CHAPTER XX
.
BIOGRAPHY OF THE VIZCACHA.
_(Lagostomus Trichodactylus.)_
The vizcacha is perhaps the most characteristic of the South American Rodentia, [Footnote: "According to Mr. Waterhouse, of all rodents the vizcacha is most nearly related to marsupials; but in the points in which it approaches this order its relations are general, that is, not to any one marsupial species more than to another. As these points of affinity are believed to be real and not merely adaptive, they must be due in accordance with our view to inheritance from a common progenitor. Therefore wo must suppose either that all rodents, including the vizcacha, branched off from some ancient marsupial, which will naturally have been more or less intermediate in character with respect to all existing marsupials; or, that both lodents and marsupials branched off from a common progenitor. ... On either view we must suppose that the vizcacha has retained, by inheritance, more of the characters of its ancient progenitor than have other rodents."--DARWIN; _Origin of Species._] while its habits, in some respects, are more interesting than those of any other rodent known: it is, moreover, the most common mammal we have on the pampas; and all these considerations have induced me to write a very full account of its customs. It is necessary to add that since the following pages were written at my home on the pampas a great war of extermination has been waged against this animal by the landowners, which has been more fortunate in its results--or unfortunate if one's sympathies are with the vizcacha--than the war of the Australians against their imported rodent--the smaller and more prolific rabbit.
The vizcachas on the pampas of Buenos Ayres live in societies, usually numbering twenty or thirty members. The village, which is called Vizcachera, is composed of a dozen or fifteen burrows or mouths; for one entrance often serves for two or more distinct holes. Often, where the ground is soft, there are twenty or thirty or more burrows in an old vizcachera; but on stony, or "tosca" soil even an old one may have no more than four or five burrows. They are deep wide-mouthed holes, placed very close together, the entire village covering an area of from one hundred to two hundred square feet of ground.
The burrows vary greatly in extent; and usually in a vizcachera there are several that, at a distance of from four to six feet from the entrance, open into large circular chambers. From these chambers other burrows diverge in all directions, some running horizontally, others obliquely downwards to a maximum depth of six feet from the surface: some of these burrows or galleries communicate with those of other burrows. A vast amount of loose earth is thus brought up, and forms a very irregular mound, fifteen to thirty inches above the surrounding level.
It will afford some conception of the numbers of these vizcacheras on the settled pampas when I say that, in some directions, a person might ride five hundred miles and never advance half a mile without seeing one or more of them. In districts where, as far as the eye can see, the plains are as level and smooth as a bowling-green, especially in winter when the grass is close-cropped, and where the rough giant-thistle has not sprung up, these mounds appear like brown or dark spots on a green surface. They are the only irregularities that occur to catch the eye, and consequently form an important feature in the scenery. In some places they are so near together that a person on horseback may count a hundred of them from one point of view.
The sites of which the vizcacha invariably makes choice to work on, as well as his manner of burrow-ing, adapt him peculiarly to live and thrive on the open pampas. Other burrowing species seem always to fix upon some spot where there is a bank or a sudden depression in the soil, or where there is rank herbage, or a bush or tree, about the roots of which to begin their kennel. They are averse to commence digging on a clear level surface, either because it is not easy for them where they have nothing to rest their foreheads against while scratching, or because they possess a wary instinct that impels them to place the body in concealment whilst working on the surface, thus securing the concealment of the burrow after it is made. Certain it is that where large hedges have been planted on the pampas, multitudes of opossums, weasels, skunks, armadillos, &c., come and make their burrows beneath them; and where there are no hedges or trees, all these species make their kennels under bushes of the perennial thistle, or where there is a shelter of some kind. The vizcacha, on the contrary, chooses an open level spot, the cleanest he can find to burrow on. The first thing that strikes the observer when viewing the vizcachera closely is the enormous size of the entrance of the burrows, or, at least, of several of the central ones in the mound; for there are usually several smaller outside burrows. The pit-like opening to some of these principal burrows is often four to six feet across the mouth, and sometimes deep enough for a tall man to stand up waist-deep in. How these large entrances can be made on a level surface may be seen when the first burrow or burrows of an incipient vizcachera are formed. It is not possible to tell what induces a vizcacha to be the founder of a new community; for they increase very slowly, and furthermore are extremely fond