Argentine Ornithology - Volume Ii Part 42
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Volume Ii Part 42

The call-note of the Martineta is never heard in winter; but in the month of September they begin to utter in the evening a long, plaintive, slightly modulated whistle, the birds sitting concealed and answering each other from bush to bush. As the season advances the coveys break up, and their call is then heard on every side, and often all day long, from dawn until after dark. The call varies greatly in different birds, from a single whistle to a performance of five or six notes, resembling that of _Rhynchotus_, but inferior in compa.s.s and sweetness. They begin to breed in October, making the nest in the midst of a small isolated bush. The eggs vary in number from twelve to sixteen; they are elliptical in form, of a beautiful deep green in colour, and have highly polished sh.e.l.ls.

It is probable, I think, that this species possesses some curious procreant habits, and that more than one female lays in each nest; but owing to the excessive wariness of the bird in a state of nature it is next to impossible to find out anything about it. No doubt the day will come when naturalists will find the advantage of domesticating the birds the life-histories of which they wish to learn: may it come before all the most interesting species on the globe are extinct!

Order XX. STRUTHIONES.

Fam. LIV. RHEIDae, or RHEAS.

The Order of Struthious Birds or Ostriches is represented in South America by the Nandu or Rhea, which is at once distinguished from the African Ostrich (_Struthio_) by having three toes instead of two, as also by many other important points of structure.

Both the known species of _Rhea_ are found within our limits.

433. RHEA AMERICANA, Lath.

(COMMON RHEA.)

+Rhea americana+, _Darwin, Zool. Voy. 'Beagle,'_ iii. p. 120; _Burm.

La-Plata Reise_, ii. p. 500; _Scl. et Salv. Nomencl._ p. 154; _Sclater, Trans. Zool. Soc._ iv. p. 355, pl. lxviii.; _Gadow, P.

Z. S._ 1885, p. 308.

_Description._--Above, head blackish; neck whitish, becoming black at the base of the neck and between the shoulders; rest slaty grey: beneath, throat and upper neck whitish, becoming black at the base of the neck, whence arise two black lateral crescents, one on either side of the upper breast; rest of under surface whitish; front of tarsus throughout covered with broad transverse scutes: whole length about 520 inches, tarsus 120; tarsus bare.

[Ill.u.s.tration: Head of _Rhea americana_. (P. Z. S. 1860, p. 208.)]

_Hab._ Pampas of S. America north of Rio Negro.

The Common Rhea (called "_nandu_" in the Guarani language, "_Chueke_" by the pampas Indians, and "Ostrich" by Europeans) is found throughout the Argentine Republic down to the Rio Negro in Patagonia, and, in decreasing numbers, and a.s.sociating with Darwin's Rhea, to a considerable distance south of that river. Until within very recent times it was very abundant on the pampas, and I can remember the time when it was common within forty miles of Buenos Ayres city. But it is now becoming rare, and those who wish to have a hand in its extermination must go to a distance of three or four hundred miles from the Argentine capital before they can get a sight of it.

The Rhea is peculiarly well adapted, in its size, colour, faculties, and habits, to the conditions of the level woodless country it inhabits; its lofty stature, which greatly exceeded that of any of its enemies before the appearance of the European mounted hunter, enables it to see far; its dim grey plumage, the colour of the haze, made it almost invisible to the eye at a distance, the long neck being so slender and the bulky body so nearly on a level with the tall gra.s.ses; while its speed exceeded that of all other animals inhabiting the same country. When watching the chase of Ostriches in the desert pampas, abounding in giant gra.s.ses, it struck me forcibly that this manner of hunting the bird on horseback had brought to light a fault in the Rhea--a point in which the correspondence between the animal and its environment is not perfect.

The Rhea runs smoothly on the surface, and where the tall gra.s.s-tussocks are bound together, as is often the case, with slender twining plants, its legs occasionally get entangled, and the bird falls prostrate, and before it can struggle up again the hunter is close at hand and able to throw the _bolas_--the thong and b.a.l.l.s, which, striking the bird with great force, wind about its neck, wings, and legs, and prevent its escape. When I questioned Ostrich-hunters as to this point they said that it was true that the Rhea often falls when running hotly pursued through long gra.s.s, and that the deer (_Cervus campestris_) never falls because it leaps over the large tussocks and all such obstructions. This small infirmity of the Rhea would not, however, have told very much against it if some moderation had been observed in hunting it, or if the Argentine Government had thought fit to protect it; but in La Plata, as in North America and South Africa, the licence to kill, which every one possesses, has been exercised with such zeal and fury that in a very few more years this n.o.blest Avian type of the great bird-continent will be as unknown on the earth as the Moa and the _aepyornis_.

