Part 8

Sometimes twigs bearing a cluster of cones are nipped off. In two or three sizeable caches all the cones were in clusters still attached to twigs. Perhaps this rather efficient method of handling cones is at times accentuated by certain individuals.

In September I have seen many caches scattered about on the forest floor as though piled hurriedly as a temporary expedient. One heap measured 5 feet long, 3 feet wide and about 7 inches deep. Possibly these heaps were later stored more carefully in secluded spots with the tips of the cones pointed downward. After the cones are stored, the squirrels continue to give them solicitous care. One spring when melting snow exposed a cache of cones, they were re-cached in various places, but each cone was first bitten into, and if spoiled was discarded. About the same time another cache of cones in a burrow was also removed and stored elsewhere.

Another food item that is stored in quantity is the mushroom. Many are placed on spruce branches where, if they do get wet, they will soon dry out and remain edible, and I once found great quantities stored in a cabin.

Aside from the cached foods, the red squirrels feed extensively, at least through the winter and spring, on the buds of spruce twigs. Often you may find many twigs on the ground with the tiny buds neatly removed. In Wyoming, I have found squirrels in summer living for days on the larvae in cottonwood galls, and I suspect such food may be eaten in Alaska too, where galls are found.

Each squirrel commonly has two or more nests built of grasses, shredded bark, ptarmigan feathers, and hair of rabbits, moose or whatever is available. The squirrel piles this material on a branch until it is 2 or 3 feet high. One squirrel that I watched building a nest pushed himself into the middle of the heap. Soon the whole nest shook vigorously at intervals. Apparently he was forming a chamber.

The chatter of red squirrels, their piles of middens and their busy harvesting activities, add cheer and life to the northern woods.

Northern Flying Squirrel Glaucomys sabrinus yukonensis

When the gesticulating red squirrel has finished his daylight bustling and retires to his nest, the flying squirrel comes forth to take over the night, but in a gentle and quiet manner. Like the night-flying owl, its coat is soft and its flight silent.

The furred “wing” membranes on each side of the body are attached to the full length of the fore and hind legs and are supported and extended in part by a cartilaginous process growing out from the wrist. Thus when the legs are extended laterally, the squirrel becomes a glider with the most delicate and reliable controls. His sailing carries him from the top of one tree to the base of another where he checks his speed by an upward swing and alights with a soft thud. Sharp claws and squirrel agility give him the climbing ability to get quickly up a tree. Where trees are widely spaced as they are in some stands of large cottonwoods, he may in winter make a five-point landing in the snow, his broad thickly-furred tail serving as rudder and gliding surface, and to a less extent as a landing ski. I have seen tracks showing a touch and a raise before the final landing with legs drawn under; then follow long jumps over the snow to the nearest tree. The nest is usually built in a tree cavity.

Perhaps the height of night esthetics is lying in a sleeping bag under the open sky, the stars and moon lighting up the spaces between the trees, and watching a family of flying squirrels gliding overhead in their night play, their shadowy forms silhouetted against the moonlit sky.

Porcupine Erethizon dorsatum myops

The porcupine has been accused of being slow-witted, but we must admit that he has not done badly for he is able to lead an unhurried life in the country. His quill protection has, no doubt, decreased his need for mental activity, and his eyesight does seem deficient. But his hearing is quite keen, and judging by his nose activity it appears that his sense of smell is on the acute side. His mental and physical attributes are all based on the quill.

The upper surface of the porcupine, except for the vulnerable face, is covered with several hundred ivory colored quills, touched with black or brown, and reaching a length up to at least 2½ inches. They are needle-sharp and just back from the tip are numerous minute barbs. When the quill enters the flesh of an enemy, any muscular movement causes the quill to move forward until it emerges on the opposite side or becomes lodged against the bone or under the hide.

When the porcupine senses danger he raises the quills on his back and has his muscular spine-studded tail in readiness to flip upward. He tries to keep his rear toward the enemy and to push his head into protective brush. The quills are loosely attached to the skin so pull out readily when they stick into anything. The underside of the body, in addition to the face, lacks quills but because of the short legs, the belly region is close to the ground and not vulnerable unless the porcupine is flipped over on his back. I knew a sled dog that sometimes killed porcupines by weaving and maneuvering until he had an opportunity to grasp the vulnerable nose and thus avoid the quills. Wolves, coyotes and wolverines feed on porcupines; possibly they use a similar technique in overcoming the quill armor.