of each other's society; and it is invariably one individual that leaves his native village to found a new and independent one. If it were to have better pasture at hand, then he would certainly remove to a considerable distance; but he merely goes from forty to fifty or sixty yards off to begin his work. Thus it is that in desert places, where these animals are rare, a solitary vizcachera is never seen; but there are always several close together, though there may be no others on the surrounding plain for leagues. When the vizcacha has made his habitation, it is but a single burrow, with only himself for an inhabitant, perhaps for many months. Sooner or later, however, others join him: and these will be the parents of innumerable generations; for they construct no temporary lodging-place, as do the armadillos and other species, but their posterity continues in the quiet possession of the habitations bequeathed to it; how long, it is impossible to say. Old men who have lived all their lives in one district remember that many of the vizcacheras around them existed when they were children. It is invariably a male that begins a new village, and makes his burrow in the following manner, though he does not always observe the same method. He works very straight into the earth, digging a hole twelve or fourteen inches wide, but not so deep, at an angle of about 25 degrees with the surface. But after he has progressed inwards a few feet, the vizcacha is no longer satisfied with merely scattering away the loose earth he fetches up, but cleans it away so far in a straight line from the entrance, and scratches so much on this line (apparently to make the slope gentler), that he soon forms a trench a foot or more in depth, and often three or four feet in length. Its use is, as I have inferred, to facilitate the conveying of the loose earth as far as possible from the entrance of the burrow. But after a while the animal is unwilling that it should accumulate even at the end of this long passage; he therefore proceeds to make two additional trenches, that form an acute, sometimes a right angle, converging into the first, so that when the whole is completed it takes the form of a capital Y.
These trenches are continually deepened and lengthened as the burrow progresses, the angular segment of earth between them, scratched away, until by degrees it has been entirely conveyed off, and in its place is the one deep great unsymmetrical mouth I have already described. There are soils that will not admit of the animals working in this manner. Where there are large cakes of "tosca" near the surface, as in many localities on the southern pampas, the vizcacha makes its burrow as best he can, and without the regular trenches. In earths that crumble much, sand or gravel, he also works under great disadvantages.
The burrows are made best in the black and red moulds of the pampas; but even in such soils the entrances of many burrows are made differently. In some the central trench is wanting, or is so short that there appear but two passages converging directly into the burrow; or these two trenches may be so curved inwards as to form the segment of a circle. Many other forms may also be noticed, but usually they appear to be only modifications of the most common Y-shaped system.
As I have remarked that its manner of burrowing has peculiarly adapted the vizcacha to the pampas, it may be asked what particular advantage a species that makes a wide-mouthed burrow possesses over those that excavate in the usual way. On a declivity, or at the base of rocks or trees, there would be none; but on the perfectly level and shelterless pampas, the durability of the burrow, a circumstance favourable to the animal's preservation, is owing altogether to its being made in this way, and to several barrows being made together. The two outer trenches diverge so widely from the mouth that half the earth brought out is cast behind instead of before it, thus creating a mound of equal height about the entrance, by which it is secured from water during great rainfalls, while the cattle avoid treading over the great pit-like entrances. But the burrows of the dolichotis, armadillo, and other species, when made on perfectly level ground, are soon trod on and broken in by cattle; in summer they are choked up with dust and rubbish; and, the loose earth having all been thrown up together in a heap on one side, there is no barrier to the water which in every great rainfall flows in and obliterates the kennel, drowning or driving out the tenant.
I have been minute in describing the habitations of the vizcacha, as I esteem the subject of prime importance in considering the zoology of this portion of America. The vizcacha does not benefit himself alone by his perhaps unique style of burrowing; but this habit has proved advantageous to several other species, and has been so favourable to two of our birds that they are among the most common species found here, whereas without these burrows they would have been exceedingly rare, since the natural banks in which they breed are scarcely found anywhere on the pampas. I refer to the Minera (Geositta cunicularia), which makes its breeding-holes in the bank-like sides of the vizcacha's burrow, and to the little swallow (Atticora cyanoleuca) which breeds in these excavations when forsaken by the Minera. Few old vizcacheras are seen without some of these little parasitical burrows in them.
