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animal dies in the plain, the Cathartes atratus or Gallinazo commences the feast,
and then these two carrjon-feeding hawks pick the bones clean. Although
belonging to closely allied genera, and thus commonly feeding together, they are
far from being friends. When the Garrancha is quietly seated on the branch of a
tree, or on the ground, the Chimango often continues flying backwards and forwards
for a long time, np and down in a semicircle, trying each time, at the bottom
of the curve, to strike its larger relative. The Garrancha takes little notice, except
by bobbing its head. Although the Carranchas frequently assemble in numbers,
they are not gregarious ; for in desert places tliey may be seen solitary, or more
commonly by pairs. Besides the carrion of large animals, these birds frequent
the boi'ders of streams and the sea-beach, for the sake ol picking up whatever the
waters may cast on shore. In Tierra del Fuego, and on the west coast of
Patagonia, they must live almost exclusively on this last means of supply.
The Carranchas are said to be very crafty, and to steal great numbers of
e g g s ; they attempt also, together with the Chimango, to pick the scabs oif the
sore backs of both horses and mules. On the one hand, the poor animal,
with its ears down and its back arched; and, on the other, the hovering bird,
eyeing at the distance of a yard, the disgusting morsel, form a picture which has
been described by Captain Head witli his own peculiar spirit and accuracy.
The Carranchas kill wounded animals ; but Mr. Bynoe (the surgeon of the
Beagle) saw one seize in the air a live partridge, which, however, escaped, and
was for some time chased on the ground. I believe , this circumstance is very
unusual: at all events there is no doubt that the chief part of their sustenance is
derived from carrion. A person will discover their necrophagous habits by
walking out on one of the desolate plains, and there lying down to sleep : when
he awakes, he will see on each surrounding hillock, one of these birds patiently
watching him with an evil eye. It is a feature in the landscape of these countries,
which will be recognised by every one who has wandered over them. If a party
goes out hunting with dogs and horses, it will be accompanied during the day, by
several of these attendants. The uncovered craw of the Garrancha, after feeding,
protrudes from its breast; at such times it is, and indeed generally, an inactive,
tame, and cowardly bird. Its flight is generally heavy and slow, like that of the
English carrion crow, whose place it so well supplies in America. It seldom soars;
but I have twice seen one at a great height gliding through the air with much
ease. It runs (in contradistinction to hopping), but not quite so quickly as some
of its congeners. At times the Garrancha is noisy, but is not generally so ; its
cry is loud, very harsh and peculiar, and may he compared to the sound of the
Spanish guttural g , followed by a rough double r r. Perhaps the Spaniards of
Buenos Ayres, from this cause, have called it Garrancha. Molina, who says it is
called Tharu in Chile, states, that when uttering this cry, it elevates its head
higher and higher, till at last, with its beak wide open, the crown almost touches
the lower part of the back. This fact, which has been doubted, is true ; for I have
myself several times seen them with their heads backwards, in a completely
inverted position. The Cariancha builds a large coarse nest, either in a
low cliff, or in a bush or lofty tree. To these observations I may add, on
the high authority of Azara, whose statements have lately been so fully
confirmed by M. D ’Orbigny, that the Carranclia feeds on worms, shells, slugs,
grasshoppers, and frogs ; that it destroys young lambs by tearing the umbilical
cord : and that it pursues the Gallinazos and gulls which attend the slaughtering-
houses, till these birds are compelled to vomit up any carrion they may
have lately gorged. Lastly, Azara states that several Carranchas, five or six
together, will unite in chase of large birds, even such as herons. All these facts
show that it is a bird of very versatile habits and considerable ingenuity.
I am led to suppose that the young birds of this species sometimes congregate
together. On the plains of Santa Cruz (lat. 50° S. in Patagonia), I saw in
the month of April, or early autumn, between twenty and thirty Polybori, which
I at first thought would form a species distinct from P . Brasiliensis. Amongst
those I killed, there were some of both sexes ; but the ovarium in the hens was
only slightly granular. The plumage of the different individuals was nearly
similar ; and in none appeared like that of an adult bird, altliough certainly
not of a very young one. Having mentioned these circumstances to Mr.
Gould, he likewise suspected it would form a new species ; but the differences
appear so trifling between it and the specimens of young birds in the British
Museum and in the Museum of the Zoological Society, and likewise of the figure
of a young bird given by Spix, (Avium Species Novæ, vol. i. p. 3.), that I have
thought it advisable merely to allude to the circumstance. In my specimen,
which is a cock, the head, instead of being of a dark brown, which is the usual
character of even very immature birds, is of a pale rusty brown. The bill and
cere are less produced than in the adult P . Brasiliensis ; and the cere is of a
brighter colour, than what appears to be usuiil in the young of this species. In
other respects there is such a perfect similarity between them, that I do not
liesitate to consider my specimen as a young bird of the P . Brasiliensis in one
of its states of change ;—and to be subject to great variation of plumage during
growth, is known to be a character common to the birds of this sub-family. It
may, however, possibly be some variety of the P . Brasiliensis, for this bird seems
subject to variation : Azara (Voyage dans l’Amérique Méridionale, vol. iii. p. 35.)
remarks, “ II y a des individus dont les teintes sont plus faibles, ou d’un brun
pâle, avec des taches sur la poitrine, et d’autres qui ont des couleurs plus foncées ;
j’ai décrit ceux qui tiennent le milieu entre les uns et les autres.”
I have myself more than once observed a single very pale-coloured bird, in
c 2