The Dam, the Myth, the Legend: 50 Years of the Beaver

On March 24, 1975, the beaver became the official symbol of Canada by royal assent. It’s been 50 years since the squat, toothy animal achieved national status. While sometimes deemed a nuisance for downing trees, their unparalleled construction skills have reduced flooding damage during times of unprecedented rainfall. Today, this industrious rodent-engineer seems to have become a symbol for much more, having bounced back after being hunted to near-extinction at the beginning of the 20th century.

But another beaver skillset is equally important: they excavate pond bottoms and dig canals into the surrounding landscape. “In certain types of wetlands, they dig kilometres of canal systems,” says Hood. When there’s rain after a drought, it’s these canals that bring the water.

At the other extreme, these same beaver-engineered landscapes also show a capacity to reduce severe flash floods caused by intense rainfall. In 2013, when Calgary suffered its worst flooding in over a century, Cherie Westbrook, an ecohydrology professor at the University of Saskatchewan who had been doing field work in the Kananaskis region, discovered it could have been even worse were it not for the beaver dams upriver from the city. Despite the deluge, roughly seven of every 10 of those dams upriver remained intact and were still holding back water after the storm.