Birds are not the only beings in this way related to the vizcachas: the fox and the weasel of the pampas live almost altogether in them. Several insects also frequent these burrows that are seldom found anywhere else. Of these the most interesting are:--a large predacious nocturnal bug, shining black, with red wings; a nocturnal Cicindela, a beautiful insect, with dark green striated wing-cases and pale red legs; also several diminutive wingless wasps. Of the last I have counted six species, most of them marked with strongly contrasted colours, black, red, and white. There are also other wasps that prey on the spiders found on the vizcachera. All these and others are so numerous on the mounds that dozens of them might there be collected any summer day; but if sought for in other situations they are exceedingly rare. If the dry mound of soft earth which the vizcacha elevates amidst a waste of humid, close-growing grass is not absolutely necessary to the existence of all these species, it supplies them with at least one favourable condition, and without doubt thereby greatly increases their numbers: they, too, whether predacious or preyed on, have so many relations with other outside species, and these again with still others, that it would be no mere fancy to say that probably hundreds of species are either directly or indirectly affected in their struggle for existence by the vizcacheras so abundantly sprinkled over the pampas.
In winter the vizcachas seldom leave their burrows till dark, but in summer come out before sunset; and the vizcachera is then a truly interesting spectacle. Usually one of the old males first appears, and sits on some prominent place on the mound, apparently in no haste to begin his evening meal. When approached from the front he stirs not, but eyes the intruder with a bold indifferent stare. If the person passes to one side, he deigns not to turn his head.
Other vizcachas soon begin to appear, each one quietly taking up his station at his burrow's mouth, the females, known by their greatly inferior size and lighter grey colour, sitting upright on their haunches, as if to command a better view, and indicating by divers sounds and gestures that fear and curiosity struggles in them for mastery; for they are always wilder and sprightlier in their motions than the males. With eyes fixed on the intruder, at intervals they dodge the head, emitting at the same time an internal note with great vehemence; and suddenly, as the danger comes nearer, they plunge simultaneously, with a startled cry, into their burrows. But in some curiosity is the strongest emotion; for, in spite of their fellow's contagious example, and already half down the entrance, again they start up to scrutinize the stranger, and will then often permit him to walk within five or six paces of them.
Standing on the mound there is frequently a pair of burrowing owls (Pholeoptynx cunicularia). These birds generally make their own burrows to breed in, or sometimes take possession of one of the lesser outside burrows of the village; but their favourite residence, when not engaged in tending their eggs or young, is on the vizcachera. Here a pair will sit all day; and I have often remarked a couple close together on the edge of the burrow; and when the vizcacha came out in the evening, though but a hand's breadth from them, they did not stir, nor did he notice them, so accustomed are these creatures to each other. Usually a couple of the little burrowing Geositta are also present. They are lively creatures, running with great rapidity about the mound and bare space that surrounds it, suddenly stopping and jerking their tails in a slow deliberate manner, and occasionally uttering their cry, a trill, or series of quick short clear notes, resembling somewhat the shrill excessive laughter of a child. Among the grave, stationary vizcachas, of which they take no heed, perhaps half a dozen or more little swallows (Atticora cyanoleuca) are seen, now clinging altogether to the bank-like entrance of a burrow, now hovering over it in a moth-like manner, as if uncertain where to alight, and anon sweeping about in circles, but never ceasing their low and sorrowful notes.
The vizcachera with all its incongruous inhabitants thus collected upon it is to a stranger one of the most novel sights the pampas afford.
The vizcacha appears to be a rather common species over all the extensive Argentine territory; but they are so exceedingly abundant on the pampas inhabited by man, and comparatively so rare in the desert places I have been in, that I was at first much surprised at finding them so unequally distributed. I have also mentioned that the vizcacha is a tame familiar creature. This is in the pastoral districts, where they are never disturbed; but in wild regions, where he is scarce, he is exceedingly wary, coming forth long after dark, and plunging into his burrow on the slightest alarm, so that it is a rare thing to get a sight of him. The reason is evident enough; in desert regions the vizcacha has several deadly enemies in the larger rapacious mammals. Of these the puma or lion (Felis concolor) is the most numerous, as it is also the swiftest, most subtle, and most voracious; for, as regards these traits, the jaguar (F. onca) is an inferior animal. To the insatiable bloody appetite of this creature nothing comes amiss; he takes the male ostrich by surprise, and slays that wariest of wild things on his nest; He captures little birds with the dexterity of a cat, and hunts for diurnal armadillos; he comes unawares upon the deer and huanaco, and, springing like lightning on them, dislocates their necks before their bodies touch the earth. Often after he has thus slain them, he leaves their bodies untouched for the Polyborus and vulture to feast on, so great a delight does he take in destroying life. The vizcacha falls an easy victim to this subtle creature; and it is not to be wondered at that it becomes wild to excess, and rare in regions hunted over by such an enemy, even when all other conditions are favourable to its increase. But as soon as these wild regions are settled by man the pumas are exterminated, and the sole remaining foe of the vizcacha is the fox, comparatively an insignificant one.
