Argentine Ornithology - Volume I Part 20
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Volume I Part 20

_Hab._ Argentina, Paraguay, and E. Brazil.

The most interesting point concerning this species is the very great difference in habits, as well as appearance, existing between the s.e.xes.

In form it resembles the Starling of Europe, but is a trifle smaller and has a shorter tail. The male is black, the upper parts faintly mottled with yellowish grey; there is a straw-coloured stripe over the eye; the throat and breast bright crimson. The female is a smaller bird, and in colour dull fulvous grey, mottled with fuscous; the red tint on the breast scarcely perceptible.

These birds are migratory, and appear everywhere in the eastern part of the Argentine country early in October, arriving singly, after which each male takes up a position in a field or open s.p.a.ce abounding with coa.r.s.e gra.s.s and herbage, where he spends most of the time perched on the summit of a tall stalk or weed, his glowing crimson bosom showing at a distance like some splendid flower above the herbage. At intervals of two or three minutes he soars vertically up to a height of twenty or twenty-five yards to utter his song, composed of a single long, powerful, and rather musical note, ending with an attempt at a flourish, during which the bird flutters and turns about in the air; then, as if discouraged at his failure, he drops down, emitting harsh guttural chirps, to resume his stand. Meanwhile, the female is invisible, keeping closely concealed under the long gra.s.s. But at length, attracted perhaps by the bright bosom and aerial music of the male, she occasionally exhibits herself for a few moments, starting up with a wild, zigzag flight, like a Snipe flushed from its marsh, and, darting this way and that, presently drops into the gra.s.s once more. The moment she appears above the gra.s.s the male gives chase, and they vanish from sight together. Thus, while in colour, habits, language, and even in its manner of soaring up like a rocket to let off its curious melody, the male is the most conspicuous of small birds, the female, acted on in an opposite direction by natural selection, has been, so to speak, effaced.

While flying, they do not look like birds of the same species: the male moves with wings rapidly fluttered, like a Starling, but with a slower, more laborious flight, and without deviating; the female, in her eccentric movements in the air, reminds one of a large moth driven from its hiding-place, and flying about confused with the glare of noon.

The nest is made of dry gra.s.s on the ground, so cunningly concealed that it is most difficult to find. The eggs are four, white, spotted with reddish brown. When they have young, I have never been able to detect the female flying about in search of food.

All through the summer these birds are solitary, but when migrating in the autumn, though many are seen travelling singly, and appear very conspicuous as they fly laboriously in a straight line, at an alt.i.tude of about twenty yards from the surface, others are seen making their journey in small flocks or parties composed of six to a dozen individuals. These are the males. The females travel separately, in twos or threes or singly, flying nearer to the earth, with frequent pauses, when the wings cease beating, and intervals of gliding, also darting occasionally to one side, as if the bird had suddenly taken fright.

101. AMBLYRHAMPHUS HOLOSERICEUS (Scop.).

(SCARLET-HEADED MARSH-BIRD.)

+Amblyrhamphus holosericeus+, _Hudson, P. Z. S._ 1870, p. 114 (Buenos Ayres); _Scl. et Salv. Nomencl._ p. 37; _Durnford, Ibis_, 1877, p. 174 (Buenos Ayres); _Gibson, Ibis_, 1880, p. 18 (Buenos Ayres); _White, P. Z. S._ 1882, p. 602 (Buenos Ayres); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 135 (Entrerios); _Scl. Cat. B._ xi. p. 351. +Amblyrhamphus ruber+, _Burm. La-Plata Reise_, ii. p.

491 (Entrerios, Santa Fe, Parana).

_Description._--Black; whole head and neck all round, and upper breast and thighs scarlet; bill and feet black: total length 95 inches, wing 45, tail 40. _Female_ similar. _Young_ uniform black.

_Hab._ Paraguay, Uruguay, and Argentina.

