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THE LIFE OF THE AFRICAN OSTRICH
BY WILLIAM CHARLES SCULLY
THERE has been some desultory controversy as to whether Africa contains only one species of ostrich or several species. In Mr. W. L. Sclater's Fauna of South Africa, four are mentioned, namely: Struthio camelus, which ranges over North Africa and Arabia, and in ancient times was found in Southwestern Asia; S. masaicus, S. molybdophanes, and S. australis. In view, however, of Professor Deurden's recent researches, it is fairly clear that this classification will have to be revised. Possibly there exists only one species, which includes several varieties. The ostrich is only semi-gregarious and, like all animals not wholly gregarious, is subject to individual variation. It is, however, stated that the Somaliland ostrich has a horny shield on the top of its head. If this be so, and especially if the horn be an excrescence from the skull, not only will S. molybdophanes establish its claim to being a separate species, but an interesting link between the ostriches and the cassowaries will be suggested.
The genus Struthio belongs to the subclass Ratitae, all the genera of which are flightless birds with no keel to the sternum or breast-bone. Such are the rheas, the cassowaries, the emus, and the kiwis. Except the ostrich, none of the genera of this subclass are found north of the equator. Up to a comparatively recent period, the ostrich ranged over the whole African continent except in the denser for
ests and on the higher mountain ranges.
Half a century ago the ostrich of Southern Africa was in danger of extinction; now, however, owing to domestication, its numbers have enormously increased. In 1913 there were 776,268 ostriches owned by farmers within the South African Union. Salutary laws for the protection of wild birds have also been enacted. Although wild birds have disappeared from the more settled parts, they are still to be found in considerable numbers in the less accessible areas, such as the Kalihari and Great Bushmanland deserts.
Very little is known of the habits of the wild birds; nearly every extant account bristles with inaccuracies. Some of the latter have their origin in the Bible, wherein, among other errors, it is stated that the eggs of the ostrich are hatched out by the heat of the sun, and that the young are cruelly deserted by their parents. In Job and Jeremiah the ostrich, which is really an example to many other birds in the matter of caring for its young, is held up to the execration of mankind as a cruel and unfeeling parent.
The male ostrich stands nearly eight feet high; the female about eighteen inches less. The upper portion of the body of the male, as well as the lower fourth of the neck, is covered with short, glossy black feathers. The foamwhite plumes are the primary feathers of the wings; plumes of an inferior quality form the tail. The hue of the female is a dove-tinted brown. Her
plumes are not nearly so luxuriant as those of the male, and are dingy-white in color. A full-grown male ostrich at the beginning of the breeding-season is a truly magnificent creature. The short, black feathers with which his back and sides are densely covered ripple and glint in the sunshine; his waving plumes gleam gallantly. So charged is he with abounding vigor that the blood suffuses the scales of the tarsi and the feet, the visible portion of the so-called thigh, the head and the beak, until they glow in clear crimson. His large, brilliant hazel eye flashes from beneath a fringe of black bristles. Fierce, fearless, and majestic, he stalks toward an intruder, lashing and whisking his plumes, hissing loudly, and snapping his beak. The strength of the ostrich is prodigious; he can disembowel a horse or kick through a sheet of corrugated iron. To an unprotected man in the open an infuriated ostrich is as dangerous as the lion. Many have lost their lives through ignorance of his strength, his speed, and his implacable ferocity.
Equally impressive is the demeanor of the male when wooing his mate. Here is the description given by Mr. Cronwright-Schreiner:
'A cock, if courting the hen, will often run slowly and daintily on the points of his toes, with neck slightly inflated, upright and rigid; the tail half-drooped and all his body-feathers fluffed up; the wings raised and expanded, the inside edges touching the neck for nearly the whole of its length, and the plumes showing separately, like an open fan, flat to the front, on each side of the head. In no other attitude is the splendid beauty of his plumage displayed to such advantage.'
The breast of the ostrich is oval, and bare of feathers. So strong is the sternum that it might almost be compared to the ram of a battleship except
that it is not beaked. portion consists of a bony shield which is heavily strutted by the ribs, and is but scantily covered with flesh. When the bird runs against any obstacle, or falls to the ground in its flight, it is the breast-bone which sustains the impact. When the cocks fight, as they often do, it is on this useful shield that the thundering kicks are usually received.
The wings have lost almost every vestige suggestive of their original function. Contrary to general opinion, they are of no use toward accelerating the speed of the bird when it runs; if anything they are a hindrance - especially if the bird be hard pressed. But they are serviceable in covering the eggs during the process of incubation, and also in enabling the bird to turn at a sharp angle in the course of a rapid run, or even to stop almost abruptly. In the process of 'waltzing' or gyrating, which will presently be described, the wings enable the bird to retain or recover its balance. But the true use of the wings lies in the transcendent beauty of the primary feathers. These were developed through sexual selection, by that influence which ever strives to lead the Caliban of passion from the morass to the mountain peak.