In winter the porcupine feeds extensively on the inner bark and the needles of conifers. The patches where the bark has been removed are a common sight in porcupine woods. The spruces, in the last stand of timber on the east side of the Toklat River along the road, were nearly all killed by girdling, many of them back in the 1920’s when the porcupine population was extremely high. This scraggly woods is a favorite nesting area for pigeon hawks, sparrow hawks, magpies, and shrikes so that porcupine activity that seemed generally harmful has been highly beneficial to these species. Many porcupines spend the winter in a willow patch beyond the spruce and subsist on willow. For shelter in winter a windfall, hollow tree, or an old fox or wolf den may be used. Several may take residence under a cabin.

In spring I have watched porcupines climbing clumsily in tall willow brush feeding on the swollen buds. Swaying on a limb he reaches for a slender branch, pulls it to him and passes the length of it past his nose to discover the buds which he nips off. If the branch is obstreperous and cannot readily be handled in this manner, he severs it with his rodent incisors and then removes the buds as his paws manipulate the twig past his jaws. The new shoots of fireweed and other herbs are avidly sought in early summer. Willow leaves are included in the varied summer diet.

The breeding season is in the fall and the young are born about 7 months later. The usual single young one weighs about a pound, almost as much as a new born grizzly. The eyes are open, the short spines are evident, and protective reactions are soon functioning.

Their voice development is quite obvious when one or more porcupines resides under a cabin. The night moanings, squeaks of irritability, cluckings, and caressing sounds are enough to keep even the exhausted hiker awake.

Beaver Castor canadensis

Beavers may be found at Horseshoe Lake, Riley Creek, various ponds near the Nenana River, and in ponds and creeks along the road in the Wonder Lake region. They are out chiefly at night, but many families emerge for pond activity by 2 or 3 o’clock in the afternoon.

Beavers are large rodents, scaling 60 pounds or more. Their weight does not make them good hikers but it is no handicap in water where they paddle their way about as though they were skiffs. And when they sit up to gnaw down an aspen or cottonwood, a favorite pastime, a good solid fulcrum might be a comfortable advantage. The broad, flat, scaly tail serves as a prop when sitting erect, as a rudder when swimming, and for sounding an alarm (by slapping water) when an enemy is discovered.

The front feet are equipped with five strong toes which serve well as hands for holding twigs as the animal feeds on bark. The claws function well in all digging operations, and the arms suffice for holding gobs of mud against the chest as he pushes the load onto the dam or house. Occasionally, he carries mud in his arms as he walks up the house roof on hind legs.

The hind feet are large and webbed for swimming. Even the nails on the toes are flattened in keeping with the swimming needs. The nail of the second hind claw is double and the nail of the first toe fits down on a hard pad and is movable like a duck’s bill. These specialized claws are used for combing the fur and possibly for removing some of the large beetles that live in the fur. The prominent incisors, used for gnawing, grow continuously, as they do in all rodents, in order to compensate for wear. This is an especially fortunate adaptation for the beaver, who does so much gnawing. Otherwise his teeth would soon be worn to the gums. If an incisor for any reason is thrown out of line, so it has no surface to bite against and wear, it will become excessively elongated as it grows in a curve.

A flourishing beaver colony apparently consists of the parents, the young of the year, and the previous year’s offspring. It is for this reason that we often discover three sizes of beavers in a pond. Much of beaver activity involves cooperative projects where there is latitude for any amount of individual initiative. The dam or dams must be built, or raised, or kept in repair. The house, located either out in the pond, or partially or wholly on the shore, may require additional sticks, and toward autumn is plastered on the outside with wet mud as a sort of annual renovation. This “stucco” winterizes the lodge. Occasionally, it is decided that a new house is needed and that gives young and old plenty to do. Some beavers along Riley Creek live in bank burrows and build no dams or houses.

The most effective dam that has come to my attention was built at the outlet of Wonder Lake in 1960; it raised the water level of the lake over 2 feet. For many days the outlet stream was dry. The water held back in the lake amounted to well over 100 million cubic feet or over 7 billion pounds of water.

The water depth beside the lodge must be deepened if too shallow, so that the underwater entrance to the lodge is deep enough to keep from freezing over, and imprisoning the occupants. Also a certain depth of water is needed beside the lodge in which to store the brush pile that is the winter food supply. Another activity practised extensively by some colonies is the building of canals, some of which may have great length. The mud from the digging is deposited along the canal forming a raised border. These waterways are useful for general travel to food areas and for transporting branches and poles.

The favorite foods of the beaver include willow, aspen, cottonwood, and alder. Willow brush re-sprouts readily and grows rapidly, therefore maintains itself better than some of the other foods. Also it flourishes in the wet habitat created by the beaver ponds.

Where beavers create ponds with their dams, they produce a habitat for fish, ducks, muskrats, shore birds, moose and many other forms of water and shore life. In Wyoming, I have observed the dead trees, killed by flooding, used by herons for nesting, and one of the heron nests was later used by a pair of geese.