At the same time, populations of beaver (Castor canadensis) have been recovering from past near-extirpation. Wetlands cover more than 20% of the area in boreal Alberta and provide critical habitat for a variety of wetland-dependent wildlife such as moose, muskrat, waterfowl, and other birds. Beavers build many of these wetlands but their impacts have never been studied in northern mixedwood forests.
Where roads cross streams, they sometimes block flow and create upstream ponds or raised water tables, and lower water tables downstream. This effect might be similar to what happens naturally at a beaver dam. Unlike beaver dams, however, roads are essentially permanent features of the landscape - they may be changing riparian areas in ways that differ from the impacts of beaver activities.
This study addressed these questions:
I conducted detailed vegetation surveys on six streams with a paired road crossing and beaver dam.
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