KNOWLEDGE BASE

Beavers, through dam-building, restore ecosystems: they are an increasingly common climate adaptation strategy. This study constructed a model to predict where beavers may be likely to settle across 5,000 km of rivers and streams in the USA. The model was based entirely on remote data but was checked with on-the-ground surveys. Existing patterns of land use and land ownership (such as by large, private timber companies) may limit restoration efforts.

This study sought to understand what factors come into play when beavers in British Columbia, Canada, decide where to settle down and build their home. Here, habitat quality was the main driver for beaver presence. They preferred areas with richer vegetation, more open water, and lots of swamp. Predation risk and human activity did not seem to affect their decision.

When undergoing stream restoration in Europe, the aim was typically to try to recreate a single, meandering channel with a silt-clay floodplain. This paper, by exploring a variety of historical data, showed that this aim is not appropriate to the European context. Major European rivers actually used to be multi-channel systems, choked with vegetation. The text described how these systems were transformed over millenia through deforestation, farming, and other human activities. Restoring to this historical state is impractical, but examples of beaver reintroductions are described in detail as promising approaches for European river restoration.

This paper analysed DNA from beaver fossils. It aimed to reconstruct how beavers migrated and evolved over time in Europe. This helps inform today's conservation decisions by understanding which populations were in Britain before they were hunted to extinction. British beavers were part of a large group of western European beavers who all shared similar DNA.

In Canada, scientists counted how many beavers a wolf was hunting. Scaling up from this individual, they estimated that the local wolf pack killed around 80 beavers during the ice-free season (around one beaver per wolf, every ten days). This was around 40% of the local beaver population, yet the beaver population increased by around 40% that year, possibly due to migration from nearby areas.