Popular Science Monthly/Volume 25/May 1884/The Beaver and his Works
|THE BEAVER AND HIS WORKS.
By Dr. G. ARCHIE STOCKWELL.
THANKS to the decrease of castor in value, owing to the substitutes which have been found in the skins of seal, nutria—the improved preparation of other peltry of little value, such as the hare and rabbit—and more than all in the use of silk in the manufacture of hats, a little breathing-time has been allowed the beaver, which a few years since bade fair to speedily become extinct.
Formerly inhabiting every part of North America possessed of forest-growth, at present it is found only in the wilder and least accessible regions of the continent. At the time the reindeer, musk-ox, mammoth, and rhinoceros roamed the temperate zone, beaver were abundant, and filled the country on every hand, from the Mexican Gulf to the Barren Grounds, with their works—wondrous monuments of patience and industry. Perhaps their fur helped to clothe the ignorant savage that eked out a precarious existence by means of game killed with flint-tipped arrows and javelins, and dismembered and divided by hatchets and knives of stone. Doubtless the broad tails were then, as now, esteemed delicate tidbits. And the wondrous instinct displayed may possibly have taught the primeval dweller the rudiments of architecture now exemplified in beautiful structures of wood and stone; for to this day we find some tribes, low in the scale of humanity and civilization, such as the Fischer Lapps and natives of Terra del Fuego, living in huts that, save in point of size, are exact counterparts of the dwellings of the beaver.
Of all quadrupeds, the beaver is one of the most peculiar and interesting. He is the only one that possesses membranes between the toes of the hind-feet, at the same time none on the fore ones—in fact, resembling a terrestrial mammal in front, and an aquatic one behind. When full grown, he exhibits a thick, heavy body over two feet in length, and from thirty to fifty pounds' weight, terminating in a full, compact, cat-like head, with heavy jaws provided with wondrous muscular development. The tail is oval, resembling closely the blade of a paddle, twelve or fourteen inches in length, and four or five in breadth, flattened both above and below, and covered with a thick dusky skin that at first glance appears to be protected by scales. The old writers were accustomed to tell us that this peculiar appendage was used as a trowel for plastering his dwelling or repairing his dam, as a maul for driving stakes, and as a vehicle for transporting loads. But modern science has proved the fallacy of such statements, and we now know that it serves but as a prop or fifth leg when sitting at work, or as scull and rudder while navigating the waters.
Generally, beaver are nocturnal in habits, mild and tranquil in position, but not inclined to be social except among immediate relatives. They are also the perfection of neatness and cleanliness, possessed of very acute sight, hearing, and smell; and, when domesticated, very interesting and even affectionate pets.
Fig. 1.—The Beaver.
During the summer they are more inclined to solitary habits, except where a new settlement demands their energies; but in autumn they appear in families, which remain unbroken until the following spring. About the middle of August the busy season begins, and each and every one, both great and small, assist in repairing the dam and dwellings, which for some months have been allowed to fall into neglect and unrepair. Trees are felled and cut into suitable lengths, and, along with stones and clods, dragged laboriously to the scene of labor until all is made again secure against ice and cold. Other trees, such as larch, willow, birch, and aspens, are cut up into billets and twigs, and stored for the food their bark affords, against possible want. Their perseverance in this work, the labor expended, and the strength of teeth and jaws, may be fairly estimated by the stumps that remain, as they are found of all diameters, from the smallest brush-wood to growths a foot or more in diameter. I have seen stumps that measured but a fraction less than sixteen inches.
It is with the front or incisor teeth that the cutting is done, and they are eminently adapted to the work, being long, square-crowned, and with edges beveled in the same way as is the carpenter's chisel known as a "firmer"; and the rapidity with which the work is performed may well astonish one who is fortunate enough to witness their proceedings.
