streams used by salmon and evidence from Norway suggests that there are few if any adverse impacts to salmon fisheries caused by beaver dams. Dams do not impede the passage of fish, and they do offer protection to fry.

Beaver Impact on Agriculture and Forestry
Beaver activity has an insignificant impact on commercial forestry and agricultural practice. Conifers are not normally eaten and beaver grazing on specific specimen trees can be easily prevented by simple wire mesh fencing. Undesirable, localised beaver activity can be simply resolved by a range of proven continental or North American methodologies such as dam drainage or exclusion fencing. Dams are not be protected by law and can therefore be removed by landowners in case of conflict. Where this is not practicable beavers can be easily trapped on their regular runways and translocated or culled.

Flooding of farmland is a relatively easy issue to resolve by the drainage of dams, their removal, the translocation of beavers or their humane culling when this is no longer possible. In lower Bavaria the annual cost of beaver activity to the public purse has been calculated to equate to significantly less than the average daily cost of damage caused by other game species. Swedish experience demonstrates that the impact of beaver grazing on commercial woodland is considerably less significant than deer whilst in Norway (Beaver population about 50,000) foresters have determined that the level of damage caused by beavers is insufficient to warrant insurance.

Economic benefits of beavers
Wildlife tourism is a rapidly growing sector of the economy. This is recognised by government, tourism and economic development agencies. The reintroduction of a charismatic species such as the beaver which can be watched at dusk and dawn would provide a significant selling point. Evidence from a trial re-introduction in Denmark showed a substantial increase in visitors to the first release site. In Norway, Holland and France guided beaver walks have become an established part of the wildlife tourism industry.

The introduction of beavers into an enclosed Lake on the Lower Mill Estate in the Cotswold Water Park, England, generated world wide publicity and a high level of ongoing interest both from the residents who own properties on the Estate, potential buyers of second homes and the general public. This site is not open to the public but has demonstrated a considerable demand for opportunities to see beavers in the wild. Beavers are popular with the general public and could afford the development of green-tourist business. Another economic aspect is the immense potential for beaver activity to deliver a significant economic benefit, in relation to the retention and purification of the national water resource. The ecology of this species, its requirements and activities are entirely compatible with the incoming EU water framework directive. Beaver damage in the whole of Bavaria is currently estimated to amount to a couple of hundred thousand euros per year and is easily managed. In stark contrast car insurance companies pay at least 35,000,000 euros annually for collisions with game species.