Mapping beaver infrastructure in the Karelian part of Vodlozersky National Park using aerial photographs

This study was conceived to investigate the potential capabilities of aerial photography in mapping the distribution of beaver colonies and beaver-induced changes in waterside forest stands. The article analyzes aerial images from the Karelian part of the Vodlozersky NP taken in 2015–2016 within a forest management inventory. The analysis covered 84 colonies, of which 31 % (n=26) were inhabited or recently abandoned and 63 % (n=53) were abandoned. The habitation of 6 % of the colonies is questionable. Dams were spotted in 71 colonies (84.5 %). In 37 colonies we managed to spot and map 41 active or overgrowing beaver ponds. The area of flooded or flood-killed forest was 0.2 ha at minimum, 46.5 at maximum, and 13 ha on average