Azara named this species _Tordo negro cabeza roxa_; it is also called _Boyero_ (ox-herd) by country people, from its note resembling the long whistle of a drover; and sometimes _Chisel-bill_, from the peculiar conformation of the beak, which is long, straight, and has a broad fine point like a chisel. In both s.e.xes the plumage of the head and neck is scarlet, of an exceedingly brilliant tint, all other parts intense black. These birds are lively, active, and sociable, going in flocks of from half-a-dozen to thirty individuals; they remain all the year, and inhabit the marshes, from which they seldom wander very far, but seek their insect food in the soft decaying rushes. They are common on the swampy sh.o.r.es of the Plata, and when seen at a distance, perched in their usual manner on the summits of the tall rushes, their flame-coloured heads shine with a strange glory above the sere sombre vegetation of the marshes. The long whistling note above mentioned is their only song, but it varies considerably, and often sounds as mellow and sweet as the whistle of the European Blackbird.

The nest is an ingenious structure of dry gra.s.ses, fastened to the upright stems of an aquatic plant, three or four feet above the water.

The eggs are four, in size and form like those of the English Song-Thrush, spotted somewhat spa.r.s.ely with black on a light blue ground.

The young birds are entirely black at first, and afterwards a.s.sume on the head and neck a pale terra-cotta red, which gradually deepens to vivid scarlet.

102. PSEUDOLEISTES VIRESCENS (Vieill.).

(YELLOW-BREASTED MARSH-BIRD.)

+Pseudoleistes virescens+, _Hudson, P. Z. S._ 1870, p. 549, et 1874, p. 156 (Buenos Ayres); _Scl. et Salv. Nomencl._ p. 37; _Durnford, Ibis_, 1877, p. 175, et 1878, p. 59 (Buenos Ayres); _Gibson, Ibis_, 1880, p. 31 (Buenos Ayres); _White, P. Z. S._ 1882, p. 602 (Buenos Ayres); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 135 (Entrerios); _Scl. Cat. B._ xi. p. 352. +Leistes anticus+, _Burm.

La-Plata Reise_, ii. p. 491 (Parana).

_Description._--Above and below dark olive-brown; lesser upper wing-coverts, under wing-coverts, and middle of the abdomen yellow; bill black; feet dark brown: total length 95 inches, wing 46, tail 38. _Female_ similar.

_Hab._ S. Brazil, Paraguay, Uruguay, and Argentina.

In both s.e.xes in this species the plumage is deep olivaceous brown, the breast pure yellow. It is active, strong on the wing, sociable and noisy; and being moreover a pretty and elegant bird, very common in settled districts, and with a preference for man's neighbourhood, it is familiar to every one, and has won amongst many compet.i.tors the vernacular name of _Pecho-amarillo_ (Yellow-breast), for with us yellow-breasted species are somewhat numerous. It remains all the year, invariably going about in flocks of from twenty to thirty birds, and feeds on the ground in the fields or on the open plain. While they are feeding, one bird takes up a position on a stalk or thistle-top to keep guard; when he flies down another bird takes his place; if a person approaches, the sentinel gives the alarm, and all the birds fly off in a very close flock, making the air resound with their loud ringing notes.

After feeding, they repair to the trees, where they join their robust voices in a spirited concert, without any set form of melody such as other song-birds possess, but all together, flinging out their notes at random, as if mad with joy. In this delightful hubbub there are some soft silvery sounds. Where they are never persecuted they have little fear of man, but they invariably greet his approach with a loud vigorous remonstrance.

In October the birds break up their companies to pair. Sometimes they breed on the open plain in a large cardoon thistle, but a thick bush or low tree is preferred. The nest is like that of a Thrush, being deep, compactly made of dry gra.s.s and slender sticks, plastered inside with mud, and lined with hair or soft dry gra.s.s. It is, however, deeper and more symmetrical than the Thrush's nest, and it is sometimes plastered with cow-dung instead of with mud. The eggs are four, very long, white, and abundantly spotted with deep red, the spots becoming confluent at the large end.

