Art. XIII.—A Description of the curiously-deformed Bill of a Huia, (Heteralocha acutirostris, Gould), an endemic New Zealand Bird.
[Read before the Hawke's Bay Philosophical Institute, 9th August. 1886.]
A short time ago I received from a kind correspondent, a settler dwelling in the interior forest-land, the head of a Huia in a fair state of preservation, which he had then recently obtained from a Maori. This head is that of a female bird; the upper mandible of its bill being greatly and strangely deformed. From about 1 inch, or one-fourth of the normal length of the upper mandible from its base, it suddenly rises and remains at an angle of 45°, forming a regular ascending and suberect spiral of two large and equal curves, each being of ¾-inch open interior diameter; not unlike a gigantic corkscrew, and reminding one of the horn of the Strepsiceros. (See Plate IX.)
The total length of this deformed mandible, following the curves, is just 6 inches; its breadth at the widest part about the middle is 4 lines, which part is also flat above, and is devoid of nostrils; and its end or tip is sharply pointed, and vertical upwards; throughout its whole length it is much thicker, rounded, and very obtuse on the right side or edge, while the left edge is thin and sharp; the lower thin marginal base of the right edge of the mandible is also much produced and sharp, evidently larger than ordinary, arising from, I think, not having been worn away in use; while the corresponding opposite edge is much worn, being almost the only part of the upper mandible that could possibly be brought into serviceable contact with the lower mandible; its colour, too, is not that sure ivory-white of the healthy and normal bill, but more like that of common whitish horn.
The lower mandible is 2 ¾ inches long, being very much shorter and not so much curved as this portion of the bird's bill is in the normal state. The tip, too, is much more blunt, and is slightly worn or broken; on the left edge near the base is a tolerably large, worn depression or notch, where the upper mandible must have closed upon it in the efforts of the bird on receiving its food.
There is not the least indication of the upper mandible ever having been broken or bruised, and afterwards, in healing and using, grown out of its common natural form, and thenceforward assuming its present shape. The inference, therefore, is
that this bird must have been hatched with this peculiarly aberrant upper mandible; and, while we may reasonably suppose the parent birds assiduously fed it for some considerable time beyond the usual period of their young remaining unfledged, still, how it afterwards could have managed to exist and grow up seems truly wonderful! Especially when we consider the usual native food of the Huia, which consists of the larvæ of some of our largest beetles, (e.g., Prionoplus reticularis,) obtained by the bird industriously pecking and probing rotten logs and wood, much after the manner of the common Woodpecker. Besides, from its very strange configuration, it appears to have been far worse than merely useless, for it must have been always an obstacle in the way, and the means of keeping the bird's mouth always open.
From the general appearance, as well as from the extreme length, of this upper mandible, I should infer the bird to have been an aged one; for, according to Dr. Buller, the length of the bill of the female bird is from 4 to 4 ½ inches; but this upper distorted and unused mandible is no less than 6 inches long, while the lower one, which should correspond as to length, is only 2 ¾ inches! So, here we have two patent facts: 1, that the upper amorphous mandible grew continually, without being worn away through use; and, 2, that the lower one, having extra and constant work to perform, was consequently worn down and made defective far beyond its normal state and its natural power of growth-producing horn.
I have said that this head had belonged to a female bird: this is known by the greater length of the bill of the female bird, which is also narrower and much more curved than that of the male. For, while the bill of the female ordinarily measures about 4 ¼ inches, that of the male is only 2 ¼ inches, and is much more stout and strong, more wedge-shaped, and, consequently, less curved. Indeed, so great is the difference existing between the male and female birds in the form and length of their bills, that formerly, and for some considerable time, owing to their rarity and the scarcity of good specimens, the two birds were by our first ornithologists at Home believed to constitute two distinct species, and were consequently published as such.
I have already remarked that it seems almost a mystery how a bird with such a strangely deformed and all but useless bill could have managed to obtain its native food, so as to subsist and grow. We may, however, obtain a little light on this somewhat dark subject from an interesting paper on the Huia, written by Dr. Buller some 15 years ago for the Wellington branch of this Institute, and published in the third volume of their “Transactions;” Dr. Buller having had the peculiar and almost unique advantage of observing for more
than a year the habits of these birds while living in confinement; and from his pleasing paper I shall quote a few passages bearing more particularly on this part of my subject.