Commencing at a height of twelve or fourteen inches from the ground, a distance easily reached while sitting upon the tail and haunches, the tree is gouged around in a complete circle, equally on all sides, but gradually growing deeper and deeper with each circuit, forming, as it were, two cones whose points meet at a common center. When the space chipped out proves too narrow to admit the head, the teeth are applied above and below, as the woodman plies his axe, until the desired result is obtained. Steadily and faithfully he labors, rarely resting, and then but to take a refreshing bath in the nearest pool. At the last he frequently pauses, and, erecting himself upon his hind-legs, feels the trunk with his paws, as if to determine which way it shall fall, or whether it shows any signs of yielding; finally, when perhaps but an inch or two of the heart remain uncut, he gnaws vigorously upon the side toward which he desires it to fall, and, as the warning crack is heard, whips himself with great celerity and adroitness to the opposite side to avoid being crushed in its descent. Next the trunk is divided into lengths, and dragged by aid of teeth, paws, and chin to the water, where it is floated to the dam or storehouse. When large trees are chosen, they almost invariably stand upon the margin of the water, into which they are made to fall; but small growths are frequently sought at considerable distances, and regular paths or "runways" are beaten in the tall grass and ferns where such have been transported. The number of trees felled by one small colony is surprising, and the regularity of the stumps left might lead one unacquainted with the cause to believe them the result of human industry.
When the beaver selects a home on the bank of lake, pond, or stream whose waters are both deep and abundant, dams are rendered unnecessary, and even houses are not always constructed, but instead dwellings are hollowed out from the banks. But on shallow, narrow waters, dams are indispensable in order to secure sufficient depth to allow of concealment and free movement beneath the surface, as well as to prevent obstruction by ice: the entrance to the dwelling or storehouse is always beneath the water, which acts not only as a doorway, but as a safeguard from predatory enemies.
In the building of a dam considerable engineering qualities are developed. It is seldom seen as a mere straight embankment, but goes winding across the stream in graceful curves, bending hither and thither to present its convexity toward the swifter flowing current or deeper waters, taking advantage at the same time of all natural inequalities, now a rock, here an islet, and there a hillock. Trunks of trees are carefully intermingled with clods of earth, stones, and twigs, and every crevice is carefully stopped with mud or clay for greater security; and, when all is finished, the whole presents a structure of almost incredible solidity and compactness, frequently increased by the roots of willow and larch which spring up with all the regularity of a hedge. In the neighborhood of Washington Mine, Lake Superior, may be seen a dam with a total length of fifteen hundred and thirty feet, but the two ends, more than two thirds of the whole, are but natural embankments artfully rendered subservient to the purpose of the beaver by filling in between.
Fig. 2.—Beaver Dam.
It is these dams that produce those fine tracts of wild grass known as beaver-meadows, upon which cattle and deer so love to feed, and which so frequently furnish the pioneer with the means of subsistence for his stock until he can prepare meadows of his own. Wherever a brook trickled through a wooded valley, there the beaver made his home. Large areas became inundated, the drowned trees fell and decayed, and the freshets brought down new soil from the surrounding hills and ridges. At length the pond filled up and forced the beaver to migrate; the dam unrepaired gradually became shaky and the waters drained off, exposing a rich alluvial soil upon which sprang up waving fields of wild grass. In due time a second growth of timber appeared, and what was once a pond and valley became only a forest bordered by low ridges. In the suburbs of the city of Port Huron, Michigan, may be traced the remains of such a dam, of unknown age and stupendous length. Serpentine in windings, its face may be followed for more than twelve hundred yards ere it becomes indistinct; and doubtless it was originally much longer, as its eastern end has been encroached upon by streets and dwellings. What its height may originally have been can be only a matter of conjecture, as time and the elements have combined to reduce it nearly to a level with the surrounding soil; and its top has given birth and nourishment to mighty trees, long since yielded up to the rapacity of the lumberman, many of whose stumps, half decayed, yet exhibit more than four hundred rings of annular growth. This, too, is but one of a series of five dams upon the same stream grouped in a space of little more than two miles. The Indians have no knowledge or tradition regarding it, though they frequently discovered "stone-wood" (fossil-wood) bearing the marks of beaver-teeth, at the points where the streams forced the barrier.
Of more recent beaver-dams, the writer has examined a few that may be held remarkable. Besides the one near Washington Mine, before mentioned, one on the Ely Branch of the Ish-ko-naw-ba (on the maps misspelled Escanaba), in the Upper Peninsula of Michigan, giving origin to a pond, with an area of nearly one hundred acres, known as "Grass Lake"; its length is two hundred and sixty feet. A third in the same peninsula, four hundred and eighty feet long, is on Carp River. But the largest is to be found on Sable River, in New Brunswick, and floods upward of one thousand acres of land at an average depth of two feet. Mr. Thompson, whose writings are deemed most authentic, speaking of a dam visited by him in New Brunswick, in 1794, says:
"My guide informed me we should have to pass over a long beaver-dam. I naturally expected to lead our horses carefully over, but on coming to it found a strip of apparently old and solid ground, covered with short grass, and wide enough for two horses to easily walk abreast. The lower side showed a descent of seven feet, and steep, with a rill of water beneath. The side of the dam next the pond was a gentle slope, and the pond itself a sheet of water a mile and a half square, surrounded by low, grassy banks. The trees about were mostly poplars and aspens, with numerous stumps, whose trunks had been cut down and carried away by the beavers." In two places in this pond were observed clusters of houses "like miniature villages."
