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Message: Beavering The Canadian Landscape Photo from www.timna.mines.com When I think of the forces that formed the Canadian landscape, I think of glaciers carving away billions of tons of precambrian rock. Georgian Bay’s serpent-like islands of orange and red stone remind us of the sculpting power of ice and water. Surprisingly, though, the forces that gave Canada its unique forests and water-created landscape not only include glacial ice: they include the innocuous beaver—or, at least, 200 million beavers. This insight comes from a remarkable book titled, “Water: A Natural History,” by Alice Outwater. The author makes a compelling case for the subtle, natural ecosystems that shape the landscape. A cornerstone of that natural system was Castor canadensis, or, for the rest of us, the beaver. When Europeans first arrived in North America there were more than 200 million beavers living here. Take a look at the above picture. This dam and the small lake it creates are the work of one small clan of beavers. Say it is the effort of ten beavers. That means there probably were at least some 20 million similar ponds and streams across the land. While that is impressive, the real impact of the beaver’s skilled hydro-engineering is the ecosystem it created. According to Outwater, a beaver family can build a 35 foot dam in one week. Some dams extended up to 4,000 feet in length. As interesting as that is, the real importance of the beaver’s work is its profound impact on the ecosystem. Their work creates a transition between two diverse conditions: water and land. In environmental terms this is known as an ecotone. Ecotones are home to organisms native to each environment - land or water - as well as organisms native to the ecotone itself. That in-between zone is called the “edge effect.” What is remarkable about the ecotone is that it creates habitats for a diverse array of wildlife from frogs, to herons, to raccoons. From the micro ecosystem perspective, the wetland creates millions of organisms many of which are microscopic in size. Planktonic communities abound here. They, in turn, provide food for organisms higher up the food chain. Wetlands made this way are remarkably effective water filtration systems. They also even out the highs and lows of the water supply, keeping water available during droughts and slowing down potential floods. Also critical to this eco-chain is that the beaver ponds allow water to filter down into the local water table. That means more clean water is available in the form of springs. The market-driven demand for beaver pelts to make hats in Europe almost eradicated the beaver. Now they are considered a novelty or a pest. In fact, they were an engine of our ecosystem. Their loss will, according to Outwater, have ramifications we are only now beginning to understand. www.corporateknightsforum.com