The impacts of beavers Castor spp. on biodiversity and the ecological basis for their reintroduction to Scotland, UK

Abstract In Scotland, UK, beavers became extinct about 400 years ago. Currently, two wild populations are present in Scotland on a trial basis, and the case for their full reintroduction is currently being considered by Scottish ministers. Beavers are widely considered ‘ecosystem engineers’. Indeed, beavers have large impacts on the environment, fundamentally change ecosystems, and create unusual habitats, often considered unique. In this review, we investigate the mechanisms by which beavers act as ecosystem engineers, and then discuss the possible impacts of beavers on the biodiversity of Scotland. A meta‐analysis of published studies on beavers’ interactions with biodiversity was conducted, and the balance of positive and negative interactions with plants, invertebrates, amphibians, reptiles, birds, and mammals recorded. The meta‐analysis showed that, overall, beavers have an overwhelmingly positive influence on biodiversity. Beavers’ ability to modify the environment means that they fundamentally increase habitat heterogeneity. As beavers are central‐place foragers that feed only in close proximity to watercourses, their herbivory is unevenly spread in the landscape. In addition, beaver ponds and their associated unique successional stages increase habitat heterogeneity both spatially and temporally. Beavers also influence the ecosystems through the creation of a variety of features such as dams and lodges, important habitat features such as standing de...
Source: Mammal Review - Category: Zoology Authors: Tags: Review Source Type: research