Argentine Ornithology - LightNovelsOnl.com
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_Description._--Above cinereous; secondaries edged externally and tipped with white; tail dark cinereous, the four external rectrices with the whole outer webs and about the one-third apical part of the inner webs white, the median rectrices tipped with white; below paler cinereous; throat greyish white, slightly striated with dark cinereous; lower belly, crissum, flanks, and under wing-coverts while, more or less tinged with cinnamomeous; bill and feet black: whole length 90 inches, wing 53, tail 40. _Female_ similar.
_Hab._ Argentina, Patagonia, Chili, and Bolivia.
This _Agriornis_ was obtained by Durnford at Tombo Point in Central Patagonia, by Burmeister in the Sierra de Uspallata, near Mendoza, and by Barrows in the rocky gorges of the Sierra de la Ventana.
Darwin tells us of this species that it "is a scarce, shy, solitary bird, frequenting the valleys in which thickets grow, but often feeding on the ground. In the interior plains of Patagonia, on the banks of the Santa Cruz, I several times saw it chasing beetles on the wing, in a peculiar manner, half hopping and half flying; when thus employed it spreads its tail, and the white feathers in it are displayed in a very conspicuous manner. I also met with the species in the lofty and arid valleys on the eastern side of the Cordillera of Central Chili, and likewise at Copiapo." (Zool. Voy. 'Beagle,' iii. p. 57.)
111. MYIOTHERETES RUFIVENTRIS (Vieill.).
(CHOCOLATE TYRANT.)
+Myiotheretes rufiventris+, _Scl. et Salv. P. Z. S._ 1868, pp. 138, 141 (Conchitas); _iid. Nomencl._ p. 42; _Durnford, Ibis_, 1877, p. 175 (Buenos Ayres), et 1878, p. 394 (Centr. Patagonia); _White, P. Z. S._ 1882, p. 603 (Buenos Ayres); _Barrows, Bull.
Nutt. Orn. Cl._ viii. p. 140 (Entrerios). +Taenioptera variegata+, _Burm. P. Z. S._ 1868, p. 635 (Buenos Ayres), _Hudson, P. Z. S._ 1870, pp. 333, 545, et 1871, p. 260 (Buenos Ayres).
_Description._--Above and below smoky grey, clear on the head and breast; belly, crissum, and under wing-coverts bright rufous; wings black, inner secondaries bright chestnut terminated with white, outer secondaries black, tipped with white; wing-coverts grey, margined with white; tail black, outer margins of external pair of rectrices and tips of all whitish; two outer primaries emarginated; bill and feet black: whole length 95 inches, wing 67, tail 38.
_Female_ similar, but outer primaries not emarginated.
_Hab._ Patagonia, Argentina, and Paraguay.
There is a striking resemblance to a Thrush in this species, when one sees it running on the ground with its beak somewhat elevated; but when it stands or perches, opening and closing its broad tail with a graceful fan-like motion, the resemblance to the stiff automatic _t.u.r.dus_ grows less, and when it flies vanishes altogether--its long wings being as sharply pointed as those of the Peregrine Falcon, while its motions in the air have a Gull-like grace and buoyancy.
It is a very pretty bird; the upper plumage is grey tinged with rufous, the throat pure dark grey, breast and belly rufous, wing-coverts light silvery grey, remiges and rectrices dark. Azara cla.s.sed it under the name of _Pepoaza_ (banded-wing) with the _Taeniopterae_, to which it comes very near in form, flight, language, and habits, though it has longer legs and runs more on the ground. Its summer home is in Southern Patagonia, but its breeding-habits are not known; in winter it migrates north, and in May is found scattered over the pampas, where it is usually called by the country people 'Chorlo,' a name for all Plovers; for while running swiftly about on the ground, often a.s.sociating with flocks of Plover, it has a certain resemblance to them. From the hue of its plumage it is also called 'El Chocolate,' a name I have thought it best to preserve.
