The ostrich would appear to be a bird of many enemies, from the following statement in Sir J. E. Alexander's narrative of his Expedition of Discovery in South Africa:

"According to native testimony, the male ostrich sits on the nest (which is merely a hollow place scooped out in the sand) during the night, the better to defend the eggs from jackals and other nocturnal plunderers. Towards morning, he brummels, or utters a grumbling sound, for the female to come and take his place; and she sits on the eggs during the cool of the morning and evening. In the middle of the day, the pair, leaving the eggs in charge of the sun, and 'forgetting that the foot may crush them, or the wild beast break them,' employ themselves in feeding off the tops of bushes in the plain near the nest. Looking aloft at this time of day, a white Egyptian vulture may be seen, soaring in mid-air, with a large stone between his talons. Having carefully surveyed the ground below him, he suddenly lets fall the stone, and then follows it in rapid descent. Let the hunter run to the spot, and he will find a nest of, probably, a score of eggs, (each equal in size to twenty-four hen's eggs,) some of them broken by the vulture. The jackal, too, is said to roll the eggs together to break them; and the hyÆna pushes them off with his nose, to bury them at a distance."