Once locked under the ice, beavers have only the food that they have had the foresight to store in their pond prior to it freezing to sustain themselves for the next four to five months. Sometime in September or October beavers start cutting down trees and limbing them. (The more northern the latitude, the earlier they begin this process.) Beavers have been found foraging over a third of a mile from their pond in the fall. At this time of year they tend to go further afield in order to find their preferred trees and shrubs – poplar, willow, alder and sugar maples. The branches are carried to the pond and hauled through the water to the lodge. When they approach the lodge the beavers dive down and push the butt end of the branches into the mud at the bottom of the pond and proceed to weave additional layers of branches into them.
Most caches are built as close to the entrance of the lodge as possible. A cache, or winter food supply pile, that feeds a colony of beavers consists of 1,500 to 2,500 pounds of edible bark, twigs and leaves. (On average, a beaver consumes 1 ½ pounds of food per day in the summer, and 2.2 pounds in the winter.) Because beavers don’t eat the wood, they must gather several tons of saplings and branches in order to have enough to survive.
If you look closely at yesterday’s close-up view of the food cache, you will see larger limbs on top of the pile. These larger logs are used to weight down the pile –they often consist of species that beavers aren’t particularly partial to, if they eat them at all. (Note proximity of food cache to the lodge, which is to the left in photo.)
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