Fauna Series No. 3

Fauna of the National Parks — No. 3 Birds and Mammals of Mount McKinley National Park

Mammals

DESCRIPTIONS OF MAMMAL SPECIES

ALASKA PORCUPINE
Erethizon epixanthum myops [MERRIAM]

GENERAL APPEARANCE.—A large robust tree-climbing rodent. It has short legs and stout curved claws. The upper parts of the body and tail are covered with a coat of sharp black-pointed yellow quills which are barbed at the tip and are partly concealed by the long yellow over hairs that cover the body (fig. 61). The porcupine has small rounded ears that are well concealed by the hairs of the head. It is the second largest rodent in the McKinley region. Length, 29.5 inches; tail, 8 inches; hind foot 3.5 inches.

Figure 61.—The Alaska porcupine has small ears and a protecting coat of sharp quills, which are here shown erected and ready for combat.
Photograph taken May 27, 1926, Savage River. M. V. Z. No. 5092.

IDENTIFICATION.—The slow-moving waddling form of the porcupine can be readily recognized either on the ground or in the trees. At close quarters the sharp quills will dispel any possible doubt as to the animal's identity. Porcupine tracks show a canvas-like pattern where the sole of the hind feet comes in contact with dust or soft soil.

DISTRIBUTION.—Porcupines are widely distributed over North America wherever there are coniferous forests. In the McKinley region porcupines are well distributed through the spruce forests. They winter in the spruce trees but in the summer time they may be found out in willow thickets high above timber.

HABITS.—The most conspicuous evidence of the presence of porcupines is revealed by the whitened trunks of spruce trees, the bark of which is eaten extensively by these rodents during the winter. A porcupine may remain for weeks at a time in some sheltered grove of spruce trees.

On May 26, 1932, at the boundary cabin on Savage River, I found whole clusters of young spruce trees, from 2 to 6 inches in diameter, that had been killed by porcupines gnawing away all the bark near the base of each tree. Since the porcupines had selected the thickest clumps of these trees to work in, the result was a sort of natural thinning of the too thickly planted stands. In other instances isolated spruce trees showed that they had been killed by gnawing, but it is believed that such damage is nominal and natural, on the whole, in Mount McKinley National Park.

Men who drive dog teams on dangerous winter patrols do not love the porcupines, for the sled dogs are quick to attack these animals. The usual result is that the dogs in killing the porcupine get their mouths and feet full of the animal's quills and it takes hours of painful labor and endurance for both man and dogs before these quills are removed. It is accomplished with the aid of pliers, and not until the porcupine's quills have been extracted are the dogs again able to travel. Most sled dogs never learn to leave porcupines alone.

On the other hand, although a porcupine causes much annoyance by gnawing ax handles, saddle leather, boots, and other articles that have become impregnated with salt and that are therefore very appetizing to this animal, it may prove to be a veritable lifesaver to man. In the early spring of 1932 one of the members of the Cosmic Ray Expedition to Mount McKinley became lost while he was seeking aid for a sick companion. This man was unarmed, save for his alpine stock, and he told me that the meat of a porcupine, which was the only animal that he was able to capture with his alpine stock, was the principal item of food during the 3 weeks he was lost.

Wolves and certain dogs, and even red foxes, learn how to kill porcupines without getting themselves full of quills. In order to do this they get hold of the porcupine's nose first and pulling backwards drag him out into the open. When the porcupine raises up and starts to escape they run in under the front of the "porky" and flip him over on his back. The porcupine's belly is his vulnerable spot since it is not protected by sharp spines as is the back of the animal. Taking advantage of this fact the wise wolf or fox is able to kill and eat the porcupine without being bothered by the quills.

There is good evidence that porcupines were rare within the park at the time of Charles Sheldon's visit to the region in 1907-8. By 1926, porcupines had increased so that they were no longer rare and by 1932 as many as three to five were encountered in a single day.

It is probable that protection which is now being given carnivores in Mount McKinley National Park will result in their increase. This in time will act as a natural check on the porcupine population and the result will be the restoration of a normal balance.

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Last Modified: Thurs, Oct 4 2001 10:00:00 pm PDT
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