KNOWLEDGE BASE

This study investigates how beaver dams affect stream flow in southwest England. Using data from before and after beavers occupied the area, they found that beaver dams at this site increased the time between peak rainfall and peak stream flow, and reduced the frequency of high flows. In other words, beaver dams reduced flood risk at this location. This was mainly achieved by increasing the capacity for the floodplain to store water.

For humans who make a living from felling timber, beavers can be a nuisance species. This study explored Eurasian beavers' foraging behaviour in different types of forest in the Czech Republic: monoculture, mixed, and natural. Beavers preferred non-commercial species like willow and poplar. However, in commercial forests where those weren't available, they also felled oaks - especially younger trees. The authors suggested that economically valuable species like oak could be protected by adapting forest management approaches. For example, by increasing the availability of willow near the water's edge.

In Polesie National Park, Poland, scientists examined how Eurasian beavers affected vegetation diversity and the spread of non-native plants. Beaver activity increased the diversity of plants at the forest floor and in the canopy - but not really in between, and only near the watercourses. The results also showed that beavers indirectly supported the expansion of invasive species such as devil’s beggartick and giant goldenrod.

Beavers once lived in Greece but had disappeared by the 19th century. In 2021, a project was launched to reintroduce them, led by experts from Greece, Europe, and the Beaver Trust in the UK. This poster described some of the progress made: feasibility studies had found suitable habitats, and efforts to promote the project had included meetings, building a social media presence, and outreach in traditional media.

This commissioned report is a case study of how BMGs are forming around the unofficial beaver populations. The report draws upon findings from a previous study that captured the experiences of stakeholders involved in governing the River Otter Beaver Trial and explores the applicability of those findings to the River Tamar.
Rather than being a fixed governance structure therefore, Beaver Management Groups themselves are a process, that seeks to facilitate renewed coexistence between humans and beavers in catchment settings.