These birds are very sociable, going in small flocks, usually of from half a dozen to twenty individuals; they are restless and active, and quick and graceful in all their movements, and seek their food on the ground, chiefly coleopterous insects, on the great level plains they inhabit. While on the wing they pursue each other playfully in the air, and also attack and chase pa.s.sing birds of other kinds, apparently in a sportive spirit. Occasionally they perch on a thistle-top or low bush, but never on trees. Their only language is a long, low, plaintive whistle, heard usually on warm still days in winter.
112. TaeNIOPTERA NENGETA (Linn.).
(PEPOAZA TYRANT.)
+Taenioptera nengeta+, _Burm. La-Plata Reise_, ii. p. 459 (Parana); _Scl. et Salv. Nomencl._ p. 42; _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 137 (Entrerios); _White, P. Z. S._ 1882, p. 603 (Misiones).
_Description._--Above cinereous; lores white; wings black, coverts cinereous; a well-marked speculum at the base of the primaries and the edgings of the outer secondaries white; tail black, tipped with whitish cinereous, basal one-third of tail white; below pale cinereous, middle of throat white, with blackish stripe on each side; middle of belly, flanks, crissum, and under tail-coverts white; bill horn-colour; feet black: whole length 90 inches, wing 50, tail 35. _Female_ similar.
_Hab._ S.E. Brazil, Paraguay, Uruguay, Argentine Republic, and Bolivia.
To this species Azara gives the name of _Pepoaza_, the Guarani for Barred-wing; and _Pepoaza_ was used by him as a generic name for the small, well-defined group now placed in the genus _Taenioptera_, comprising eight known species. Most of these birds have some conspicuous wing-mark. They inhabit the southern portion of the South-American continent, from South Brazil and Bolivia to the Straits of Magellan, and are most numerous on the open pampas and in Patagonia.
In size they do not vary greatly, the largest being about nine inches long, the smallest about seven. In colour they are grey, or, more frequently, white relieved with black or grey, one species (_T.
rubetra_) being rufous. Their legs are long, and they run on the ground like _Myiotheretes rufiventris_, feeding, to some extent, in the same manner; but they also occasionally pursue and capture insects on the wing, like the typical Tyrant-birds that seldom or never alight on the ground. They have likewise another and unique preying-habit, intermediate between the Plover-like habits of _Agriornis_, _Myiotheretes_, and _Muscisaxicola_, and the Swallow- or Flycatcher-like habits of the true Tyrants. The bird perches itself on an elevation--the summit of a stalk, or bush, or even of a low tree--to watch like a Flycatcher for its insect prey; only instead of looking about for pa.s.sing insects, it gazes intently down at the ground, just as a Kingfisher does at the water, and when it spies a beetle or gra.s.shopper, darts down upon it, not, however, to s.n.a.t.c.h it up with the bill as other Tyrants do, but it first grasps it with its feet, then proceeds to despatch it, swaying about and opening its wings to keep its own balance, just as an Owl is seen to do when it grasps a mouse or other small animal in its claws. After devouring the insect on the spot, it flies back to its perch to resume the watch. They are very restless, active, playful birds, and seldom remain long on one spot, apparently finding it irksome to do so; but I have seen the _T. irupero_ occupy the same perch for hours every day while looking out for insects.
As an English generic name for this small interesting group might be useful, I would suggest _Ground-gazers_ or _Ground-watchers_, which describes the peculiar preying-habit of these birds.
The Pepoaza is a swift, active, graceful bird, with a strong, straight beak, hooked at the point, and a broad tail four inches long, the total length of the bird being nine inches. The throat and s.p.a.ce between the beak and eye are white; all the rest of the body, also the wing- and tail-coverts, light grey; tail and wing-quills black, with a pure white band across the base of the primaries. The tertiaries and rectrices are tipped with pale rufous grey.
