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A History of the Birds of New Zealand.

Glaucopis Wilsoni. — (Blue-Wattled Crow.)

Glaucopis Wilsoni.
(Blue-Wattled Crow.)

  • Glaucopis wilsoni, Bonap. Consp. Gen. Av. i. p. 368 (1850).

  • Callœas wilsoni, Gray, Ibis, 1862, p. 227.

  • Callœas olivascens, Pelz. Verh, zool.-bot. Gesellsch. Wien, 1867, p. 317, note.

  • Glaucopis olivascens, Finsch, J. f. O. 1870, p. 324.

Native name.—Kokako.

Ad. suprà schistaceo-cinereus, subtùs paullò cyanescens: loris cum vittâ frontali angustâ, regione oculari mentoque nigerrimis: facie laterali et gutture paullò canescentibus: fronte posticâ et supercilio indistincto albidis: carunculâ rictali ovali utrinque cyaneâ: remigibus et rectricibus nigricantibus dorsi colore lavatis: rostro et pedibus nigris: iride saturatè brunneâ.

Juv. dorso toto olivaceo-fusco: abdomine toto cum hypoehondriis et subcaudalibus pallidè cinereo-brunneis: carunculis minoribus, pallidè cyaneis.

Adult male. General plumage dark cinereous or bluish grey, tinged more or less on the upper surface of the wings and tail and on the rump and abdomen with dull brown; a band of velvety black, half an inch broad, surrounds the base of the bill, fills the lores, and encircles the anterior portion of the eyes; immediately above this band and continued over the eyes light ashy grey, shading into the darker plumage; quills and tail-feathers slaty black. Irides blackish brown; bill and legs black. The wattles, which form a distinguishing feature in this bird, are, during life, of a bright ultramarine-blue; but they fade soon after death, and in the dried state become almost black. Total length 17·25 inches; extent of wings 20·5; wing, from flexure, 7·25; tail 7·75; bill, along the ridge 1·25, along the edge of lower mandible 1; tarsus 2·5; middle toe and claw 2·15; hind toe and claw 1·5.

Female. Similar to the male, but somewhat smaller and more deeply tinged with brown on the lower part of the back, rump, and abdomen. Total length 17 inches; extent of wings 19·75; wing, from flexure, 6·6; tail 7·25.

Young. The young of both sexes have the whole of the back and the upper surface of the wings and tail, as well as the sides of the body, dull olivaceous brown; the abdomen and under tail-coverts yellowish brown; the wattles smaller than in the adult and of a pale blue colour.

Nestling (only partially fledged). Frontal band very inconspicuous except in front of the eyes; wattles extremely small and of a pinky colour. The plumage as in the adult but duller, and the wing-feathers washed on their outer vanes with brown.

Note. Professor Hutton is of opinion that the female is “rather larger than the male;” but my observations lead me to an opposite conclusion. I must admit, however, that I have found the size somewhat variable in both sexes. The wattle is always appreciably smaller in the female. In a pair from Wainuiomata, that of the male measured ·75 of an inch in diameter, and that of the female only ·5, besides being less rounded in form.

Varieties. There is a fine albino specimen in the Colonial Museum, obtained in the Rimutaka ranges and presented by a settler, who had it alive for several months. The whole of the plumage is white, with a creamy tinge on the fore neck and underparts; the shafts of the quills and tail-feathers conspicuously page 2 whiter; the caruncles very small and colourless; bill horn-coloured; feet yellowish brown; the tail-feathers somewhat abraded at the tips.

Another abnormal specimen in the same collection (received from the Wairarapa district) has the entire plumage of a washed-out ash-grey colour, paler and tinged with brown on the quills and tail-feathers. There is an approach to the normal bluish-grey colour on the throat and towards the edges of the frontal patch, which is dull brown instead of velvety black; bill and feet brown; caruncles faded to the same colour.

