A beaver lodge is one of the classic shapes in nature. From a distance its conical outline is unmistakable. On closer look, that this conical shape is made with a myriad of logs cut by the beavers adds to our high estimation of the building skills of the beaver. In her book, Lily Pond, Hope Ryden cites evidence that the beaver's lodge building skills are inherited, that "stereotypical motor sequences used in the construction of dams and lodges are expressed spontaneously by each individual" beaver as it matures. No wonder beaver lodges look so much alike.
That said, I can think of exceptions, some eccentric touches to the iconic design, especially the tendency for lodges to have some rather sharp logs stabbing out from the top of that classic cone shape. In most cases it is hardly noticeable. In my web page on beaver lodges, I wanted to use my most typical photo of a lodge, and chose this one:
I forgave that ragged look on top perhaps because it reminded me of my uncombed hair when I was a kid. Both the lodge and my haircuts were unremarkable manifestations of life's messy ends that need not mar its underlying perfection. I probably should have chosen one of my many photos showing a tamer beaver lodge, like this one.
Then I saw the lodge the photo of which graces the top of this blog. Here is another view of that lodge taken after a snowfall that emphasizes its eccentric top:
I had a long familiarity with this lodge before I saw that log sticking up out of it like a flag pole. Sometimes beavers will build a lodge around a tree, but not in this case. Here is how the lodge looked two months before it became the beaver version of the Iwo Jima Memorial:
That photo was take February 6, 2005. I saw the log sticking out of the lodge in April. My immediate reaction was that a human did it. During hunting season the previous fall, someone dug a hole in the dam. The beavers repaired it promptly and through out the winter and early spring there was no other vandalism that I noticed. There were no other signs of a human, other than me, being around. There were signs, just before the pole went up that otters returned to the pond.
I have been fortunate in being able to observe ponds that both beavers and otters share. Over the years I've taken many videos of otters on top of beaver lodges. Here are 6 otters on another lodge in the same pond taken a few years earlier.
I know that it is widely believe that otters eat beavers but they don't. Please don't use my photos and observations to argue that beavers are afraid of otters. They aren't. And I am not sure that beavers worry that much about otters lounging and scatting on top of their lodges. Not that the beavers think otters are especially cute when they are on top of a lodge, which might be your reaction to the video from which I lifted that photo of the 6 otters.
Some beavers seem to go to great lengths to keep otters from getting into the top of their lodge. Beavers need to vent air from the lodge and usually that vent is at the top where the logs used to build the lodge meet or crisscross. But I've noticed that often the loose construction at the apex of the lodge can result in a small chamber that's not of much use to a beaver. This is especially the case in large lodges that can lose that neat conical shape and tend toward the profile of a Bacterian camel. Here is a photo of a family of otters crawling over an ungainly lodge in another pond.
But these otters weren't just visiting this lodge. They were denning there, at least for that day. I saw them disappear into a hole at the top of the lodge, and then one otter pup came up to poop and went right back into its penthouse apartment.
Beavers were in that lodge at the same time, and maybe even a muskrat or two. A year before that October 2001 video, I saw a beaver try to keep a family of otters away from the lodge. At first it seemed like the otters were content just to fish in the pond and after they did and swam close to the lodge, a beaver seemed to intimidate them enough that they scooted into the grasses on shore. But then just as it got dark enough to no longer see, the otters came out from the grasses, and to their screeching delight gained the top of the lodge while the beaver vainly slapped its tail.
This blog was helpful in that it confirmed what I have observed on my beaver pond...otters and beavers occupying the same lodge. But not necessarily the same den within the (rather large) lodge.
This blog was helpful in that it confirmed what I have observed on my beaver pond...otters and beavers occupying the same lodge. But not necessarily the same den within the (rather large) lodge.
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