KNOWLEDGE BASE

The research uncovers a way beavers shape landscapes by creating meadows. In the USA, beavers built a dam in a river, triggering a flood which drowned vegetation, leaving only hummocks untouched. Sediment accumulated along the flood's path and remained after the dam broke. This sediment, raised above future floods, supported new vegetation growth, forming diverse meadows. This study expands our understanding of how beavers influence valley ecosystems. Please note, this resource is not open-access.

In this article, researchers report on attempts to work out how beaver dams influence ecosystems downstream. They looked at 12 beaver ponds over two years, one very wet and the other very dry. They found a number of impacts but none of them consistent, depending not only on the size of the dam but also the size of the pond and water levels more broadly. The authors note that the knowledge gathered about human-made lakes and ponds is of limited use when trying to understand beaver ponds.

This study explores the evolutionary history of beavers by studying the genes of both living beaver species. The scientists found that beavers are closely related to scaly-tailed squirrels, who may have diverged from other rodents around 54 million years ago (mya). The divergence between North American and Eurasian beavers probably occurred over 7 mya, possibly due to migration from Eurasia to North America. Finally, they find that the last common ancestor of all the Eurasian beaver populations probably lived much earlier than thought, around 210,000 years ago.

The study in the French Ardennes region compared the ecological needs of three aquatic rodents: the invasive coypu and muskrat, and the protected European beaver. Coypus and muskrats were found in various habitats while beavers preferred wider waterways with specific woody plants. The findings suggest potential settlement areas for each species, but more data for beavers is needed for conclusive management decisions.

This report set out the reasons for, and feasibility of, reintroducing beavers to Wales. It describes beavers' ecology as well as its current legislative and reintroduction status across Europe. The authors also set out potential sources of conflict and mechanisms for managing those. A trial re-introduction is proposed, including ideas for funding and an exit strategy.