(1713) Pseudogyps bengalensis (Gmelin).
THE INDIAN WHITE-BACKED VULTURE.
Pseudogyps bengalensis. Fauna B. I., Birds, 2nd ed. vol. v, p. 19.
This, the most common of all our Indian Vultures, is found over the greater part of India and Burma, but does not occur in Ceylon. In Sind, parts of desert Rajputana and of the Punjab it is rare. It is also found in Siam and Indo-China and in parts of the Malay Peninsula.
As this bird lives almost entirely by scavenging it is naturally more common round towns and villages than elsewhere, but it also sometimes breeds hundreds of miles from any human habitation, though such nests may not number one in every thousand. They ascend the hills for two or perhaps even three thousand feet but not in great numbers and, when they breed in the hills, the nests are nearly always solitary, while in the plains they often breed close together and sometimes in large colonies.
Hume says : “I have seen as many as fifteen nests on one Peepul-tree, and as many as a hundred on a group of trees lying within a circle of 200 or 300 yards in diameter.” In Sind Scrope Doig found a colony of about forty pairs breeding on some large Babool-trees growing in an island in the middle of a large swamp. Personally I have never found more than two or three nests on the same tree, though about a dozen pairs bred on some huge Mango- trees in our garden in Dacca and probably some fifty or more pairs bred within half a mile of the house. On one occasion in Dacca in early December two orderlies and I examined exactly fifty nests, and undoubtedly could have found more had we had time,
I think they breed invariably on trees and, where they are obtainable, on big trees. In Bengal and Assam Mango-trees are undoubtedly the favourites for building in. Hume, however, says : “Banyan and Peepul are their favourite trees, I think ; but I have found them breeding on the neem, tamarind, arjun and others ; in every case, however, on large trees.”
Anderson considered the various Fici to be the favonrite building trees, while in Bombay Davidson, Vidal and others found most nests in Mango and Cotton-trees. No one has recorded their building on palms, yet I have seen dozens of nests built on various palms, principally coconut, in gardens in the outskirts of Calcutta and in many other places in the 24th Parganas. In such cases the nests rest right up on the crown of the palms and in high winds look very precarious. Nests built close to the ground are exceptional, but there was a nest for many years in quite a small Jack fruit- tree in the compound of the Circuit-House in Dacca which was certainly not more than 15 feet from the ground.
The nests vary considerably in size but, as they are often repaired and added to for several consecutive years, they sometimes attain a great bulk. New nests are roughly about 2 feet in diameter by 6 or 8 inch as deep, but I have seen old neats as much as 5 feet across by fully 4 in depth. Although they look as if very roughly and clumsily put together they stand a great deal of pulling about before they break up. Moat of the material used consists of green branches tom off the trees with the leaves still attached ; the twigs of these when interlaced become quite firmly locked, the dead and dry sticks pushed in among them adding further to their stability. Most nests have very shallow cavities for the eggs, often only a few inches deop, but sometimes the hollow may be a foot deep, while Hume mentions one “which was a regular deep cup, in which a moderately sized sheep might have been stowed away." There is nearly always a rough lining of green twigs and leaves, but these are not renewed during incubation and, often, all sorts of rubbish is mixed with the green leaves. I have seen wool, bits of skin, cloth etc. often made use of and scraps of indescribable filth. Many nests are very evil smelling, while others, equally old in appearance, axe quite inoffensive.
The great majority of White-backed Vultures lay in November, December and early January, but I have taken eggs in the middle of October and others as late as the first week in March. These latter may be eggs replacing others which have been destroyed, for I have frequently found that this Vulture will lay again in the same nest if the first egg be taken when fresh. Butler also records that he took four fresh eggs from four nests on October 20th and that on the 8th November all four had laid again, while in two other nests from which he bad taken much incubated eggs the females were sitting and would probably have laid later.
Only one egg is laid and, though Anderson once took three eggs from the same nest and once two, these were not the product of the same bird.
The eggs vary greatly ; most are white or white faintly marked with pale red or pale yellowish-brown. Many are, however, quite well marked in various ways with reddish-brown, light red or grey brown, while a few have secondary blotches of lavender-grey or pale inky-grey. The markings are rarely at all bold in character but, occasionally, even such as these are to be met with. I have one egg which has the whole larger end very handsomely mottled with brick-red and lavender ; another densely speckled and spotted with brick-red over the whole surface and, yet a third, with large deep brown blotches scattered boldly at the larger end. Every type of egg may be seen between these extremes as well as eggs devoid of all marking.
One hundred eggs average 85.8 x 64.2 mm. : maxima 107.0 x 66.0 and 90.0 x 69.0 mm. ; minima 80.5 x 64.0 and 83.0 x 61.0 mm. A tiny egg, measuring only 64.5 x 51.0 mm., had a chick fully formed ip it, while I have seen other pigmy eggs which were fertile.
Both sexes build the nest, the male collecting material while the female puts it in position, and both male and female take part in incubation, which I believe takes forty-five days.
The female when incubating often sits very close, having some¬times to be literally pushed off the nest but I have never known her to show any fight, though she may sit on a branch a few feet away uttering croaks and hisses.
In copula and before the act both sexes indulge in tremendous roaring which, however, is not so loud as that of the Black Vulture. I have never seen copulation take place in the air, but the Eastern Bengal shikaries say that this does sometimes take place.
1713. Pseudogyps bengalensis
(1713) Pseudogyps bengalensis (Gmelin).