Distribution of Canadian Rocky Mountain Wetlands Impacted by Beaver

Abstract

Mountain wetlands, although limited in their spatial extent, provide many important hydrological and ecological services. There is a need to know existing beaver habitation patterns across mountain wetlands because of emerging interest in using beaver to restore and protect riparian and wetland habitats. However, there exist few inventories of wetlands, or their use as beaver habitat, for any mountain region of North America. We studied the distribution of beaver-impacted mineral wetlands and peatlands in a 7,912 km2 area of the Canadian Rocky Mountains. Using aerial photography and an existing wetland database, we inventoried 529 wetlands at elevations of 1,215 to 2,194 m; peat soils were found at 69 % of the 81 field verified wetlands. Wetland distribution and beaver habitation varied by physiography and jurisdiction. While 75 % of the wetlands identified were located in the foothills region, beaver were twice as likely to inhabit those in the mountain region owing to differences in land use activities and wildlife conservation measures. Wetlands inhabited by beaver had an order of magnitude greater area of open water and 12 times the number of individual open water features than those without. Beaver-enhanced open water extent has far-reaching consequences for wetland ecohydrological and biogeochemical functioning.