Data for 'Are beavers a solution to the freshwater biodiversity crisis?'

Abstract

These are the raw data collected in Sweden in 2012. These data include data on aquatic plants, water beetles and supporting environmental information. Beavers create wetlands by damming streams in order to stabilise water levels, a by-product of this is the ponds they create are colonised by a diverse biotic assemblage. However, the biodiversity contribution of these beaver ponds to the landscape is unknown. In order to contrast and compare biodiversity of wetlands created by beavers (n=10) and other wetlands (n=10), we collected data on two contrasting taxonomic groups (aquatic plants and water beetles) along with supporting environmental information. Per wetland, plants were surveyed in 25 (2x2m) plots with plants identified to the highest taxonomic level and their percentage abundance estimated. Water beetles were sampled by sweeping a standard pond net through the water (over a 2x2m area) for 1 min with the majority of individuals identified in the field. This was replicated 5 times per site, giving a total sample size of 100. Several environmental variables were collected as they may explain potential differences between wetland types and biotic assemblages; the extent of leaf litter, open water, woody debris, bare ground and grazing associated with each plot or sample was scored visually on the 1–5 scale as above, while mean plant height and water depth were determined from 6 replicate measurements.