How we added value
Habitat Survey & Design: Beaver enclosures
Before the re-introduction of beavers, the land near Okehampton was characterized by an area of dense willow scrub growing around a simple channel. A few years later, land within the beaver enclosure looks completely different: A mosaic of pools, shrub, dead wood and culm grassland is covered with colourful insects and flourishing wetland plants.
Biodiversity Valuation: the Biodiversity Quality Calculator
The Biodiversity Quality Calculator is developed by Dr. Alan Feest of Ecosulis. The calculator provides quantitative outputs based on a variety of biodiversity indices that are generated from biodiversity measurements and sampling efforts on the site.
Result: Biodiversity increase
Bryophytes (non-vascular plants like mosses), bats and aquatic invertebrates were used as indicator groups, as these species are most associated with beavers. In all these groups the number of species and the species biomass increased as a result of beaver introductions. Also, dominant species became less abundant, leaving space for rare species to enter the habitat.
Result: Change in nutrients
The pools that beavers create also act as nutrient sinks, in particularly for nitrogen. This was concluded after researchers discovered an increase in nutrient intolerant bryophyte species (non-vascular plants like mosses), that started to appear in the beaver enclosure.