Incidentally, it is due to the beauty of its plumes that the ostrich has not become practically extinct in Southern Africa. Among the many animals which man has taken from their natural environment and adapted to his needs, the ostrich is the only one in respect of which sheer loveliness, as distinguished from utility, in its usually restricted sense,-formed the motive of domestication. It is also the only one which has benefited by the change. The ox, the horse, and the sheep have been reduced to a servitude of which many of the aspects are cruel. They all subserve material needs. But the ostrich furnishes plumes
which are probably the most perfect decorative items in Nature's storehouse, and, fortunately for itself, is otherwise of no use to man. It is kindly treated; even the removal of the feathers is quite a painless process. All this may be not without significance in the general scheme of things. As Emerson sang of the Rhodora, 'Beauty is its own excuse for being'; and in the estimation of a deeper civilization, a humming-bird flashing through sunlit greenery may be of far more importance than a fat bullock in the abattoir.
In the leg of the ostrich occurs most marvelous specialization. The bird has but two toes, the third and the fourth, the outer being somewhat short. The toes have springy pads beneath and are armed with strong nails. From the foot the tarsus rises for about eighteen inches; it is covered with wide transverse scales. Above the tarsus is the so-called thigh, which is really the tibia, or shin. Here the bone is swathed in huge muscles which are covered with naked skin- usually dark blue in color in the adult bird.
Dr. Haughton, in Volume IX of the Proceedings of the Royal Irish Academy, gave an excellent description of the ostrich's mode of running: 'In the act of running the leg of the ostrich is to be regarded as a jointed lever having four joints, viz., the hip, the knee, the heel, and the metatarsal joints. As the animal springs from foot to foot, the whole limb on reaching the ground is bent as far as possible at each of the articulations, and when the spring is made, the muscles proper to each joint increase the angle made by the bones meeting at the joint, so that the effect of the whole is to unbend the limb, and give it a maximum of extension at the moment of leaving the ground. During the spring the antagonist muscles again bend the joints, so that on next touching they are at their maximum
of flexion, again waiting to be unbent by the muscles that open the angles of the joints; and so on. As the animal runs, it is thrown alternately from each foot in contact with the ground, as from a catapult, and advances by successive leaps or springs from foot to foot.'
The speed thus attained is very great. For a comparatively short dis- • tance when the sun is hot, or for a practically unlimited distance if the day be cool, an adult ostrich can easily outspeed a horse. In running the bird holds its head somewhat low, with the neck flexed. Strangely enough, although the neck moves with slight undulations, the head remains steady. One peculiarity which does not appear to have been noted by other observers is this: if an ostrich be kept moving continuously on a very hot day, it will suddenly fall, roll over on its back, and die apparently of heat-apoplexy.
Sight is the special sense of the ostrich; the sense of hearing being next in importance. The sense of smell is, I am convinced, of use only in connection with feeding and in the matter of recognition of the young. I have several times had wild ostriches pass within a few hundred yards to leeward of where I lay concealed, without evincing the slightest alarm. The nostrils are narrow and lie in a membranous groove rather forward on the bill. The brain is exceedingly small; its weight has been computed to be in the proportion of 1 to 1200 as compared with the whole body. The brain of the eagle is about 1 to 150; that of the parroquet as 1 to 45. If one deducts from the ostrich's brain those portions specialized for sight and hearing, the remainder is almost infinitesimal. It has been related that Heliogabalus caused the brains of six hundred ostriches to be used for a single dish. Yet the ostrich is by no means a stupid creature.
Most of the older observers mention having seen ostriches herding with the larger wild animals, such as the zebra and the gnu. From my own observations, especially in connection with the hartebeest, I am convinced that it is the other animals which seek the society of the ostrich for the purpose of being insured against surprise. The commanding height and matchless eyesight of these birds give them a range of vision probably unsurpassed by any other flightless animal — except, possibly, the giraffe. In this connection it is interesting to note that in the first book of the Anabasis, Xenophon mentions the circumstance of ostriches and wild asses associating together on the plains to westward of the Euphrates.
Although it is usually the high, open desert plains that the ostrich frequents, it is also to be found in broken, bushy tracts. I have personally seen them in the wooded country on the East Coast, in a tract lying between the sea and a practically (to them) impassable range of mountains. In view of the number and variety of the carnivora there existing at the time, the survival of these birds was very surprising indeed. But it was only in the southwestern deserts that I had opportunities of observing the ostrich's habits. The observations made are necessarily scanty and incomplete. The shy and elusive nature of the bird is an almost insuperable bar to any connected scrutiny. The mere approach to a nest may cause the loss of a whole brood, for if the birds be badly scared they may not return. Even an unobliterated spoor in the vicinity of a nest may cause them to abandon it.