The fox takes up his residence in a vizcachera, and succeeds, after some quarrelling (manifested in snarls, growls, and other subterranean warlike sounds), in ejecting the rightful owners of one of the burrows, which forthwith becomes his. Certainly the vizcachas are not much injured by being compelled to relinquish the use of one of their kennels for a season or permanently; for, if the locality suits him, the fox remains with them always. Soon they grow accustomed to the unwelcome stranger; he is quiet and unassuming in demeanour, and often in the evening sits on the mound in their company, until they regard him with the same indifference they do the burrowing owl. But in spring, when the young vizcachas are large enough to leave their cells, then the fox makes them his prey; and if it is a bitch fox, with a family of eight or nine young to provide for, she will grow so bold as to hunt her helpless quarry from hole to hole, and do battle with the old ones, and carry off the young in spite of them, so that all the young animals in the village are eventually destroyed. Often when the young foxes are large enough to follow their mother, the whole family takes leave of the vizcachera where such cruel havoc has been made to settle in another, there to continue their depredations. But the fox has ever a relentless foe in man, and meets with no end of bitter persecutions; it is consequently much more abundant in desert or thinly settled districts than in such as are populous, so that in these the check the vizcachas receive from the foxes is not appreciable.
The abundance of cattle on the pampas has made it unnecessary to use the vizcacha as an article of food. His skin is of no value; therefore man, the destroyer of his enemies, has hitherto been the greatest benefactor of his species. Thus they have been permitted to multiply and spread themselves to an amazing extent, so that the half-domestic cattle on the pampas are not nearly so familiar with man, or so fearless of his presence as are the vizcachas. It is not that they do him no injury, but because they do it indirectly, that they have so long enjoyed immunity from persecution. It is amusing to see the sheep-farmer, the greatest sufferer from the vizcachas, regarding them with such indifference as to permit them to swarm on his "run," and burrow within a stone's throw of his dwelling with impunity, and yet going a distance from home to persecute with unreasonable animosity a fox, skunk, or opossum on account of the small annual loss it inflicts on the poultry-yard. That the vizcacha has comparatively no adverse conditions to war with wherever man is settled is evident when we consider its very slow rate of increase, and yet see them in such incalculable numbers. The female has but one litter in the year of two young, sometimes of three. She becomes pregnant late in April, and brings forth in September; the period of gestation is, I think, rather less than five months.
The vizcacha is about two years growing. A full-sized male measures to the root of the tail twenty-two inches, and weighs from fourteen to fifteen pounds; the female is nineteen inches in length, and her greatest weight nine pounds. Probably it is a long-lived, and certainly it is a very hardy animal. Where it has any green substance to eat it never drinks water; but after a long summer drought, when for months it has subsisted on bits of dried thistle-stalks and old withered grass, if a shower falls it will come out of its burrows even at noonday and drink eagerly from the pools. It has been erroneously stated that vizcachas subsist on roots. Their food is grass and seeds; but they may also sometimes eat roots, as the ground is occasionally seen scratched up about the burrows. In March, when the stalks of the perennial cardoon or Castile thistle (Cynara cardunculus) are dry, the vizcachas fell them by gnawing about their roots, and afterwards tear to pieces the great dry flower-heads to get the seeds imbedded deeply in them, of which they seem very fond. Large patches of thistle are often found served thus, the ground about them literally white with the silvery bristles they have scattered. This cutting down tall plants to get the seeds at the top seems very like an act of pure intelligence; but the fact is, the vizcachas cut down every tall plant they can. I have seen whole acres of maize destroyed by them, yet the plants cut down were left untouched. If posts be put into the ground within range of their nightly rambles they will gnaw till they have felled them, unless of a wood hard enough to resist their chisel-like incisors.
