850 m (2,790 ft), Wood Buffalo National Park (Alberta, Canada) – The world’s longest known beaver dam was discovered with Google Earth on October 2, 2007. Satellite photos from the 1990s and 70s indicate that the dam was constructed by successive generations of beavers starting sometime after 1975. Because this part of Wood Buffalo National Park is flat, the beavers had to build a long dam to contain the wetland waters. A typical beaver dam stretches less than 100 m (328 ft).

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EDITOR’S NOTE
One second after I took the last photo in the gallery below, I had to fend off the fully-grown and very irate adult as it raced for my head with its jaws wide open and its razor-sharp incisors glittering in the greenish sun of the Cap-Chat River. For the first time in 30 years of diving, I let out a scream both out of fear for myself and out of concern for the beaver that was rightfully defending its colony, i.e. family, and lodge. The flash attack by the 40-pound ball of teeth and claws was as violent as it was unexpected. The furry torpedo rammed into my camera which then smashed into my face. The force of the impact tore off my spotting light and flooded my mask. I beat a quick retreat back to shore where the beaver followed in pursuit. No injuries were apparent on either of us before the proud defender headed into the bushes where it felled a small tree and started munching away as if nothing had happened… This incident reminded me of a recent debate to have the polar bear replace the beaver as Canada’s emblematic animal. Because of its hardworking nature and in light of its resolve to fight only when its survival is imminently threatened, even against an unknown creature five times its own weight, the beaver will always have my vote!