KNOWLEDGE BASE

This study explored the genetic diversity of beavers in Finland, Lithuania, Estonia, and Russia. After extensive hunting and some reintroduction efforts, the researchers thought that historic population bottlenecks may have led to low genetic diversity. Finnish beavers had the lowest genetic variability, which may be harmful to the overall beaver population. Introducing beavers from elsewhere may improve their future prospects.

This text recounts the history of beavers in Poland, from medieval times to World War II to the modern day. Today, beavers can be found all over Poland and the population is stabilising, but they are causing some conflicts with farmers and foresters. The genetics of Poland's beaver population and possible management options are discussed.

This paper compiled unpublished data on the historical presence of Eurasian beavers in Bulgaria, from ancient times to the 19th century. It described beavers' distribution across different regions and altitudes - most beavers were located in lowland areas near rivers, with evidence suggesting a decline after 2,000 years ago until the last record of beavers in around 1800.

The impact of beaver dams on habitats and water quality is widely acknowledged, but their role in flood control had been under debate. This study entered that debate by using a computer model to assess how beaver dams impact on flooding in Germany. The results suggested that, while dams did influence the flow of water, they didn't significantly reduce flood peaks for larger floods. The authors conclude that beaver dams are not effective flood mitigation measures.

This fascinating experiment exposed beavers to scent marks from distant neighbours (two territories away) and strangers to test how they responded. The results showed that male Eurasian beavers show more aggressive responses to sub-dominant distant neighbours than to strangers. This was likely in recognition of the higher threat they pose (e.g. repeatedly intruding on the male's territory as they try to disperse). Other results are described in the text but, overall, the experiment highlighted the high sensitivity that beavers have to the familiarity and social status of intruders. Please note, this resource is not open-access.