One is usually disappointed with the first view of a beaver's house. Instead of the symmetrical, round, plastered dome we are led to expect from most popular accounts, there is seen instead an irregular pile of sticks, mingled with rushes, grass, and stones, broad at the base as compared with the height, and of the same general order of architecture as the dam. Apparently devoid of system, it resembles nothing so much as a gigantic crow's nest turned upside down by the border of a pond or stream. And yet, though they are not plastered smoothly, and the interior exhibits but rough walls merely evened by cutting close the twigs that project through in building (the whole affair apparently conceived and put together in a helter-skelter fashion), they are very compact, exhibiting both solidity and firmness, and are well adapted to warmth and protection. Each dwelling consists of but one apartment, and this opens by a short incline beneath the surface of the water into a channel dredged to sufficient depth to avoid being blocked by ice in winter. It is easy to determine whether a dwelling is in present occupation by the appearance of the trails over which the beaver drags his supplies from the wood; by the freshly-peeled sticks the bark of which has served for food, and which are invariably heaped up upon the house itself; and in winter by the melting snow on the roof caused by the exhalations from the occupants.
One dwelling harbors from four to twelve individuals, rarely more, though eighteen or twenty have been noted, all of the same family, but of two generations, representing litters of kittens of two successive years. The young make their appearance usually in May, and are from four to eight in number, five being the average. Queer-looking little fellows they are too, with their heavy heads, big cutting teeth, flat tails, and fine, mouse-like fur, not yet disfigured by the long, coarse hair so noticeable with adults. When taken at an early age they are easily domesticated, and are so esteemed as pets in the far West and fur countries that almost every trading-post or camp can exhibit three or four. It is no uncommon occurrence to see one running about an Indian lodge, submitting patiently to the wiles and caprices of the little savages, or joining in their sports, and frequently receiving with the papoose the nourishment from the maternal breast. The cry of the "kitten," too, is so exactly like that of an unweaned child that one is readily mistaken for the other by even the initiated. On one occasion I visited a wigwam at Little Traverse, Michigan, for the purpose of viewing a "real, live, baby beaver." "He cry all same as papoose," remarked the squaw, as she brought the little fellow forward, at the same time giving him an unmerciful pinch that caused him to set up a doleful little wail that, had I not been forewarned, I should certainly have believed to proceed from a minute, black-eyed specimen of an aboriginal infant that, swathed in cloth, beads, and bark, and bound fast, mummy-like, to a board, stood leaned up against the wall. By-the-way, do Indian babies ever cry or laugh? I suppose they do, occasionally, though I do not remember ever hearing one. I think it is Mr. Lewis Morgan, in his excellent work on "The American Beaver," that tells of a trapper on the upper Yellowstone who, while making his rounds, heard, as he supposed, the wail of an infant. Fearing the vicinity of hostiles, he approached with great caution, only to find that the cry proceeded from two beaver kittens sitting upon a low bank by the stream, and mourning for the nourishment only a mother could give; while she, poor thing, was fast in the merciless jaws of his trap.
When the youngsters have completed their second year, they are unceremoniously turned adrift by the parents to shift for themselves. If possible, they locate farther up the stream, but, if this is impracticable, select the nearest situation possessing the necessary requirements. It sometimes happens that there are so many dams on the same stream that the back-water from one sets into the next, and that in turn into the one preceding, and so on through the series. It is usually the case that a large colony in any one locality is derived from a single pair of beavers.
Occasionally solitary or "lone beavers" are met with by trappers; animals that do not erect dams or houses, but reside in holes and clefts in the banks which they have excavated, or which are the product of nature or of some of the burrowing tribes, as the otter. The cause of their abandoning the society of their kind is unknown. It may be an excess of that melancholic temperament that is assigned to the species; possibly, the hermit is the sole representative of an extirpated colony; perhaps a bachelor unfortunate in being unable to procure a helpmate; the Indian tribes represent them as pariahs or outcasts, doomed by their kind to solitude on account of shiftlessness or idleness. Certain it is, they are seldom in good condition, and their very mode of living precludes industry.
