KNOWLEDGE BASE

This report assessed the status of beaver populations in the Rocky Mountains, USA. Despite the pressure of habitat destruction, populations appeared to be stable or growing. Improved trapping regulations, habitat protection, and population restoration efforts had helped. The report acknowledges the damage that beavers can cause in some areas, but says that their presence is usually desirable because of their ability to maintain healthy ecosystems. The report says that conservation efforts should focus on protecting habitats and pro-actively managing any damage issues and human conflicts.

This text discusses the management of an ecological reserve in California, USA. In this case, beavers were suspected of harming endangered songbirds and facilitating an invasive plant. This suspicion was not based in scientific evidence and, indeed, the scientific evidence suggested that the opposite was true. Nevertheless, a programme was started which permitted beavers' 'removal,' leading to unnecessary beaver deaths. The text highlights the importance of using scientific evidence for decision-making in reserve management.

Cladocerans are small, freshwater crustaceans which fish feed on. This study shows that beaver ponds support a greater diversity and abundance of these animals than free-flowing riverwater or water behind man-made dams. Females of a specific cladoceran species produced more offspring in beaver pond water than in river water. The authors note that this is not only due to how fast the water is flowing but also nutrients in the water.

In Scotland, there is a debate about reintroducing wolves to control red deer populations which impact forests and farming. Simulations suggest wolf reintroduction could benefit conservation by reducing deer numbers and cutting the costs of deer control. Public opinion generally supports wolf reintroduction, although farmers have concerns. A small proportion of respondents to the survey said they preferred the idea of re-introducing other species such as beavers rather than wolves.

This article sets out the importance of headwater streams (those near the source) for river biodiversity. The article mentions that beavers may frequent headwater streams but takes a much more general angle overall. They look at three headwater streams in the USA and highlight that over 290 species exist there.