大象传媒

While beavers can get around perfectly well on land they are most at home in the water because they have webbed hind feet and a large paddle-like tail. Beavers feed on all kinds of vegetation and eat wood as well as leaves. The large ponds they live in, such as one in the Teton Mountains in Wyoming, are entirely their own creation. Only a few years ago it was a shallow stream flowing straight down the valley, then a family of beavers moved in and built a dam. The lake they created is lined with logs of all sizes as well as mud and vegetation. To within a few inches, it is horizontal across its entire length of about 150 yards, and the lake is has created stretches upstream for almost a mile. If they detect the slightest leak, they will start repair work immediately, bringing new logs and mud. Keeping the water at a high level means that the beavers can swim in safety to their main source of food. They dig channels that lead them right into the heart of the surrounding woodland where they can nibble at fallen tree trunks in comparative safety should a bear or a mountain lion turn up.