(CARANCHO CARRION-HAWK.)
Polyborus vulgaris, Burm. La-Plata Reise, ii. p. 434 (La Plata); Durnford, Ibis, 1877, p. 40 (Chupat). Polyborus tharus, Scl. et Salv. Nomencl. p. 123; Durnford, Ibis, 1877, p. 188 (Buenos Ayres), et 1878, p. 398 (Centr. Patagonia); Gibson, Ibis, 1879, p. 415 (Buenos Ayres); White, P. Z. S. 1883, p. 41 (Cordova); Barrows, Auk, 1884, p. 111 (Entrerios); Sharpe, Cat. B. i. p. 31. Polyborus brasiliensis, Darwin, Zool. Beagle, iii. p. 9.
Description.—Above dark brown with whitish mottlings; head blackish; wings and tail greyish white, with numerous greyish-brown cross bars and blackish tips: beneath dark brown, varied with white; throat and sides of head fulvous white; bill yellow, bluish at the base; cere orange; feet brown; claws black: whole length 20 inches, wing 15·5, tail 9·0. Female similar.
Hab. South America.
This bird, which combines the raptorial instincts of the Eagle with the base carrion-feeding propensities of the Vulture, has already had so many biographers that it might seem superfluous to speak again at any great length of it; only it happens to be one of those very versatile species about which there is always something fresh to be said; and, besides, I do not altogether agree with the very ignoble character usually ascribed to it by travellers. It is, however, probable that it varies greatly in disposition and habits in different districts. In Patagonia I was surprised at its dejected appearance and skulking cowardly manner, so unlike the bird I had been accustomed to see on the pampas. I shot several, and they were all in a miserably poor condition and apparently half-starved. It struck me that in that cold sterile country, where prey is scarce, the Carancho is altogether out of place; for it there has to compete with Eagles and Vultures in large numbers; and these, it is almost needless to say, are, in their separate lines, stronger than the composite and less specialized Carancho. In Patagonia he is truly a “miserable bird,” with a very frail hold on existence. How different on that illimitable grassy ocean further north, where he is the lord of the feathered race, for Eagles and Vultures, that require mountains and trees to breed and roost on, do not come there to set him aside; there the conditions are suited to him and have served to develop in him a wonderfully bold and savage spirit. When seen perched on a conical ant-hill, standing erect above the tall plumy grass, he has a fine, even a noble, appearance; but when flying he is not handsome, the wings being very bluntly rounded at the extremities and the flight low and ungraceful. The plumage is blackish in the adult, brown in the young. The sides of the head and breast are creamy white, the latter transversely marked with black spots. The crown is adorned with a crest or top-knot. The beak is much larger than in Eagles and Vultures, and of a dull blue colour; the cere and legs are bright yellow.
The species ranges throughout South America, and from Paraguay northwards is called everywhere, I believe, “Caracara.” South of Paraguay the Spanish name is “Carancho,” possibly a corruption of “Keanché,” the Puelche name for the allied Milvago chimango, in imitation of its peevish cry. The Indian name for the Carancho in these regions is Trarú (from its harsh cry), misspelt tharú by Molina.
The Caranchos pair for life, and may therefore be called social birds; they also often live and hunt in families of the parent and young birds until the following spring; and at all times several individuals will readily combine to attack their prey, but they never live or move about in flocks. Each couple has its own home or resting-place, which they will continue to use for an indefinite time, roosting on the same branch and occupying the same nest year after year; while at all times the two birds are seen constantly together and seem very much attached. Azara relates that he once saw a male pounce down on a frog, and carrying it to a tree call his mate to him and make her a present of it. It was not a very magnificent present, but the action seems to show that the bird possesses some commendable qualities which are seldom seen in the raptorial family.
In uninhabited places I have always found the Caranchos just as abundant as in the settled districts; and after a deer has been pulled down by the dogs I have seen as many as seventy or eighty birds congregate to feed on its flesh within half an hour, although not one had been previously visible. D’Orbigny describes the bird as a parasite on man, savage and civilized, following him everywhere to feed on the leavings when he slays wild or domestic animals, and as being scarcely able to exist without him. No doubt the bird does follow man greatly to its advantage, but this is only in very thinly settled and purely pastoral and hunting districts, where a large proportion of the flesh of every animal slain is given to the fowls of the air. Where the population increases the Carancho quickly meets with the fate of all large species which are regarded as prejudicial.
Without doubt it is a carrion-eater, but only, I believe, when it cannot get fresh provisions; for when famished it will eat anything rather than study its dignity and suffer hunger like the nobler Eagle. I have frequently seen one or two or three of them together on the ground under a column of winged ants, eagerly feasting on the falling insects. To eat putrid meat it must be very hungry indeed; it is, however, amazingly fond of freshly-killed flesh, and when a cow is slaughtered at an estancia-house the Carancho quickly appears on the scene to claim his share, and catching up the first thing he can lift he carries it off before the dogs can deprive him of it. When he has risen to a height of five or six yards in the air he drops the meat from his beak and dexterously catches it in his claws without pausing or swerving in his flight. It is singular that the bird seems quite incapable of lifting anything from the ground with the claws, the beak being invariably used, even when the prey is an animal which it might seem dangerous to lift in this way. I once saw one of these birds swoop down on a rat from a distance of about forty feet, and rise with its struggling and squealing prey to a height of twenty feet, then drop it from its beak and gracefully catch it in its talons. Yet when it pursues and overtakes a bird in the air it invariably uses the claws in the same way as other Hawks. This I have frequently observed, and I give the two following anecdotes to show that even birds which one would imagine to be quite safe from the Carancho are on some occasions attacked by it.
While walking in a waste field near my home one day I came on a Pigeon feeding, and at once recognized it as one which had only began to fly about a week before; for although a large number of Pigeons were kept, this bird happened to be of the purest unspotted white, and for a long time I had been endeavouring to preserve and increase the pure white individuals, but with very little success, for the Peregrines invariably singled them out for attack. A Carancho was circling about at some distance overhead, and while I stood still to watch and admire my Pigeon it stooped to within twenty yards of the surface and remained hovering over my head. Presently the Pigeon became alarmed and flew away, whereupon the Hawk gave chase—a very vain chase I imagined it would prove. It lasted for about half a minute, the Pigeon rushing wildly round in wide circles, now mounting aloft and now plunging downwards close to the surface, the Carancho hotly following all the time. At length, evidently in great terror, the hunted bird flew down, alighting within a yard and a half of my feet. I stooped to take hold of it, when, becoming frightened at my action, it flew straight up and was seized in the talons of its pursuer close to my face and carried away.