Another danger lies in the possibility of the eggs being scorched, or chilled, when the birds decamp-according to
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whether heat or cold prevail. But the greatest danger arises from the jackal, which is almost invariably to be found in the vicinity of a nest, waiting for an opportunity to maraud. The usual way in which a jackal does mischief is by rolling an egg out to the rim of sand surrounding the nest, and then pushing it back hard with his nose. This cracks the egg possibly also the one it strikes against. Occasionally two, or even three jackals will attack a nest at the same time, and fight vigorously over the contents of each egg as it is broken. The havoc then wrought may easily be imagined; it usually results in the abandonment of the nest.
Sometimes the white-necked raven (Corvultur albicollis) coöperates with the jackal. He will carry a small, heavy stone up into the air and drop it into the nest. Jackal and raven then share amicably the contents of the smashed egg. When only one, or perhaps two, eggs have been destroyed, the birds when they return may eat up the broken shells and go on sitting.
In the desert one could not avoid constantly associating the jackal with the ostrich. The central area of the Great Bushmanland waste is usually completely arid. It is absolutely level, except where the barren sand-dunes intrude over its northern margin. Of the larger fauna one finds in it only the oryx and the ostrich But in the breeding-season of the latter, central Bushmanland literally abounded with jackals especially in the vicinity of the ostrich nests. It was clear that the marauders were there for the purpose of preying on the eggs or the newly hatched chicks. So far as could be ascertained, there was literally nothing else for them to eat. The recognizable contents of the stomachs of jackals shot at this season were invariably the spoil of ostrich nests. It was quite exceptional to locate a nest without at
least one fresh jackal-burrow in its vicinity. More than once I have seen the cock in fierce pursuit of an interrupted marauder who, twisting and doubling, — yelping dolorously the while, made frantic efforts to reach his burrow. The jackal usually escapes, but not invariably. In the vicinity of recently abandoned nests, one occasionally found evidence indicating that some skulking brute had met a violent and richly deserved end.
The association of the jackal and the ostrich appears in ancient myth and literature. Flinders Petrie relates that in prehistoric Egypt, when the king was slain, the door to the underworld was supposed to be opened by the jackal, and through it the soul was wafted on an ostrich feather. In Job, in Isaiah, in Micah, and in Lamentations, ostriches and jackals are mentioned in the same text.
The ostrich hates the jackal implacably, but does not fear him. As a matter of fact the only creature the domesticated ostrich dreads is the dog. So fearless is he that he will unhesitatingly attack anything else which he deems to be an enemy, no matter how formidable; and as enemies he is apt to class all intruders upon what he considers to be his domain. Mr. Cronwright-Schreiner mentions the case of an ostrich charging a moving locomotive. Several instances have occurred of men having been kicked out of the saddle. But let a dog of any description appear, and the fiercest bird will almost invariably flee with every indication of terror. This is probably due to race-memory. The wild dog (Lycaon pictus) was formerly common all over South Africa; it frequented both forest and desert, ranging freely and hunting in packs which occasionally numbered over fifty individuals. The wild dog is now rarely met with except in a few of the densely bushed areas. But even
yet their melodious hunting-cry, 'Ho-ho-ho-ho,' - or their short, sharp bark, may be heard at night echoing through the scrub-filled gorges of the Great Fish River valley, in the Cape Province. It may easily be imagined what an ever-present terror the ostrich was subjected to when packs of these creatures, insatiably ravenous, roamed over the country, as they undoubtedly did less than a century ago.
The making of the nest by the breeding cock and his mate is a simple and rudimentary process. From the nature of the case, the observation of wild ostriches in the act of nidification is a practical impossibility. But one has ample opportunity of observing the nest-building of domesticated birds. A cock and a hen select some sandy spot, usually slightly higher than the surrounding ground and as a rule in the vicinity of some low bush. The cock, lying on his breast, kicks the sand out backwards and sideways. A slight depression is thus formed, surrounded by a low, irregular ridge. In the formation of the latter the hen assists in a futile way; she walks round, picking up spoonfuls of sand in her beak and dropping them on the ridge. During this operation she droops and flutters her wings, making a clicking noise with their joints. She soon afterwards begins laying, depositing an egg which weighs about three pounds every second day. Some hens will sit almost from the beginning of the laying period; others will wait until almost the full number of eggs has been laid. This number apparently varies among wild birds, from ten to twenty. The eggs are ivory-white in color and are minutely pitted all over. One wonders why the coloration is not protective, as in the case of nearly all birds that nest in open spaces. Possibly the heat of the sun may account for this.
The low ridge surrounding the nest