The trapping of beaver may be considered as an art in itself, as it demands no small expenditure of patience and perseverance to acquire the experience necessary to make it a lucrative calling. Once on the ground selected as the scene of his labors, the trapper follows the creeks and streams, keeping a sharp lookout for "sign." Every prostrate tree is examined to see if it be the work of the beaver; tracks are sought for in the mud and sand; and trails through grass and ferns submitted to careful inspection. The lay of the land having been thoroughly studied, and the presence, movements, haunts, and habits of the animal determined, traps are set at frequent intervals in those localities most likely to produce satisfactory results, and duly baited with "medicine." They are placed both on land and in the water; in the runways, at the landing-places, about the dwellings, and before the storehouses, and are visited daily. On land the old-fashioned "dead-fall" has the preference, as it breaks the animal's back without damaging the skin, while the steel trap in such locality only too frequently results in the escape of the quarry, though at the expense of some one of its members; for the beaver does not hesitate to exercise its sharp teeth in the performance of amputation in order to secure safety. That judgment is demanded in preparing a dead-fall is evident from the fact that it must be adjusted with such nicety that no animal larger than a beaver can pass beneath it, and yet be incapable of being disengaged by anything smaller, such as a mink or musk-rat; the drop-log, too, must be of dried peeled wood, lest it be pulled down by the very animals it is intended to capture, and carried off to their storehouse. The "medicine" used as bait, sometimes denominated "bark-stone," is the product of a gland of the beaver, of peculiar, disagreeable odor and bitter taste, known in medicine as castoreum, which has earned for itself considerable reputation as an antispasmodic and nervine, though of late years it has largely been superseded by remedies of more agreeable flavor; for some reason it proves very attractive to beaver, alluring alike both old and young of both sexes. A bit of peeled apple, or the bulb of the water-lily, is also used as "medicine," but is not considered as "taking."
Where the water is constantly ebbing and flowing, steel traps are frequently of little value, though under ordinary circumstances to be preferred. A trap requires some six inches of water over it, with still deeper water beyond, for the moment the beaver feels its jaws, which invariably grasp a foot or toe, he turns a somersault into the deeper pool in the vain hope to shake it off, and there drowns. But, should the water be deeper, he swims over the trap unharmed; if lower, he releases himself by amputation; and a beaver who once tastes the perils of a trap is not only ever careful of assuming a second risk of the kind, but seems to possess the faculty of warning his companions. When a trap is set before the dwelling, the channel leading to the door is found by sounding, and it is placed therein, guarded on each side by two stakes that preclude passing except by the dangerous path. It is placed a little nearer one stake, in order that any attempt to cut it will insure a fore-foot touching the pan; if the other stake is attacked, then a hind-foot is caught.
Sometimes, especially in winter, stakes are driven through the ice so as effectually to block up the entrance to the house, whose roof is then broken open, and the inmates dispatched. Again, the dam is cut in numerous places and traps are set in the openings, that the beaver may be caught while attempting to repair the breaches. But neither of these processes is in vogue with the true trapper, unless the colony be a very small one, as the animals are likely to have burrows in the banks that serve as store-houses into which they retire at the first alarm; and the loss of two or three of their number while repairing the dam will render the survivors extremely cautious and wary, perhaps cause them to migrate in a body.
The quickness with which a colony discovers a wholesale attempt against their peace is astonishing; yet if their numbers are undisturbed, or diminished but gradually, even the presence of civilization will not drive them from their haunts. To-day beaver are returning to streams in Michigan, long ago abandoned by their race, simply because they find themselves unmolested, the demand for beaver-peltry being slight, and the prices paid out of all proportion to the labor entailed in trapping. It has been said that, if a dam or house be once injured by the hand of man, the colony at once disappears. But that this is fallacious is proved by the following: Twenty-two miles from Marquette, Michigan, on the Carp River, a beaver colony began the erection of a new dam. Though the embankment of a railway ran nearly parallel with the stream, and trains passed backward and forward daily, they seemed in no way disturbed, and worked steadily on until the water had risen a foot or more. The track-master, observing that this endangered the line—for the embankment had been utilized as a wing of the dam—ordered the water drawn off. But the following day the beavers had repaired the damage done them, and the water was at its former height. Again and again and again was the dam cut through, and as often would it be repaired. All in all, it was cut and repaired some fifteen or twenty times ere the beavers were sufficiently discouraged to abandon their attempts.