Beaver lodges undergo a great many renovations in late fall. If the water level is high, the floor of the lodge and the roof of the sleeping chamber are raised. The lodge is strengthened with the addition of new material to the roof. Long, debarked sticks are pulled up vertically to the apex of the lodge and shorter sticks are then jammed into the lodge in order to pin it all together. When the roof of the lodge is two feet thick or more, mud and vegetation are applied on top of it.
Most of the decomposing plant material used to reinforce the roof of the lodge is dredged up from all around the base of the lodge (increasing the area’s water depth). The lodge is then coated with mud gathered at the bottom of the pond. This final coating of mud is of utmost importance – eventually it will freeze as hard as cement, providing protection from predators such as coyotes that can walk across the pond to the lodge once the water freezes. (A layer of mud is applied to bank lodges (see photo), as well.)
A beaver reaches all portions of the roof by holding the mud beneath its chin with its front feet, and walking upright on its hind legs, using its tail as a brace. The mud is then applied and smoothed over with its front feet. At the top of the lodge, an area about 15” wide is not coated, allowing fresh air to filter down into the roof of the sleeping chamber. On very cold winter days, the escaping moist warm air from the beavers’ breath can be seen drifting from this “chimney” at the apex of the lodge.
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