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Posts tagged “Erithizon dorsatum

Porcupines Giving Birth

porcupine IMG_3096Towards the end of April/beginning of May, Porcupines give birth to one offspring. The newborn is covered with quills, but they are soft and enclosed in a sac, which protects the mother as she gives birth to her young. The young Porcupine’s eyes are open, and it is fully alert. Its quills harden within an hour. The Porcupine starts supplementing its mother’s milk with vegetation after the first two weeks, but isn’t completely weaned for four months.

During the day the young Porcupine stays hidden in a crevice or at the base of a tree near the tree in which its mother rests. Instinct takes over immediately in the face of danger, as it tucks its head down, turns its back to the predator and vigorously flicks its tiny, two-inch tail. When night falls, the mother and young Porcupine reunite. (Photo: days-old Porcupine)

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Porcupine Artistry

1-5-16 porcupine incisor marks  634The patterns that a porcupine’s incisors leave when a porcupine has been removing bark down to the cambium can be a work of art. The way in which a porcupine makes these patterns is as intriguing as the patterns themselves. “The porcupine removes the bark in small triangular patches, each patch composed of five or six scrapes converging on an apex, like sticks in a teepee. The apex represents the position of the upper incisors, held fixed against the bark. The lower incisors scrape, moving over a fresh path as the lower jaw swivels in a narrow arc.” (Uldus Rose, The North American Porcupine) Fortunately, porcupine incisors, like those of all rodents, grow continually. Even though each incisor loses 100% of its length to wear in a year’s chewing, its length always remains the same. Juvenile porcupines leave a much less “organized” set of incisor marks (overlapping, randomly placed) than adults.

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Bountiful Apple Crop A Double-edged Sword When It Comes To Porcupines

11-5-15 apples and porcupines 011The outstanding apple crop this year bodes well for the fecundity of the white-tailed deer, mouse, black bear, raccoon, wild turkey and porcupine populations this coming year. There are other more subtle ramifications of this year’s bountiful soft mast production, however, one of which is an increase in porcupine salt-seeking behavior.

Porcupines are avid consumers of apples. Typically, the supply of apples is depleted by the end of August, when porcupines move on to beechnuts and acorns. However, this year the apple crop was so plentiful that many apple trees still bear fruit and will provide sustenance for wildlife well into the winter. High in carbohydrates, apples help porcupines gain the extra weight necessary to help them survive through the winter months.

That said, apples have a relatively low pH and are acidic, some varieties more than others. Porcupines prefer the less acidic apples, but even these contain several hundred times more organic acid than other food, such as poplar or basswood leaves, that porcupines consume in the summer. High acid intake impairs sodium resorption in mammalian kidneys, causing porcupines to lose sodium in their urine. Consequently, as a result of a high proportion of apples in their diet, porcupines seek extra sodium. While they find salt in aquatic plants, insects, animal bones and outer bark, porcupines are also drawn to plywood, car tires, outhouses, sweat-soaked tool handles and other human-related sources of sodium. This would be a good year to make sure your hammers, hoes, rakes and shovels are well out of the reach of quill pigs. (Insert shows porcupine incisor grooves in flesh of apple. Porcupines often leave cores, avoiding eating the cyanide-rich apple seeds.)

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Beaver-Porcupine Encounter

beaver with quills2  376A Porcupine’s 30,000 quills effectively defend it against two and four-legged enemies, and occasionally against its own species. Rarely, however, do we see evidence of this mode of defense outside of our family dogs, most of whom are challenged when it comes to learning from the experience. From the size of the quills in this Beaver, one can assume it came in contact with either the Porcupine’s upper back or neck, where the quills are longest (up to 4”). How and where this encounter took place is a mystery. Porcupines can and do swim – their quills are filled with a spongy material which may enhance their buoyancy. So it’s within the realm of possibility that these two rodents met in the water, but that seems unlikely. While some quill injuries result in death, a surprising number of victims recover. One researcher observed that the quills he saw in a raccoon’s muzzle were worn down to a stubble within a week. Due to tiny barbs on the end of the quill that contacts another animal, it can work itself into an animal’s body, but those in this Beaver will hopefully come to rest against its jawbones. As long as the Beaver can eat, its chances of survival are good. It is unlikely to get an infection from the quills, as they’re coated with fatty acids that inhibit the growth of bacteria (in case the Porcupine stabs itself?)

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Porcupettes Being Born

5-20-14 porcupine IMG_3143This newborn porcupine is about a foot long from the tip of its nose to the tip of its tail, weighs roughly a pound and has quills about one-inch long. It will nurse from its mother for the next two months, but within two weeks will be feeding on vegetation as well. Because its offspring is precocial (capable of traveling and feeding on its own soon after birth), the porcupine’s mother provides care for her one offspring only for a week or two before leaving it to fend for itself.

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