Spatiotemporal changes in biodiversity by ecosystem engineers: how beavers structure the richness of large mammals

Abstract

High levels of biodiversity may be needed to maintain ecosystem functioning. By creating niches for other species, ecosystem engineers have the potential to promote biodiversity, but it is unclear how this translates across spatiotemporal scales. We evaluated the long-term impact of ecosystem engineering by beavers (Castor canadensis) on the diversity of mobile species. We tested the hypothesis that the spatial distribution of engineered habitats in different states resulting from ecosystem engineering by beavers increases the biodiversity of large mammals across spatial scales. We tested a second hypothesis that engineered habitat in different states resulting from ecosystem engineering by beavers drive the diversity of large mammals. We compared the richness and composition of boreal mammals using camera traps between habitats with and without history of occurrence by beavers within a protected area, where trapping, hunting, and forest exploitation are prohibited. We found that unique species were mostly found in specific engineered habitats, with ponds and wet meadows showing more species than dry meadows. In addition to the increased diversity of dispersal-limited species, our results show that beavers promote the diversity of mobile species at both local and landscape scales, signaling the importance of niche creation in structuring animal communities across scales.

Human-beaver cohabitation in the Early and Mid-Holocene of Northern Europe: Re-visiting Mesolithic material culture and ecology through a multispecies lens

“…Nummi and Hahtola, 2008;Nummi and Holopainen, 2014;Nummi and Poysa, 1997) and have been shown to increase localized mammal richness (cf. Gauvin et al, 2020;Wright et al, 2002). Beavers coregulate biodiversity, often locally increasing it (Law et al, 2019;Stringer and Gaywood, 2016), and they typically complexify ecological networks and interactions where they are active in the landscape (Naiman et al, 1986).…”

Wood Jams or Beaver Dams? Pliocene Life, Sediment and Landscape Interactions in the Canadian High Arctic

“…The number of retrieved The presence of beaver dams in the succession may provide explanation for other paleoecological characteristics of the High Terrace Deposits on Ellesmere Island, and could suggest that the apparent convergent evolution of dam-building within Dipoides had a significant ecological impact. The high biodiversity of fossil remains could reflect increased habitat heterogeneity/niche availability and animal behaviour around dams increasing the presence and density of other large mammals in the area (Hood and Larsen, 2014; Stringer and Gaywood, 2016; Gauvin et al, 2020). Similarly, the presence of beaver dams is known to promote the availability of deadwood and encourage invertebrate populations (Mourant et al, 2020) and could explain the abundance of woody debris recording beetle galleries (Figure 7).…”