Obs. As will be seen from the above synopsis, I am unable to admit the so-called Glaucopis olivascens to the rank of a distinct species. It was founded on a specimen obtained at Auckland by M. Zelebor, and the diagnostic characters by which it is distinguished from G. cinerea are the brownish-olive colour of the back, wings, and tail, the greyish olive of the underparts, its greater size, and the “dusky colour of the mouth-caruncles.” As I have already shown, this description applies to the young of G. wilsoni. The dusky colour of the wattles is of no value as a specific character, because, as already mentioned, these appendages entirely change colour in dried specimens, leaving no trace of the original blue. Even in the living bird the colour of the wattles varies considerably in its tone, according to age and other physical conditions; and Dr. Hector has observed that when in confinement its wattles undergo remarkable variations, the exterior margin sometimes assuming a decided yellowish tinge, and again changing back into blue. Dr. Hector writes to me that of three specimens caught together, of which the sex was ascertainéd, two with olive-brown backs and very small wattles proved to be males, while the third, which had large wattles, of a deep blue colour, and only a slight tinge of brown on the upper parts, was unmistakably a female; and he expresses his belief that Glaucopis olivascens is the male of G. wilsoni. Accepting the result of Dr. Hector’s dissection as conclusive evidence of the sex in each case, I should be inclined to pronounce his two brown-backed males birds of the first year, and the female an adult in full breeding-plumage. I may add that the bird from which my description of the adult male is taken was shot in company with two others (an adult female and a young male), all of which were carefully sexed by myself.

This singular representative of the Crow family is sparingly dispersed over the North Island, being very local in its distribution. It is met with more frequently in the wooded hills than in the low timbered bottoms, but its range is too eccentric to be defined with any precision. During many years’ residence at Kaipara, north of Auckland, I never obtained more than five specimens, all of which were shot in the low wooded spurs of the Tangihua ranges. In particular localities, however, even further north, it is comparatively plentiful: for example, between the headwaters of the Wairoa and Whangarei rivers there are several strips of forest in which I never failed to meet with the Kokako; and in the Kaitara ranges in the Whangarei district it was, till within the last few years, rather abundant. I have heard of its occurrence in various parts of the Waikato district*, and in certain localities in the Hawke’s Bay and Wellington provincial districts it is far from being an uncommon species. During the autumn months it is comparatively plentiful in the Mangorewa forest between Tauranga and Rotorua. The traveller, at this season, frequently meets with it hopping about along the road or among the bushy branches of Solanum on either side.

The Kokako is adorned with fleshy wattles of a brilliant blue colour, which spring from the angles of the mouth, and when the bird is in motion they are compressed under the chin. The first specimen obtained from the Tangihua ranges was a fine bird in full plumage; but the Maori who brought it had torn off the beautiful wattles and pasted them, by way of ornament, on his dusky cheeks.

The notes of the male are loud and varied; but the most noticeable one is a long-drawn, organnote of surpassing depth and richness. I have not been able to discover whether the female is

* The Maoris state that it is common at Taupo and at Maungatautari, one of those whom I questioned on the subject observing, “Where the range of the Huia ceases, that of the Kokako begins.” Reischek met with several on the Great Barrier, but never saw it on the Little Barrier, nor on the Hen and Chickens. Lying off Cape Brett, the southernmost head of the Bay of Islands, there is a wooded islet called by the Maoris “Motukokako,” in allusion to its having been at one time inhabited by this bird.

page 3 similarly endowed, but I have often heard two or more Kokakos, each in a different key, sounding forth these rich organ-notes with rapturous effect; and it is well worth a night’s discomfort in the bush to be awakened at dawn by this rare forest music. I never hear it without being reminded of Waterton’s saying of the pretty snow-white Campanero, that “Actæon would stop in mid-chase, and Orpheus himself would drop his lute” to listen to its toll. Another of its notes may be described as a loud cackle, while others, again, are scarcely distinguishable from those of the Tui, resembling the soft tolling of a distant bell; but it is only in the early morning that they can be heard to perfection. It has another note, which is very much like the mewing of a cat; but this is only occasionally heard, and then immediately before rain, indicating, it would seem, a highly sensitive nature.

In the pairing-season the male bird loves to display himself before the other sex, arching his neck, spreading his wings, and dancing round the mate of his choice in a very ludicrous manner. They manifest much mutual attachment, and often continue to associate in pairs long after the cares of reproduction have been got rid of and the brood of young ones have grown up and dispersed.

This species subsists chiefly on small fruits and berries, but, like all the members of the family to which it belongs, it will readily partake of insect food of every kind. I have sometimes found its crop distended with the ripe pulpy seed of the tataramoa (Rubus australis), or with the berries of the N.Z. jasminekaiwiria (Parsonia albiflora) and kareao (Rhipogonum scandens); and it is said to feed also on the leaves of the thistle and wild cabbage. The branch depicted in the Plate is that of the native fuchsia, or kohutuhutu, the fruit of which forms a part of its favourite diet. When feeding, it often uses its feet, after the manner of a parrot.

Its wings are small and rounded, and its flight is consequently feeble and generally limited to very short distances. Its progression through the forest is usually performed by a succession of hops, the wings and tail being partially spread—a movement precisely similar to that of the Huia (Heteralocha acutirostris).

