THE PIED HORNBILL
(Buceros bicornis)
THE hornbills, which are as large as big eagles, are some of the most extraordinary and bizarre of all birds, not only on account of the huge beaks from which they take their name, but from their strange and unique nesting-habits. In the enormous development of the beak these Old World birds are paralleled by the toucans of tropical America, although the two groups are in nowise nearly related. Such a huge and apparently unnecessary structure might at first sight seem too heavy and bulky for the bird by which it is carried; but internally the beak is generally a mere delicate tissue of bone, so that its weight is really very slight. Indeed, these enormous beaks are in most cases probably much less of an incumbrance to their owners than are the matinee hats favoured by ladies of the present day.
The pied, or double-horned species, the hornray of the natives, inhabits the dense forests of the Indo-Malay countries from the Himalaya and the Indian peninsula to the south of China and Sumatra. The glossy plumage is mostly black above, with the under-parts, the neck, the tips of the flight feathers, and the tail feathers more or less white or whitish, the upper half of the huge beak, with its horn-like appendage, being reddish yellow, and the lower half yellow. The total length of the bird, which is the largest member of the whole group, exceeds a yard. The so-called “horn,” or casque, forms a more or less flat and oblong platform on the upper part of the beak and the fore part of the head, terminating in front in two obtuse corners. On the other hand, the same appendage in the nearly allied rhinoceros-hornbill, or engan (Buceros rhinoceros), is much more horn-like, as it turns up into a recurved point in front.
The range of the hornbill group includes Africa, India, Malaya, Celebes, and New Guinea and the neighbouring islands as far as the Solomon group. The ground-hornbills are solely African, while the hollow-casqued section has a distribution equivalent to that of the group. One very remarkable Malay species, the solid-billed hornbill, the teban-mertua of the Malays (Rhinoplax vigil), differs from all the rest in having the beak and casque solid. This species is much hunted by the Chinese for the sake of its beak and casque, which have a structure resembling ivory, and are used as a substitute for that material in carving; while it is further remarkable for its bare neck and the elongation of the middle pair of tail feathers.
hornbill
The flight of hornbills is heavy and noisy, the swishing sound produced by the wings being audible at a great distance. The whole body of thesebirds is permeated by air-tubes connected with the wind-pipe, and it is said that the movement of the air in these increases the noisiness of the flight.
Mountain-forests bordering valleys, and big forests near rivers, are the favourite haunts of the typical hornbills. Here the great birds perch in flocks which may number a score in individuals; for hours together they sit motionless, with the neck drawn back on to the body, and the body itself pressed down on to the feet.
Their food consists chiefly of the fruits of the trees in which these birds take up their quarters, the favourite fruit being figs; but in captivity hornbills will eat fruits of all kinds, as well as animal food. These birds kill every small creature that comes in the way, and throw them up in the air before swallowing the body. When perching, hornbills utter from time to time a loud cry, recalling the bark of a dog, this changing into a loud scream when they are wounded.
The most remarkable feature connected with the habits of these birds is, however, connected with their nesting arrangements. As was first observed in India in 1855 by a military officer devoted to outdoor natural history, when the female has laid her clutch of eggs, varying in number from two to half a dozen, in some hole in a tree and commenced to incubate, the male walls up the entrance to the apartment with clay, leaving an aperture only just large enough for her to protrude her beak and receive the food brought regularly by her hard-working mate. The object of this immuring process is doubtless to protect the female and her eggs or young from the attacks of birds-of-prey, or predatory arboreal mammals. Under these circumstances sanitary matters cannot, of course, be attended to, and the nest-hole, consequently, soon becomes an evil-smelling mass of abominable filth. In order that no time may be wasted, the female moults during the period of her confinement, a process which adds still more to the mess in the hole. The young, which come forth from the eggs almost naked, remain in the breeding-hole till they are fully fledged. To reach the food brought by her partner, the female, at any rate during the early stages of incubation, has to climb up to the aperture in the wall of clay.