KNOWLEDGE BASE

Using 28 years of data, researchers developed two models to predict beaver colony density using different descriptors of beaver habitat. Key factors for higher beaver density included more hardwood vegetation, larger watersheds, and wider streams. These early models predicted colony density with 80% and 75% accuracy and were suggested to be able to help with land-use decisions, to minimise human-beaver conflict.

This article collects, analyses, and summarises a variety of fossil evidence relating to the evolution of mammals in a specific period of ancient history. This period is called the Late Cenozoic era, and is around the time that the modern horse became the species we know today. At this time, around 5 milion years ago, the first species of beaver emerged. Other species of large, beaver-like animals also roamed the planet. Please note, this resource is not open-access.

This classic study in Québec, Canada showed how beaver dams impact nitrogen cycling in streams. The dam increased sediment accumulation and the amount of wet land in the area, leading to more nitrogen accumulation and changes in nitrogen processes. For example, after damming, nitrogen fixation by microbes became more intense. Overall, the beaver-modified area accumulated over 100 times more nitrogen than before the beavers arrived. This study has shaped our understanding of nitrogen cycles in beaver streams. Please note, this resource is not open-access.

In 1973 in a National Park in the USA, scientists measured plants to better understand beavers' foraging patterns. These beavers had a strong preference for certain plant species such as birch, irrespective of how far from the water they were. However, beavers did forage less when further away from the water. The scientists used this data to test their understanding of the logic behind beavers' foraging behaviour, showing that their model - adapted from that of moose foraging - appeared to make accurate predictions.

This study challenged common beliefs about beavers' social organisation. By studying beaver colonies in two parts of the USA for two years at a time, it found that beaver colonies could have multiple adult members of either sex and that there was frequent movement between colonies. The authors suggested that such features may be related to the high population densities of beavers in the area. Please note, this resource is not open-access.