Chapter XX: Nothura Darwini 213 (11)

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 cock-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 cock 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 assiduously tended and watched over by the cock, 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 36·0 inches,
tarsus 11·0; tarsus partly feathered.

_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 "Molú Chueké"--short or dwarf Chueké; 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 noble 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 assimilates. 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 shell 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 assumes 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 shell. 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.