I drive by a few beaver lodges each day on my way to and from work. When I pass by the lodges, especially now after ice-up, I often wonder what they are doing. They are probably snoozing.
Beaver lodges are two tiered living quarters with two entrances. A small lower level functions as an entryway and dining room. The upper level is used for resting and sleeping. These lodges are surprisingly well insulated, with the internal temperature hovering slightly above the freezing point even when the outside temperatures are much colder.
The occupants of the lodge generally consist of a family unit, parents and the young of the summer. During the fall, there is generally a noticeable accumulation of cut branches visible in the water near an occupied lodge. That is the beaver’s food cache for the winter. During the fall, they keep busy cutting nearby aspen and willow branches and pushing the larger ends of the branches into the sediments to anchor them in place. Eventually there is a large cache of these branches, some of which may become frozen into the ice.
During the winter months, the beaver will feed from the cache, probably daily. However, they will spend most of the time just resting or sleeping, often huddled together to conserve energy. If they have put on some much needed fat going into the winter and have enough food cached, they will make it through to spring in good condition.
Speaking of getting through the winter, in a Natural North Dakota a couple weeks ago I summarized Ron Pittaway’s winter finch forecast. He predicted that because of good seed and fruit production in the forests across eastern Canada the finches would probably not move southward this winter. So I was rather surprised to see some evening grosbeaks in our yard recently.
Out of curiosity, I did a quick computer search of the forest fires in Manitoba last summer. As of mid-September, fires had burned over 650 square miles of Manitoba’s forests.
So perhaps the forest fires in Manitoba have reduced the food supply for finches enough to cause some of these birds to move southward in search of food. It will be interesting to see what will show up here this winter. But one thing is for sure. Keeping some bird feeders well stocked with sunflower seeds will increase our chances of getting to see them if they do come down.
Natural North Dakota is supported by NDSU Central Grasslands Research Extension Center and Dakota College at Bottineau, and by the members of Prairie Public. Thanks to Sunny 101.9 in Bottineau for their recording services.