It inhabits Brazil south of the equator, Bolivia and Paraguay, also the northern provinces of the Argentine Republic. Mr. Barrows gives the following account of its lively habits in Entrerios:--"They are commonly seen perched on fences or the tops of bushes or trees in open ground, frequently making sallies for winged insects, or dropping to the ground to catch a gra.s.shopper or worm. When shot at while perched and watching you, they almost invariably leave the perch at the flash, pitching forward and downward, and usually evading the shot, even at short range.
Several times I have secured them by shooting about a foot below and two feet in front of them as they sat, but they do not always fly in this direction. The rapidity of their flight when frightened, or when quarrelling, is simply astonis.h.i.+ng. I have seen one chase another for three or four minutes, doubling, turning, twisting, and shooting, now brus.h.i.+ng the gra.s.s, and now rising to a height of at least two or three hundred feet, and all the movements so rapid that the eye could scarcely follow them; and at the end of it each would go back to the top of his own chosen weed-stalk, apparently without a feather ruffled."
Azara found this species breeding in a hole in a bank; and Mr. Dalgleish has described a nest, taken from a tree in Uruguay, as a somewhat slight structure, four inches in diameter, formed of sticks and fibres, lined with fine gra.s.s and a few feathers. It contained three eggs, pear-shaped, white, with large well-defined spots of reddish brown.
113. TaeNIOPTERA CORONATA (Vieill.).
(BLACK-CROWNED TYRANT.)
+Taenioptera coronata+, _Burm. La-Plata Reise_, ii. p. 459; _Scl. et Salv. Nomencl._ p. 42; _Durnford, Ibis_, 1877, p. 176 (Buenos Ayres); _White, P. Z. S._ 1882, p. 603 (Buenos Ayres); _Doring, Exp. al Rio Negro, Zool._ p. 42 (R. Colorado); _Barrows, Bull. Nutt. Orn. Cl._ vol. viii. p. 138 (Entrerios). +Xolmis variegata+, _Darw. Zool. Voy. Beagle_, iii. p. 54 (Santa Fe).
_Description._--Above cinereous; rounded summit of head black, broad front and band encircling the black of the head white; wings blackish, upper coverts cinereous, edgings of middle and greater coverts and of outer secondaries whitish; tail blackish, margins of outer webs of external tail-feathers white; beneath white; under wing-coverts and a large portion of the inner webs of the remiges, except of the two outer primaries, white; bill and feet black; whole length 78 inches, wing 46, tail 31. _Female_ similar.
_Hab._ Argentine Republic, Uruguay, and Paraguay.
In this species the s.e.xes are alike. The crown is black and composed of loose feathers; the forehead, and a broad line over the eye which extends nearly round the head, also all the under plumage, pure white; neck and back clear grey; quills black.
This Tyrant is a solitary bird, though often many individuals are found within call of each other, and they sometimes even unite in a loose flock. It is found throughout the Argentine country, ranging south to the Rio Negro, in Patagonia, but abounds most on the Buenos-Ayrean pampas, where it performs a partial migration. Most of the _Taeniopterae_ seek their food by preference on the bare level ground, or where the vegetation is most scanty. This species varies somewhat in habits, and seldom runs on the ground, and chiefly inhabits the desert plains, where the large gra.s.ses flourish. On one occasion when I was with an expedition on the pampas for several weeks, every day a number of these birds would gather and follow us; perched here and there on the tall gra.s.ses with their bosoms toward us, they often looked at a distance like large white flowers. Old gauchos have told me that fifty years ago they were abundant all over the pampas, but have disappeared wherever the giant gra.s.ses have been eaten down, and have given place to a different vegetation.
Their note is a long, low whistle, the usual language of the _Taeniopterae_; but in this species it is very like a human whistle, on account of which the bird is named _Boyero_ (ox-driver) on the pampas.