The strongest instinct of this animal is to clear the ground thoroughly about its burrows; and it is this destructive habit that makes it necessary for cultivators of the soil to destroy all the vizcachas in or near their fields. On the uninhabited pampas, where the long grasses grow, I have often admired the vizcachera; for it is there the centre of a clean space, often of half an acre in extent, on which there is an even close-shaven turf: this clearing is surrounded by the usual rough growth of herbs and giant grasses. In such situations this habit of clearing the ground is eminently advantageous to them, as it affords them a comparatively safe spot to feed and disport themselves on, and over which they can fly to their burrows without meeting any obstruction, on the slightest alarm.
Of course the instinct continues to operate where it is no longer of any advantage. In summer, when the thistles are green, even when growing near the burrows, and the giant thistle (Carduus mariana) springs up most luxuriantly right on the mound, the vizcachas will not touch them, either disliking the strong astringent sap, or repelled by the thorns with which they are armed. As soon as they dry, and the thorns become brittle, they are levelled; afterwards, when the animal begins to drag them about and cut them up, as his custom is, he accidentally discovers and feasts on the seed: for vizcachas are fond of exercising their teeth on hard substances, such as sticks and bones, just as cats are of "sharpening their claws" on trees.
Another remarkable habit of the vizcacha, that of dragging to and heaping about the mouth of his burrow every stalk he cuts down, and every portable object that by dint of great strength he can carry, has been mentioned by Azara, Darwin, and others. On the level plains it is a useful habit; for as the vizcachas are continually deepening and widening their burrows, the earth thrown out soon covers up these materials, and so assists in raising the mound. On the Buenos-Ayrean pampas numbers of vizcacheras would annually be destroyed by water in the great sudden rainfalls were the mounds loss high. But this is only an advantage when the animals inhabit a perfectly level country subject to flooding rains; for where the surface is unequal they invariably prefer high to low ground to burrow on, and are thus secured from destruction by water; yet the instinct is as strong in such situations as on the level plains. The most that can be said of a habit apparently so obscure in its origin and uses is, that it appears to be part of the instinct of clearing the ground about the village. Every tall stalk the vizcacha cuts down, every portable object he finds, must be removed to make the surface clean and smooth; but while encumbered with it he does not proceed further from his burrows, but invariably re-tires towards them, and so deposits it upon the mound. So well known is this habit, that whatever article is lost by night--whip, pistol, or knife--the loser next morning visits the vizcacheras in the vicinity, quite sure of finding it there. People also visit the vizcacheras to pick up sticks for firewood.
The vizcachas are cleanly in their habits; and the fur, though it has a strong earthy smell, is kept exceedingly neat. The hind leg and foot afford a very beautiful instance of adaptation. Propped by the hard curved tail, they sit up erect, and as firmly on the long horny disks on the undersides of the hind legs as a man stands on his feet. Most to be admired, on the middle toe the skin thickens into a round cushion, in which the curved teeth-like bristles are set; nicely graduated in length, so that "each particular hair" may come into contact with the skin when the animal scratches or combs itself. As to the uses of this appendage there can be no difference of opinion, as there is about the serrated claw in birds. It is quite obvious that the animal cannot scratch himself with his hind paw (as all mammals do) without making use of this natural comb. Then the entire foot is modified, so that this comb shall be well protected, and yet not be hindered from performing its office: thus the inner toe is pressed close to the middle one, and so depressed that it comes under the cushion of skin, and cannot possibly get before the bristles, or interfere their coming against the skin in scratching, as certainly be the case if this toe were free as outer one.
Again, the vizcachas appear to form the deep trenches before the burrows by scratching the earth violently backwards with the hind claws. Now these straight, sharp, dagger-shaped claws, and especially the middle one, are so long that the vizcacha is able to perform all this rough work without the bristles coming into contact with the ground, and so getting worn by the friction. The Tehuelcho Indians in Patagonia comb their hair with a brush-comb very much like that on the vizcacha's toe, but in their case it does not properly fulfil its office, or else the savages make little use of it. Vizcachas have a remarkable way of dusting themselves: the animal suddenly throws himself on his back, and, bringing over his hind legs towards his head, depresses them till his feet touch the ground. In this strange posture he scratches up the earth with great rapidity, raising a little cloud of dust, then rights himself with a jerk, and, after an interval, repeats the dusting. Usually they scratch a hole in the ground to deposit their excrements in. Whilst opening one of the outside burrows that had no communication with the others, I once discovered a vast deposit of their dung (so great that it must have been accumulating for years) at the extremity. To ascertain whether this be a constant, or only a casual habit, it would be necessary to open up entirely a vast number of vizcacheras. When a vizcacha dies in his burrow the carcass is, after some days, dragged out and left upon the mound.
