Once upon a time . . . no wait. This isn’t a fairy tale.
Rather, it’s about changes in the landscape that one might observe, such as a brook suddenly overspilling its banks as was the case in this location upon a December visit. We’d had rain, but that much?
It wasn’t long before a friend and I spotted the reason for the high water. Some new residents had moved into the area and built a lodge of sticks. Unlike the story of the three little pigs, one of whom built a house of sticks that the big bad wolf came in and blew down, the makers of this structure took special care to make it solid and strong and weatherproof. Yes, a beaver or two or six had taken up residence with the intention of spending the winter. Beaver families usually consist of a monogamous couple, plus their two-year-old (almost adult) kids, and yearlings. Mating occurs in the water during the winter and kits are born inside the lodge in the spring.
In order to move into the lodge, a dam needed to be constructed as well. If you look closely, you’ll see that above it there was a bit of an infinity pool with the ice at level with the dam, while below it some water flowed at a much lower level. Though we couldn’t walk along the ice to measure the length of the dam, it was quite long. and made of sticks and leaves and mud. Typically, the family works on this project by creating a ridge of mud and probably the herbaceous plants of the meadow, and then they use the mud and sticks to stabilize it. Maintenance is a constant as water or other critters or humans have a way of breaching the dam.
We, too, build dams to serve similar purposes, such as this one originally constructed to operate a saw mill. Hmmm.
Getting back to the lodge: it also needs nightly work as long as conditions allow and this has been a winter of despair for those of us who love cold temperatures and snow and even ice if it’s in the right place, like on a pond or lake and not in the driveway.
Take a look at how the beaver is holding the small twig.
A beaver’s dental formula is this: 2 incisors on top, 2 incisors on bottom, 0 canines on top, 0 canines on bottom, 2 premolars on top, 2 premolars on bottom (that look like molars), 6 molars on top and 6 molars on bottom, for a total of 20 teeth. Recently, I was able to sketch the upper part of the skull of an older family member, who’d lost some of its molars.
These large, semi-aquatic rodents are gnawers like their relatives. To that end, their incisors are highly specialized for chewing through really, really tough things and they grow continually throughout the critter’s life.
And like all rodents, the front surface of their incisors is coated in enamel reinforced with iron (hence the orange color), which makes it resistant to wear and tear from gnawing. When the chisel-like teeth chew and fell trees, the much softer white dentine layer (the section behind the enamel) is ground down quicker than the enamel, thus creating a sharp chisel surface.
But to me the coolest aspect is that their lips close behind the incisors, thus permitting them to gnaw and carry sticks underwater without choking.
And bingo, you can see the stick being carried in that gap between the incisors and molars. Food sticks become lodge or dam sticks once their nutritional value has been consumed: a true plan of repurposing.
As it turns out, that wasn’t the only beaver family at work in town. This next family, however, chose to park their tree in a spot the fire department lay claim to for filling a water tank. But . . . reading is not on a beaver’s talent list.
In this other place, so many trees have been felled, but not all have fallen as intended, getting hung up on other trees instead. Not wanting to anthropomorphize, but I have to wonder what expletives flash through a beaver’s brain when trees don’t hit the ground as planned.
As strict herbivores, a beaver’s diet varies with changes in the season. During spring and summer, they are drawn to waterlilies, algae, grasses, sedges, herbs, ferns, shrub leaves and shoots. By late summer, however, tree cutting begins as they gradually change their dietary habits from herbaceous to woody materials. Twigs, roots, bark and especially inner bark become the source of nutrition. Aspen, birch, alder, and willow are favored species, but beavers will cut almost anything including conifers.
Imagine this. A beaver cocks its head to the side as it gnaws, thus the consistent angle of the half inch groove as the upper and lower incisors come together.
Likewise, porcupines gnaw, but their incisors are much narrower and the pattern more random.
So, the question remains. Where were the parking lot beavers living? In the past, a family has inhabited the northern most reaches of this pond, but in this case, they had built a lodge on a point not far from the southern end.
The top of the lodge is the only section not covered with mud, for it serves as a “smoke stack” of sorts, a place for beaver breath to escape. Visit a lodge on a cold winter day and you might observe the vapors rising.
And then it was on to another locale, where beavers have inhabited the same lodge for a number of years. When beavers choose to live in a pond or lake or sometimes even a river, there’s no need to build a dam for the water is usually deep enough for their underwater movement.
I often tell people that beaver prints are a rare find because they are either wiped over by the tail or by trees being hauled to the water. Once in a while, however, I’m proven wrong and the sleety snow on a recent day awarded just the right conditions for the webbed feet to be observed.
Tree work and broken ice added to the story of the critters’ journey to and fro the pond. While quite adept at time spent in the water, they are rather clumsy on land and most of their work is within a hundred feet of the edge.
Winter food is cached close by the lodge entrance so that they can swim under the ice to retrieve a stick. A beaver’s ears and nose have a valve that closes when it is submerged and they can stay underwater for up to fifteen minutes. Back at the lodge, there is a raised chamber surrounded by a moat that leads to the entrance tunnel. It’s upon the raised area that they dine, and groom, and even give birth.
At this particular pond, My Guy and I noted two lodges connected by an open channel between. Given the number of tail slaps that announced our presence near both lodges, we thought perhaps both were active and inhabited by the same family.
And then, and then . . . finally, we spotted a beaver that spotted us. We kept expecting it to slap the water with its tail in a manner of warning so other family members would seek deeper water or cover. Instead, it swam past us.
The thing is that a rodent relative, namely the muskrat, exhibits many similarities, but also differences, including a skinny, snake-like tail.
The beaver’s tail is a source of wonder. While its furry body consists of long, shiny guard hairs covering dense and softer hair that traps air and helps protect the critter from the cold, the tail is broad and flat and scaly. It’s used for a variety of reasons including stability when standing upright on land (think tripod), as a rudder for propulsion in water, as fat storage and thermal regulation, and how we are most familiar, as a warning device.
A beaver’s tale indeed.
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