FAQ: Do beavers build dams?
Beavers are well known for their construction skills. They tend to build dams when their habitat does not provide all the conditions suitable for a beaver's needs. Beavers feel safe with water around them and so to ensure their safety, a beaver may construct a dam in order to create deeper ponds on which to build their lodge, and/or to enable water access to food resources. Eurasian beavers often create smaller dams than their North American counterparts, on smaller tributaries rather than broad, fast flowing rivers.
Knapdale Forest was chosen as the location for the Scottish Beaver Trial as it features a range of habitats suitable for beaver activity. When beavers do dam, this modification can have a positive effect for biodiversity. Their ponds benefit many species including otters, water shrews, water voles, birds, invertebrates (especially dragonflies) and breeding fish. Dams can also hold water in periods of drought, can regulate flooding and improve water quality by holding silt behind dams and catching acidic and agricultural run-off.
The beaver: keystone species of wet woodland and forest
More FAQ's - Beaver basics: basic beaver ecology