One severe winter great numbers of them appeared in the neighbourhood of Buenos Ayres, and it was amusing to see the dogs thrown into a great state of excitement by the low whistling notes heard perpetually from all sides. Every few moments they would start up and stare about them to ascertain where the deceptive call came from, and in spite of many disappointments they would occasionally all rush away, loudly barking, into the plantation, convinced that some person there was whistling to call them.
The Black-Crown makes a somewhat shallow nest in a bush or large clump of gra.s.s, and lays four white eggs, with large dark red spots, chiefly at the big end.
I cannot refrain from quoting a pa.s.sage from Mr. Barrows's paper, descriptive of the lively temper and habits of this bird:--
"This species frequently persecutes smaller birds in a way which seems to imply pure love of mischief. One afternoon in July, when the river had fallen some feet after an unusual rise, I was walking along the lines of drift left by the falling water, and watching the different birds which were picking up insects or other food from the wind-rows.
A score or two of the little chestnut-backed _Centrites_ were running about, and here and there a _Taenioptera_ was looking quietly on.
Suddenly I heard a chirp of distress, and looking up saw one of these small birds apparently making every effort to escape from a _Taenioptera_, which was following in full chase. The two birds were hardly a length apart and both going at full speed, doubling and dodging in a way that would have done credit to a bat. The chase lasted perhaps for half a minute, when the smaller bird alighted, and at once the other also alighted and began running about unconcernedly and picking up food.
But the instant the smaller one made a start his enemy was at his heels (or more properly his tail) again, and he was forced to alight. This was repeated so often that I was on the point of shooting the pursuer, when, without any notice, he flew quietly off, and resumed his usual demeanour. It looked like a case of simple spite, for even if there were twenty other birds about, one seemed to be followed without regard to the rest."
I have often watched _Taeniopterae_ of different species, also _Myiotheretes rufiventris_ behaving in a similar way, and agree with Mr.
Barrows that it is "an _amus.e.m.e.nt_ in which the larger bird indulges simply for the pleasure derived from the exercise of his power."
114. TaeNIOPTERA DOMINICANA (Vieill.).
(DOMINICAN TYRANT.)
+Taenioptera dominicana+, _Burm. La-Plata Reise_, ii. p. 460 (Entrerios); _Scl. et Salv. Nomencl._ p. 42; _Durnford, Ibis_, 1877, p. 176 (Buenos Ayres); _White, P. Z. S._ 1883, p. 38 (Buenos Ayres); _Doring, Exp. al Rio Negro, Zool._ p. 42 (Azul, Currumalan); _Barrows, Bull. Nutt. Orn. Cl._ vol. viii. p. 139 (Entrerios, Pigue, Pampas).
_Description._--Above pure white; wings black, with a broad whitish subapical band across the first six primaries, beyond which the tips are blackish; tail black; beneath pure white: whole length 80 inches, wing 46, tail 42. _Female_ similar, but head above and back cinereous.
_Hab._ S.E. Brazil, Paraguay, Uruguay, and Argentine Republic.
This bird ranges from South Brazil and Paraguay to the southernmost pampas of Buenos Ayres. Its total length is eight inches. The wings and tail are black, the former barred with white; all the rest of the plumage in the male is pure white; in the female the upper parts are grey.
It is to some extent migratory, and usually goes in flocks of a dozen or twenty birds, and frequents open situations where there are bushes and trees, also plains covered with giant gra.s.ses. They are more social in their habits than _T. coronata_, but in other respects closely resemble it, and are exceedingly active lively birds, and when the flock is on the wing continually pursue each other in a playful manner.
Mr. Barrows observed them in autumn on the Pigue (southern pampas) preparing for their migration. "Late in March," he says, "we found them in large scattered flocks, which collected in one place toward evening, and went through a series of aerial evolutions accompanied with vocal exercises of a varied and entertaining kind, lasting half an hour or more.
"I presume this was in preparation for their northward (or westward?) migration, as we did not see them again after leaving this spot."