This is the time of year when the industriousness of beavers can determine whether or not they survive through the winter. There are three major tasks for a beaver colony to tend to in the fall: refurbishing their lodge; strengthening and repairing their dam; and cutting and storing their winter food supply. They tend to perform these tasks in this sequence, tackling the lodge first. If the water level is high, the beavers will raise the floor of the lodge and the roof of the sleeping chamber. Every fall they add new material to the exterior of the lodge to strengthen the entire structure – typically sticks intertwined that create walls two feet thick or more. At this point the beavers coat the lodge with mud that they dredge up from around the base of the lodge (which greatly increases the depth of the water near the lodge). The apex of the lodge is not coated, allowing fresh air to filter down into the sleeping chamber. Once cold weather arrives, the mud hardens to the consistency of concrete, making the lodge is impenetrable to predators that can approach the lodge once the pond freezes. (In photo, note the fresh eastern hemlock branches and mud that have recently been added to the lodge.)
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Recent discovery of black bear tracks and scat confirm that hibernation has come to an end, at least for some bears. During the winter black bears lose an average of 23% of their body weight. Because there is a scarcity of food when they emerge from their dens, black bears continue to subsist off the fat that they put on last fall, and thus continue to lose weight. The diet of black bears is high in carbohydrates and low in proteins and fats. When hibernation is over, they head for any available succulents and protein-rich food, including bird feeders.
Do you know a 3 – 8 year old who loves animals and would enjoy getting close-up views of the antics of a red fox kit during the first summer of his life? My second children’s book, Ferdinand Fox’s First Summer, has just been published by Sylvan Dell in both hardback and paperback. I have been lucky enough to have had the opportunity to observe and photograph young red foxes as they interact with each other and with their parents. This book consists of a selection of these photographs, accompanied by text and an educational component at the end of the book. Look for Ferdinand Fox’s First Summer in your local bookstore. If they don’t carry it, you would be doing me a huge favor by asking them to. Thank you so much. My next children’s book is on Beavers and will be coming out in the spring of 2014. (I am still looking for a publisher for Naturally Curious Kids!)
A study of coyote prey (through stomach contents) in the Adirondack Mountains of New York revealed that beavers were second only to white-tailed deer. This photograph shows that, possibly for the last time this winter, a coyote recently took advantage of a still-frozen-but-fast-thawing pond by walking across it in an attempt to reach an active beaver lodge. Once there the coyote attempted to dig into it in order to reach the inhabitants. A hard, two-to three-foot-thick wall of frozen mud, logs and sticks kept the beavers well protected, as it was designed to.
I can’t let another minute pass without bringing a website to my readers’ attention, as activity has really picked up recently. The live-cam installed inside a bear den in Ely, Minnesota at the North American Bear Center captures the sounds and movements of a mother bear and her two six-week old cubs 24 hours a day. Everything from the mother’s birth to the fall and rescue of a cub has been recorded. Enjoy part of your snowy (or not) Sunday by taking a look at this ursine family. You may have to have considerable patience before seeing a cub, but it will be worth it, and you’ll hear them night and day! It will be obvious to you that female black bears with newborn cubs do not have the luxury to go into as deep a hibernation as their mates, who are blissfully asleep in their own den. Go to http://www.bear.org/website/live-cameras/live-cameras/lilys-den-cam.html and click on “live stream” in the upper right hand corner of the picture of the bear to view live coverage. You can also see tapes of past activity, both here and on “Lily the Black Bear’s” Facebook page.
A recent exploration of some rocky ledges, a favorite winter denning site of porcupines, revealed a virtual maze of trails leading to roughly a dozen crevices where porcupines sought shelter. A look inside these crevices confirmed that porcupines leave something to be desired when it comes to keeping house. Unlike many other animals that keep their dens pristine (e.g. beavers only defecate in water, never in their lodge), porcupines don’t feel the necessity to roust themselves when nature calls. As a result, the floor of their den consists of years of accumulated scat (and urine). In some cases, the pile of scat in these ledge dens was so high that it made you wonder how a porcupine could even fit into the crevice, and indeed, in some cases, porcupines do have to dig their way out of their den. When it became aware of my presence, the pictured porcupine assumed its characteristic defense posture, exposing its quill-filled back and upper tail surface to the intruder. It needn’t have worried, as the opening was barely wide enough to get the camera into, much less the photographer!
If you take a walk along a small wooded stream that has many fallen trees along its banks, you can expect to find mink tracks somewhere along it. These wetland-loving weasels dig their dens in river banks, often under tree roots, and judging from their tracks, visit them frequently. It is not unusual for one mink to have several dens which it uses as resting spots along a stream. Mink spend a lot of time in the water hunting for fish, aquatic insects and crayfish. Mink are good swimmers and can dive as deep as 16 feet. Tracks will run along the frozen sections of a stream, and then disappear into the water, only to reappear on the ice further downstream when the mink decides to travel on solid ground again.
Roughly a month ago woodchucks were at the peak of their mating season. New England’s largest member of the Squirrel family is about to give birth to two to six young chucks. In preparation for this event, dead grasses are gathered and carried by mouth to the underground nest chamber, which is about 15 inches in diameter. Woodchucks are tidy rodents — the female covers her young’s waste with new bedding placed directly over the old, and when the nest becomes too bulky or unsanitary, the matted material is removed and fresh bedding is added.
For the first month or so of their lives, red fox kits remain in their den. They are born with a coat of dark gray fur, which is replaced when they are about a month old and starting to emerge from their den. Their second coat is sandy-colored and blends in well with the soil surrounding the den entrance, where the kits spend most of their time. By late June they will have acquired the red coat we associate with adult red foxes. Meanwhile, if you know the whereabouts of an active den, there is no better or more fun time of year to watch the antics of young kits than right now – they entertain themselves while their parents are out hunting by pouncing on each other, having mock fights, playing tag and chewing on all kinds of things from sticks to feathers – all of which is interspersed with frequent naps.
A sure sign of spring is the emergence of woodchucks, the largest members of the Squirrel family in New England, after a long winter’s sleep. Their arousal is easily noted, for when the males wake up, they do some excavating of their tunnel, scattering dirt all around it which is easily spotted on the snow (if there is still any snow left). Equally obvious is the muddy trail they leave when in search of a female. Mating takes place in March and April, and the resulting litters of 2 to 6 young are born a month later.