The Yellow-breast is never seen to quarrel with its fellows or with other birds, and it is possibly due to its peaceful disposition that it is more victimized by the parasitical _Molothrus_ than any other bird. I have frequently found their nests full of parasitical eggs, as many as fourteen and in one case sixteen, eggs in one nest. In some seasons all the nests I found and watched were eventually abandoned by the birds on account of the number of parasitical eggs dropped in them. I have also so frequently found parasitical eggs on the ground under the nest that I believe the Yellow-breast throws out some of these foreign eggs, and in one instance I was quite sure that this had happened. The nest was in a cardoon bush, and contained five eggs--two of the Yellow-breast and three parasitical. These three were of the variety most thickly mottled with red, and consequently closely resembling the eggs of the Yellow-breast. I was surprised to find five more eggs of the Cow-bird on the ground, close together, and about three feet from the bush; and these five eggs were all pure white and unspotted. Naturally I asked, How came these eggs in such a position? They had not fallen from the nest, which was very deep, contained few eggs, and was scarcely thirty inches above the ground. Then they were all white, while those in the nest were mottled. That the eggs had been laid in the nest I felt certain; and the only way I can account for their being in the place where I found them is that the Yellow-breast itself removed them, taking them up in its bill and flying with them to the ground. If I am right, we must believe that this individual Yellow-breast had developed an instinct unusual in the species, which enables it to distinguish, and cast out of its nest, eggs very different from its own--an instinct, in fact, the object of which would be to counteract the parasitical habit of _Molothrus_. What would be the effect of such an instinct should the species acquire it? Doubtless it would be highly prejudicial to the parasitical birds laying white eggs, but favourable to those laying mottled eggs. This would be natural selection operating in a very unusual manner; for the Yellow-breast, or other species, would improve another to its own detriment, since the more the parasitical eggs a.s.similated to its own, the greater would be the likelihood of their being preserved. The perfect similarity of the eggs of _M.

rufoaxillaris_ to those of _M. badius_ perhaps was brought about in this way. But, it may be added, if besides the Yellow-breast some one other species laying very different eggs (a _Zonotrichia_ or _Tyrannus_, for instance) should also acquire this distinguishing habit, and eject all eggs unlike its own from its nest, the habit in the two or more species would ultimately cause the extinction of the parasite.

It might throw some light on this obscure subject to examine, for several successive summers, a large number of nests, to ascertain whether the nests of the Yellow-breast are often found without any white unspotted eggs, or if the same proportional number of white (parasitical) eggs are found in the nests of the Yellow-breast, Scissor-tail, Song-Sparrow, Pipit, and other species.

103. TRUPIALIS MILITARIS (Linn.).

(PATAGONIAN MARSH-STARLING.)

+Sturnella militaris+, _Hudson, P. Z. S._ 1872, p. 548 (Rio Negro); _Scl. et Salv. Nomencl._ p. 38; _Durnford, Ibis_, 1877, p. 33, et 1878, p. 394 (Chupat). +Sturnella loica+, _Doring, Exp. al Rio Negro, Zool._ p. 41 (R. Colorado, R. Negro). +Trupialis militaris+, _Scl. Cat. B._ xi. p. 356. +Trupialis loyca+, _Burm.

La-Plata Reise_, ii. p. 491 (Mendoza).

_Description._--Above brown, especially on the head and back variegated with black; superciliaries in front of the eye red, behind the eye white; beneath black; throat, middle of the neck, breast, and upper belly scarlet; sides of belly and crissum with brownish edgings to the black feathers; under wing-coverts white; bend of the wing red; slight rictal stripe white; bill horn-colour; feet brown: total length 100 inches, wing 47, tail 36. _Female_ similar.

_Hab._ Chili, Patagonia, and Falkland Islands.

Two species of _Trupialis_ inhabit the southernmost part of the Argentine Republic, the present being confined to Patagonia and South Chili, while its northern representative inhabits the pampas of Buenos Ayres and Uruguay. Probably the Colorado River, which separates two districts differing in soil and vegetation, is the boundary-line dividing their habitats. So nearly alike are these two birds in colour, language, and habits, that they seem rather like races than species; and they were so regarded by naturalists until recently, when the pampas bird was raised to the rank of a distinct species, with the name of _Trupialis defilippii_. Unfortunately the old name _militaris_ fits the Pampas, and not the Patagonian, Starling best; but of this I shall speak when I describe the former species.

In form and size _T. militaris_ resembles the Common Starling of Europe, but differs from it in habits, flight, language, and in colouring; its upper plumage being fuscous mottled with yellowish grey, the throat and bosom scarlet inclining to crimson. This hue varies greatly, the breast-feathers being often tipped with white, which subdues the intense red, and gives it a rosy tint in some individuals. The female is paler-plumaged than the male, and has less red on the breast.