The language of the vizcacha is wonderful for its variety. When the male is feeding he frequently pauses to utter a succession of loud, percussive, and somewhat jarring cries; these he utters in a leisurely manner, and immediately after goes on feeding. Often he utters this cry in a low grunting tone. One of his commonest expressions sounds like the violent hawking of a man clearing his throat. At other times he bursts into piercing tones that may be heard a mile off, beginning like the excited and quick-repeated squeals of a young pig, and growing longer, more attenuated, and quavering towards the end. After retiring alarmed into the burrows, he repeats at intervals a deep internal moan. All these, and many other indescribable guttural, sighing, shrill, and deep tones, are varied a thousand ways in strength and intonation, according to the age, sex, or emotions of the individual; and I doubt if there is in the world any other four-footed thing so loquacious, or with a dialect so extensive. I take great pleasure in going to some spot where they are abundant, and sitting quietly to listen to them; for they are holding a perpetual discussion, all night long, which the presence of a human being will not interrupt.
At night, when the vizcachas are all out feeding, in places where they are very abundant (and in some districts they literally swarm) any very loud and sudden sound, as the report of a gun, or a clap of unexpected thunder, will produce a most extraordinary effect. No sooner has the report broken on the stillness of night than a perfect storm of cries bursts forth over the surrounding country. After eight or nine seconds there is in the storm a momentary hill or pause; and then it breaks forth again, apparently louder than before. There is so much difference in the tones of different animals that the cries of individuals close at hand may be distinguished amidst the roar of blended voices coming from a distance. It sounds as if thousands and tens of thousands of them were striving to express every emotion at the highest pitch of their voices; so that the effect is indescribable, and fills a stranger with astonishment. Should a gun be fired off several times, their cries become less each time; and after the third or fourth time it produces no effect. They have a peculiar, sharp, sudden, "far-darting" alarm-note when a dog is spied, that is repeated by all that hear it, and produces an instantaneous panic, sending every vizcacha flying to his burrow.
But though they manifest such a terror of dogs when out feeding at night (for the slowest dog can overtake them), in the evening, when sitting upon their mounds, they treat them with tantalizing contempt. If the dog is a novice, the instant he spies the animal he rushes violently at it; the vizcacha waits the charge with imperturbable calmness till his enemy is within one or two yards, and then disappears into the burrow. After having been foiled in this way many times, the dog resorts to stratagem: he crouches down as if transformed for the nonce into a Felis, and steals on with wonderfully slow and cautious steps, his hair bristling, tail hanging, and eyes intent on his motionless intended victim; when within seven or eight yards he makes a sudden rush, but invariably with the same dis-appointing result. The persistence with which the dogs go on hoping against hope in this unprofitable game, in which they always act the stupid part, is highly amusing, and is very interesting to the naturalist; for it shows that the native dogs on the pampas have developed a very remarkable instinct, and one that might be perfected by artificial selection; but dogs with the hunting habits of the cat would, I think, be of little use to man. When it is required to train dogs to hunt the nocturnal armadillo (Dasypus villosus), then this deep-rooted (and, it might be added, hereditary) passion for vizcachas is excessively annoying, and it is often necessary to administer hundreds of blows and rebukes before a dog is induced to track an armadillo without leaving the scent every few moments to make futile grabs at his old enemies.
The following instance will show how little suspicion of man the vizcachas have. A few years ago I went out shooting them on three consecutive evenings. I worked in a circle, constantly revisiting the same burrows, never going a greater distance from home than could be walked in four or five minutes. During the three evenings I shot sixty vizcachas dead; and probably as many more escaped badly wounded into their burrows; for they are hard to kill, and however badly wounded, if sitting near the burrow when struck, are almost certain to escape into it. But on the third evening I found them no wilder, and killed about as many as on the first. After this I gave up shooting them in disgust; it was dull sport, and to exterminate or frighten them away with a gun seemed an impossibility.
It is a very unusual thing to eat the vizcacha, most people, and especially the gauchos, having a silly unaccountable prejudice against their flesh. I have found it very good, and while engaged writing this chapter have dined on it served up in various ways. The young animals are rather insipid, the old males tough, but the mature females are excellent--the flesh being tender, exceedingly white, fragrant to the nostrils, and with a very delicate game-flavour.
