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 5 abandoned beaver house DHJanzen100878.jpg high resolution
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| A beaver house in summer. No ripples of a swimming beaver break the water in the pond. Is there indeed a beaver family in this pond? At first glance, you know that this beaver house (and its pond) has been abandoned. Why? Because there is vegetation growing on it. Beaver are continually massage/mix and replace the mud and sticks on their houses (some of which erodes off through rain, and through sloughing of rotting structural parts), and in doing so reduce the surface of an active house to mud and sticks. Plants that germinate there are quickly dislodged and trampled. Another clue to unoccupancy is that the mud has largely been eroded away by rain, leaving mostly sticks on the upper surface. Third, and more subtle, is that just above the lily pads on the lower right, one of the entrance tunnels is visible just above the water line. When a beaver house is constructed, the entrance/exit tunnels are placed 6 inches to 2 feet below the waterline. An exposed tunnel means that the level of the pond has fallen, which in turn means that the dam (see image DHJanzen100879.jpg below) is not being carefully maintained, which it would be if the house/pond were occupied. | ||
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