Survey of distribution of beavers in Tayside in 2012

Quality Control

There is a high degree of confidence - all signs were noted by experienced surveyors. However, areas where no recent beaver activity had been found in previous surveys within the preceding year were omitted from the survey. Because the field survey was carried out in late May to early July, summer vegetation may have hidden some signs of beaver activity during the survey.

Method steps

1. Rivers were surveyed from open canoe or on foot. All signs of beaver activity observed were logged on a GPS. All signs subsequently identified within 10m of riverbank from the first identified sign were logged under the same GPS waypoint, thus GPS waypoint data has a linear resolution of 10m. If signs were located over an area >10m in riverbank length, a new GPS waypoint was logged every 10m until no more signs were identified.

The survey covered the River Tay Catchment, including the Rivers Tay, Tummel, Garry, Earn, Isla, Ericht, Dean Water, Baikie Burn, Lunan Burn and their tributaries. (No beaver signs were found in the Garry.)