In the beginning of his paper, Dr. Buller observes:—“Their peculiar habits of feeding, which I have described from actual observation, furnish to my own mind a sufficient ‘reason’ for the different development of the mandibles in the two sexes, and may, I think, be accepted as a satisfactory solution of the problem. In the summer of 1864 I succeeded in getting a pair of live birds. I kept these birds for more than a year; and when the male bird was accidentally killed, the other, manifesting the utmost distress, pined for her mate and died ten days afterwards.”
“The readiness with which these birds adapted themselves to a condition of captivity was remarkable. Within a few days after their capture they had become perfectly tame, and did not appear to feel in any degree the restraint of confinement; for, although the window of the apartment in which they were kept was thrown open and replaced by thin wire netting, I never saw them make any attempt to regain their liberty.”
“They were fully adult birds, and were caught in the following simple manner. The Maori who had caught them attracted the birds, by an imitation of their cry, to the place where he lay concealed; then, with the aid of a long rod, he slipped a running knot over the head of the female and secured her. The male, emboldened by the loss of his mate, suffered himself to be easily caught in the same manner. On receiving these birds, I set them free in a well-lined and properly—ventilated room, measuring about 6 feet by 8 feet. After feeding freely on the huhu grub, a pot of which the Maori had brought with them, they retired to one of the perches I had set up for them, and cuddled together for the night.”
“It was amusing to note their treatment of the huhu. This grub, the larva of a large nocturnal beetle (Prionoplus reticularis), which constitutes their principal food, infests all decayed timber, attaining at maturity the size of a man's little finger. Like all grubs of its kind, it is furnished with a hard head and horny mandibles. On offering one of these to the Huia, he would seize it in the middle, and, at once transferring it to his perch and placing one foot firmly on it, he would tear off the hard parts, then, throwing the grub upwards to secure it lengthwise in his bill, would swallow it whole. … I sent to the woods for a small branched tree, and placed it in the centre of the room: it was most interesting to watch these graceful birds hopping from branch to branch, displaying themselves in a variety of natural attitudes, and then meeting to caress each other with their ivory bills, uttering at the same time a low affectionate twitter.”
“But what interested me most of all was the manner in which the birds assisted each other in their search for food, because it appeared to explain the use, in the economy of nature, of the differently formed bills in the two sexes. To divert the birds, I introduced a log of decayed wood infested with the huhu grub. They at once attacked it, carefully probing the softer parts with their bills, and then vigorously assailing them, scooping out the decayed wood till the larva or pupa was visible, when it was carefully drawn from its cell, treated in the way described above, and then swallowed. The very different development of the mandibles in the two sexes enabled them to perform separate offices. The male always attacked the more decayed portions of the wood, chiselling out his prey after the manner of some Woodpeckers, while the female probed with her long pliant bill the other cells, where the hardness of the surrounding parts resisted the chisel of her mate. Sometimes I observed the male remove the decayed portion without being able to reach the grub, when the female would at once come to his aid, and accomplish with her long slender bill what he had failed to do. I noticed, however, that the female always appropriated to her own use the morsels thus obtained. For some days they refused to eat anything but huhu, but by degrees they yielded to a change of food, and at length would eat cooked potatoe and raw meat minced up into small pieces.”
Dr. Buller also goes on to say that “Dr. Dieffenbach, in forwarding his specimens of the Huia to Mr. Gould in 1836,” [error, lege, 1839–41] “wrote:— ‘These fine birds can only be obtained with the help of a Native, who calls them with a shrill and long-continued whistle, resembling the sound of the Native name of the species. After an extensive journey in the hilly forest in search of them, I had at last the pleasure of seeing four alight on the lower branches of the trees near which the Native accompanying me stood. They came quick as lightning, descending from branch to branch, spreading out the tail and throwing up the wings.” (l.c.). From Dr. Dieffenbach seeing four on that occasion, I have little doubt of their being two pairs.