The Rhea lives in bands of from three or four to twenty or thirty individuals. Where they are not persecuted they show no fear of man, and come about the houses, and are as familiar and tame as domestic animals.

Sometimes they become too familiar. At one _estancia_ I remember an old c.o.c.k-bird that constantly came alone to feed near the gate, and that had so great an animosity against the human figure in petticoats, that the women of the house could not go out on foot or horseback without a man to defend them from its attacks. When the young are taken from the parent bird they become, as Azara truly says, "domestic from the first day," and will follow their owner about like a dog. It is this natural tameness, together with the majesty and quaint grace of its antique form, which makes the destruction of the Rhea so painful to think of.

When persecuted, Rheas soon acquire a wary habit, and escape by running almost before the enemy has caught a sight of them; or else crouch down to conceal themselves in the long gra.s.s; and it then becomes difficult to find them, as they lie close, and will not rise until almost trodden on. Their speed and endurance are so great that, with a fair start, it is almost impossible for the hunter to overtake them, however well mounted. When running, the wings hang down like those of a wounded bird, but usually one wing is raised and held up like a great sail, for what reason it is impossible to say. When hard pressed, the Rhea doubles frequently and rapidly at right angles to its course; and if the pursuer's horse is not well trained to follow the bird in all its sudden turns without losing ground he is quickly left far behind.

In the month of July the love-season begins, and it is then that the curious ventriloquial bellowing, booming, and wind-like sounds are emitted by the male. The young males in the flock are attacked and driven off by the old c.o.c.k-bird; and when there are two old males they fight for the hens. Their battles are conducted in a rather curious manner, the combatants twisting their long necks together like a couple of serpents, and then viciously biting at each other's heads with their beaks; meanwhile, they turn round and round in a circle, pounding the earth with their feet, so that where the soil is wet or soft they make a circular trench where they tread. The females of a flock all lay together in a natural depression in the ground, with nothing to shelter it from sight, each hen laying a dozen or more eggs. It is common to find from thirty to sixty eggs in a nest, but sometimes a larger number, and I have heard of a nest being found containing one hundred and twenty eggs. If the females are many the c.o.c.k usually becomes broody before they finish laying, and he then drives them with great fury away and begins to incubate. The hens then drop their eggs about on the plains; and from the large number of wasted eggs found it seems probable that more are dropped out of than in the nest. The egg when fresh is of a fine golden yellow, but this colour grows paler from day to day, and finally fades to a parchment-white.

After hatching, the young are a.s.siduously tended and watched over by the c.o.c.k, and it is then dangerous to approach the Rhea on horseback, as the bird with neck stretched out horizontally and outspread wings charges suddenly, making so huge and grotesque a figure that the tamest horse becomes ungovernable with terror.

Eagles and the large Polyborus are the enemies the Rhea most fears when the young are still small, and at the sight of one flying overhead he crouches down and utters a loud snorting cry, whereupon the scattered young birds run in the greatest terror to shelter themselves under his wings.

434. RHEA DARWINI, Gould.

(DARWIN'S RHEA.)

+Rhea darwini+, _Darwin, Zool. Voy. 'Beagle,'_ iii. p. 123, pl.

xlvii.; _Hudson, P. Z. S._ 1872, p. 534; _Sclater, Trans. Zool.

Soc._ iv. p. 357, pl. lxx.; _Gadow, P. Z. S._ 1885, p. 308.

+Pterocnemis darwini+, _Scl. et Salv. Nomencl._ p. 154.

_Description._--Above red or buff-brown, most of the feathers of the back with white shaft-stripes and wide white margins: beneath, throat and neck buff-brown; rest of under surface whitish; front of tarsus covered on the upper part by small reticulate scutes, on the lower part by transverse scutes: whole length about 360 inches, tarsus 110; tarsus partly feathered.

[Ill.u.s.tration: Head of _Rhea darwini_. (P. Z. S. 1860, p. 209.)]

_Hab._ Patagonia south of the Rio Negro.