Within the last ten years so much new land has been brought under cultivation that farmers have been compelled to destroy incredible numbers of vizcachas: many large "estancieros" (cattle-breeders) have followed the example set by the grain-growers, and have had them exterminated on their estates. Now all that Azara, on hearsay, tells about the vizcachas perishing in their burrows, when these are covered up, but that they can support life thus buried for a period of ten or twelve days, and that during that time animals will come from other villages and disinter them, unless frightened off with dogs, is strictly true. Country workmen are so well acquainted with these facts that they frequently undertake to destroy all the vizcacheras on an estate for so paltry a sum as ten-pence in English money for each one, and yet will make double the money at this work than they can at any other. By day they partly open up, then cover up the burrows with a great quantity of earth, and by night go round with dogs to drive away the vizcachas from the still open burrows that come to dig out their buried friends. After all the vizcacheras on an estate have been thus served, the workmen are usually bound by previous agreement to keep guard over them for a space of eight or ten days before they receive their hire: for the animals covered up are then supposed to be all dead. Some of these men I have talked with have assured me that living vizcachas have been found after fourteen days--a proof of their great endurance. There is nothing strange, I think, in the mere fact of the vizcacha being unable to work his way out when thus buried alive; for, for all I know to the contrary, other species may, when their burrows are well covered up, perish in the same manner; but it certainly is remarkable that other vizcachas should come from a distance to dig out those that are buried alive. In this good office they are exceedingly zealous; and I have frequently surprised them after sunrise, at a considerable distance from their own burrows, diligently scratching at those that had been covered up. The vizcachas are fond of each other's society, and live peaceably together; but their goodwill is not restricted to the members of their own little community; it extends to the whole species, so that as soon as night comes many animals leave their own and go to visit the adjacent villages. If one approaches a vizcachera at night, usually some of the vizcachas on it scamper off to distant burrows: these are neighbours merely come to pay a friendly visit. This intercourse is so frequent that little straight paths are formed from one vizcachera to another. The extreme attachment between members of different communities makes it appear less strange that they should assist each other: either the desire to see, as usual, their buried neighbours becomes intense enough to impel them to work their way to them; or cries of distress from the prisoners reach and incite them to attempt their deliverance. Many social species are thus powerfully affected by cries of distress from one of their fellows; and some will attempt a rescue in the face of great danger--the weasel and the peccary for example.
Mild and sociable as the vizcachas are towards each other, each one is exceedingly jealous of any intrusion into his particular burrow, and indeed always resents such a breach of discipline with the utmost fury. Several individuals may reside in the compartments of the same burrow; but beyond themselves not even their next-door neighbour is permitted to enter; their hospitality ends where it begins, at the entrance. It is difficult to compel a vizcacha to enter a burrow not his own; even when hotly pursued by dogs they often refuse to do so. When driven into one, the instant their enemies retire a little space they rush out of it, as if they thought the hiding-place but little less dangerous than the open plain. I have frequently seen vizcachas, chased into the wrong burrows, summarily ejected by those inside: and sometimes they make their escape only after being well bitten for their offence.
I have now stated the most interesting facts I have collected concerning the vizcacha: when others rewrite its history they doubtless will, according to the opportunities of observation they enjoy, be able to make some additions to it, but probably none of great consequence. I have observed this species in Patagonia and Buenos Ayres only; and as I have found that its habits are considerably modified by circumstances in the different localities where I have met with it, I am sure that other variations will occur in the more distant regions, where the conditions vary.
The most remarkable thing to be said about the vizcacha is, that although regarded by Mr. Waterhouse, and others who have studied its affinities, as one of the lowest of the rodents, exhibiting strong Marsupial characters, the living animal appears to be more intelligent than other rodents, not of South America only, but also of those of a higher type in other continents. A parallel case is, perhaps, to be found in the hairy armadillo, an extremely versatile and intelligent animal, although only an edentate. And among birds the ypecaha--a large La Plata rail--might also be mentioned as an example of what ought not to be; for it is a bold and intelligent bird, more than a match for the fowl, both in courage and in cunning; and yet it is one of the family which Professor Parker--from the point of view of the anatomist--characterizes as a "feeble-minded, cowardly group."
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