Moreover, and in further confirmation of much of the foregoing, I may briefly add what have at various times in past years, while travelling, come casually under my own notice respecting this bird. In some year in the decade of 1850 (I forget the exact one), I was, as usual, returning on foot from my annual journey to Wellington by the coast line, when one morning early, on the beach by the side of a small stream near Cape Turakirae (the west head of Palliser Bay), I suddenly came upon a single Maori, who had just then taken six of these birds, three males and three females; some were dead, killed in the capturing, and some were still alive. He told me that he
had seen them there on the low-stunted karaka trees (Corynocarpus lœvigata) the day before; and so, having prepared his materials, had returned thither early that morning, and had succeeded in taking them.* I am, however, not certain (now) that he had captured all. I might have bought them from him for a small sum, but I was too far away from my home in Hawke's Bay, with a long and heavy journey before me, and had no means at hand for preserving their skins. At that time (before, and for many years after), there lived at Mataikona, near Castle Point, a very curious eccentric old Maori chief named Pipimoho—a true type of the skilled old Maori tohunga, or knowing-man! Pipimoho was the only one in these parts who knew how and where to capture these birds; and this for a long time was his annual occupation, once or twice in the year to go to the inland forests from the East Coast, (to Puketoi and its neighbourhood), to snare the Huia; and this was done to supply the principal chiefs of Hawke's Bay—Puhara, Te Hapuku, and Hineipaketia, his superiors in rank. This quaint old man only died about three years ago. From him I have received many a curious and interesting relation, always wishing I had more spare time at command to obtain more.†
I have also seen this bird in captivity with the Maoris, kept in a large light cage of network for the sake of its tail-feathers (rectrices), which were plucked as they arrived at maturity; the Maoris fed them with cooked potatoes, and other similar soft vegetable food.
Dr. Buller, in the same paper, also mentions, and gives the figure of, a larger and more highly curved form of the bill of the female bird than is usually met with. (Loc. cit., tab. iii., fig. 3.)
Further, I may also briefly state that, among the Parrots, the Maori Kaka, (Nestor meridionalis, Gml.), which I have formerly seen kept in confinement by the Maoris, I have noticed a few with very deformed upper mandibles; those birds had been kept by them for several years, and were aged, and being fed only (and sparingly!) on soft vegetable food, generally cooked potatoes, their bills, from want of their regular natural attrition on the harder substances of the forest, became overgrown and deformed. Indeed, the poor prisoners had not the common chance allowed them of biting and tearing their perch, or any wood (and this from mere thoughtlessness and carelessness, or long-continued custom, on the part of their Maori owners), for they were invariably kept fastened by a bone ring or carved
[Footnote] * The finding of those birds here, far away from the forests and close to the sea-beach, is opposed to Dr. Buller's statement as to their narrow restricted mountain-forest habitat. (loc. cit., p. 24.)
[Footnote] † See “Trans. N.Z. Inst.,” vol. xiv., p. 54, for a pleasing anecdote concerning him.
circlet around one leg, and thus tied securely, but loosely, with a strong short cord to a slender polished cylindrical hard-wood spear, up and down which, for the space of 2 or 3 feet, the poor bird ran and danced and flapped his wings, always without water, and frequently in the hot burning sun, without any shade. These birds, however, were of great use to their owners for decoying other parrots for food, which through their means were often at set seasons slaughtered in large numbers.
Now, from all those interesting facts and observations relative to the habits and economy of the Huia, we may, I think, gather:—1. That these birds are quiet and social. 2. That they keep together in sexual pairs, and are therefore likely to be monogamous. 3. That the cock and hen are greatly attached to each other. 4. That they naturally and mutually help in their search after their own proper food. 5. That they can and do, without difficulty, make a thorough change in their diet or food, from animal to vegetable substances. And so, I think, we may reasonably conclude that the unfortunate female bird, to whom belonged this unnaturally distorted and almost useless upper mandible of her bill, was helped throughout a long life by her kind and attentive mate.