Darwin's Rhea inhabits Patagonia from the Straits of Magellan to the Rio Negro, and is also met with occasionally north of that river. The Indians call it "Molu Chueke"--short or dwarf Chueke; its Spanish name is "_Avestruz petizo_." They were formerly very abundant along the Rio Negro; unhappily, some years ago their feathers commanded a very high price; Gauchos and Indians found that hunting the Ostrich was their most lucrative employment; consequently these n.o.ble birds were slaughtered in such numbers that they have been almost exterminated wherever the nature of the country admits of their being chased. When on the Rio Negro in 1871 I was so anxious to obtain specimens of this Rhea that I engaged several Indians by the offer of a liberal reward to hunt for me, but they failed to capture a single adult bird. I can only set down here the most interesting facts I was able to collect concerning its habits, which are very imperfectly known.

When pursued it frequently attempts to elude the sight by suddenly squatting down amongst the bushes, which have a grey foliage, to which the colour of its plumage closely a.s.similates. When hard pressed it possesses the same habit as the Common Rhea of raising the wings alternately and holding them up vertically; and also doubles suddenly like that species. Its speed is greater than that of the Common Rhea, but it is sooner exhausted. In running it carries its neck stretched forward almost horizontally, which makes it seem lower in stature than the allied species,--hence the vernacular name of "short Ostrich." It is found in flocks of from three or four to thirty or more individuals.

It begins to lay at the end of July, that is a month before the _Rhea americana_. Several females lay in one nest, which is merely a slight depression lined with a little dry rubbish; as many as fifty eggs are sometimes found in one nest. A great many wasted or _huacho_ eggs, as they are called, are also found at a distance from the nest. I examined a number of eggs brought in by the hunters, and found them vary greatly in shape, size, and colour. The average size of the eggs was the same as those of the Common Rhea; in shape they were more or less elliptical, scarcely any two being precisely alike. The sh.e.l.l has a fine polish, and when newly laid the colour is deep rich green. They soon fade, however, and the side exposed to the sun first a.s.sumes a dull mottled green; then this colour fades to yellowish, and again to pale stone-blue, becoming at last almost white. The comparative age of each egg in the nest may be known by the colour of the sh.e.l.l. The male incubates and rears the young; and the procreant habits seem altogether like those of _Rhea americana_.

The young are hatched with the legs feathered to the toes; these leg-feathers are not shed, but are gradually worn off as the bird grows old by continual friction against the stiff scrubby vegetation. In adults usually a few scattered feathers remain, often worn down to mere stumps; but the hunters told me that old birds are sometimes taken with the legs entirely feathered, and that these birds frequent plains where there is very little scrub. The plumage of the young is dusky grey, without white and black feathers. When a year old they acquire by moulting the mottled plumage of the adults, but do not attain their full size until the third year.

APPENDIX.

I. _List of the princ.i.p.al Authorities upon the Ornithology of the Argentine Republic referred to in the present Work._

AZARA, DON FELIX DE.

Apuntamientos para la historia natural de los paxaros del Paraguay y Rio de la Plata. 3 vols. Madrid, 1802.

Although this celebrated work relates mainly to the neighbouring State of Paraguay, so many birds are common to Paraguay and La Plata that it has of course a most important bearing on the Ornithology of the latter country. Azara, unfortunately, gave only Spanish names to his birds, so that the Latin t.i.tles of them are mostly those of Vieillot, who translated Azara's remarks and gave scientific names to his birds in different volumes of the 'Nouveau Dictionnaire d'Histoire Naturelle'

(Paris, 1816-19). A most useful Index to Azara's 'Apuntamientos' was published in 1847 by Dr. G. Hartlaub of Bremen[11]. A more modern _resume_ of the Birds of Paraguay, in which much information is contained, has been recently written by Hans, Graf v. Berlepsch[12].

[11] Systematischer Index zu Don Felix de Azara's Apuntamientos para la historia natural de los paxaros del Paraguay y Rio de la Plata.

Bremen, 1847.

[12] Journ. f. Orn. 1887, p. 1.

BARROWS, WALTER B.

Birds of the Lower Uruguay. Bulletin of the Nuttall Ornithological Club, vol. viii. pp. 82, 128, 198; and The Auk, 1884, pp. 20, 109, 270, and 313.

This excellent observer was resident at Concepcion del Uruguay in 1879 and 1880, and afterwards made an excursion from Buenos Ayres southwards to the Sierra de la Ventana. His notes, many of which are incorporated in the present work, relate to about 200 species.

BURMEISTER, Dr. HERMANN.