Landscape influences on site occupancy by beaver and resultant foraging impacts on forest composition and structure (Adirondack Mountains, NY, USA)

This study combined an existing 30-year dataset of beaver presence with extensive field surveys at Huntington Wildlife Forest in the Central Adirondacks to investigate long-term drivers of beaver occupancy, and impacts of beaver foraging on forest composition and structure. Long-term beaver occupancy at a site was positively related to the landscape's capacity to support suitable habitat (terrestrial forage area), the available forest resources (deciduous basal area), and the site-specific costs required for wetland habitat creation and maintenance (dam volume). Forest structure and composition surrounding beaver ponds was also analyzed to determine gradients of beaver impacts with increased distance from the pond. Beaver showed a strong preference for stems 2-5 cm diameter, and for Acer pennsylvanicum. High densities of multi-stemmed Fagus grandifolia near the pond edge indicate a long-term structural effect on this species. Woody seedling regeneration was dominated by Acer spp. and is highest overall in the near pond environment.