It inhabits the whole of Patagonia to the Strait of Magellan, but is confined to the valleys or to the neighbourhood of water; and Durnford remarks that it is a useful bird to the traveller in that thirsty country, as its presence is a sure indication of water. It is resident, and is seen in small parties of four or five, or in small flocks seldom exceeding twenty or thirty in number. It feeds and lives on the ground, and only occasionally is it seen to perch on a low bush. Its flight is strong, and it flies about a great deal, and usually utters its song when on the wing. The song is continued all the year, and is heard even on the coldest days in winter; the notes are few and not highly melodious, but are cheerful and vigorous.

The nest is made of dry gra.s.s and rootlets attached to the rushes in moist ground, and placed close to or resting on the surface. The eggs are five, the ground-colour white spotted or blotched with reddish brown.

104. TRUPIALIS DEFILIPPII, Bp.

(DE FILIPPI'S MARSH-STARLING.)

+Sturnella defilippii+, _Scl. et Salv. P. Z. S._ 1869, p. 161 (Buenos Ayres); _iid. Nomencl._ p. 38; _Doring, Exp. al Rio Negro, Zool._ p. 41 (Pampas); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 136 (Pampas south of Buenos Ayres). +Trupialis defilippii+, _Scl.

Cat. B._ xi. p. 357. +Trupialis militaris+, _Burm. La-Plata Reise_, ii. p. 490 (Rosario, Parana).

_Description._--Like _Tr. militaris_, but rather smaller, and with the under wing-coverts black.

_Hab._ Northern Argentina and Uruguay.

Throughout the country where this species abounds it is called _Pecho colorado_, which is certainly better than Azara's barbarous, if picturesque, name of _Degollado_; but no happier name than _militaris_ could have been invented for it, by which it was formerly known to naturalists; and though it was given to the bird merely on account of the red breast, and was therefore equally applicable to all the red-breasted species on the globe, in this case it accidentally seemed to describe a peculiar habit of the bird, as well as its bright livery.

In size, form, gait, flight, language, and colour the present bird very closely resembles the Patagonian Starling; but the crimson on the breast is brighter and the upper parts are darker. Its nesting-habits are also like those of the southern bird; the number and colour of the eggs being the same in both species. One trivial difference in habit is that De Filippi's Starling occasionally soars up a few yards into the air when uttering its song. It inhabits the moist gra.s.sy pampas in the southern part of the Buenos Ayrean province, and is there abundant and unites in large flocks. At the approach of the cold season there is a general movement northwards of the birds, which does not, however, extend far, as the birds, although strong fliers, travel slowly and in a peculiar manner; it is in this season, when the birds are seen moving in large flocks, that the name of Military Starling strikes one as being peculiarly appropriate. They do not journey through the air like other migrants, but move over the ground, when the flock, composed of four or five hundred to a thousand or more individuals, is extended so as to present a very long front, and at intervals the hindmost birds fly over the others and alight just in advance of them: the long front, the precision of their movements, and their scarlet bosoms all turned one way, suggest the idea of a disciplined army on its march.

They never perch on trees, but frequently alight on the roof of a rancho or other elevation affording a secure footing. They are tame birds and fly reluctantly; when approached, they usually crouch down, hiding their crimson bosoms, and remain motionless in order to escape observation.

In disposition they are peaceful, and so fond of society that when one becomes separated from his fellows he will unite with birds of another kind, even with Plovers or Tyrant-birds.

On the great monotonous plains, where most of the small birds are grey- or brown-plumaged, and in winter when there are no flowers to satisfy the desire of the eye for bright colour, it is delightful, while travelling, to meet with an army of these Starlings: their crimson bosoms, less bright than the hues of some tropical species, seem then to glow with a strange splendour on the sombre green of earth, and the sight produces an exhilarating effect on the mind.

105. ICTERUS PYRRHOPTERUS, Vieill.

(CHESTNUT-SHOULDERED HANG-NEST.)

+Icterus pyrrhopterus+, _Scl. et Salv. P. Z. S._ 1868, p. 140; _iid.