The stomach of this species consists of a very muscular sac, with a tough epithelial lining or integument, which peels off readily on being pulled, as with the fruit-eating Pigeons and some other birds. The plumage is beautifully soft and silky, owing to the peculiar texture of the feathers. The wattles are smooth and somewhat glossy, but their rich cerulean colour gradually fades out after death.

In disposition the Kokako inherits the true characteristics of the Crow family, being inquisitive, shy, and crafty. I purchased a live one from the Otaki natives in the winter of 1862, and as it shared my apartments for nearly a week (much to the discomfiture of my excellent landlady), I had a good opportunity of studying its habits and character. I was often much amused with the tricky manœuvres of this sprightly bird, and I regretted the accident which deprived me of so intelligent a companion. It generally remained concealed under a side table in a dark corner of the room; but in cold weather was accustomed to steal quietly to the inside of the fender, in order to get warmth from the fire. My presence had become familiar to it, but on the entrance of a stranger it would immediately spring out and hop away to its dark retreat under the corner table.

The bird represented in the Plate is one of a pair shot on the Poroporo ranges during the Huiahunting expedition of which an account is given further on. They were found perched in the midst of a superb bunch of puawhananga (Clematis indivisa), and feeding with avidity on the white petals, stopping at intervals to coy with each other and converse in a low musical twitter. The mated pair, with their unique floral surrounding, formed a lovely picture of real nature.

On dissecting the male, I found the whole of the viscera and even the membrane and skin covering it stained to a vivid blue; and on opening the stomach, I found it crammed with comminuted vegetable matter of a perfectly black colour. On examining some of this matter after washing it in cold water, I found that it was in reality composed of Clematis-flowers, the change in colour being apparently due to the action of some acid in the bird’s stomach.

Mr. Reischek found a nest of this species in a bunch of Astelia, the birds having simply made a page 4 round depression in the centre of the clump and placed a few dry twigs there. There were three young birds. Two of these sprang out of the nest on his approach, but were afterwards shot; the youngest he managed to catch before it could escape, and from this I have taken my description of the nestling. On another occasion he met with the nest near the wooded summit of the Waitakere ranges. It was a large irregular-shaped structure, composed of twigs and moss coarsely put together, and placed high up on a miro tree. The young birds (three in number) had just left the nest, but had not yet quitted the tree. They were shy and wary, and, on an alarm being sounded by one of the parent birds, they immediately secreted themselves in the thick foliage, from which it was found impossible to dislodge them. This was on January 3rd, which fixes approximately the breedingseason; although my son discovered a nest at Whangarei, containing three well-fledged nestlings, at a somewhat earlier date.

I agree in the opinion expressed by Mr. Kirk* that the egg brought to the Colonial Museum by Mikaera on October 20, 1885, and disposed of as the egg of the Huia, is in reality that of the present species. Subsequent events have shown that Mikaera’s testimony cannot be depended on; and no credence can be given now to his statement that it was “taken from a cavity in a dead tree.” The egg contained a young bird, apparently just ready for extrusion, and both embryo and shell are now in the Museum collection. The egg is ovoido-conical in form, measuring 1·45 by 1·05 inches, and is of a pale stone-grey, irregularly stained, freckled, and speckled with purplish grey, the markings in some places running into dark wavy lines. The chick has the bill very stout, with the caruncles at the angles of the mouth well developed and of a flesh-white colour. The whole of the body is bare, with the exception of what appears (in spirit) to be strips of coarse, black, hair-like filaments, from one half to three quarters of an inch in length, but which are in reality tufts of extremely fine downy feathers. A strip of these filaments encircles the crown, a line passes down the course of the spine, and there is another along the outer edge of each wing and behind each thigh.

Accepting, as I do, the view so well formulated by Professor Parker, that “in all respects, physiological, morphological, and ornithological, the Crow may be placed at the head, not only of its own great series (birds of the Crow-form), but also as the unchallenged chief of the whole of the Carinatæ”, I have, in my systematic arrangement of the New-Zealand ornis, accorded the foremost rank to the family Corvidæ, instead of placing the Turdidæ at the head of the list as is now the fashion with writers on Systematic Ornithology. Some doubts, however, having hitherto existed as to the true position of the genus Glaucopis, I was glad of the opportunity to place a skeleton of this species in the hands of Dr. Gadow, of Cambridge, in order that he might investigate its natural affinities. That gentleman made a critical examination of the bones, and compared them with those of Strepera, Gymnorhina, Paradisea, Struthidea, Graucalus, Ptilonorhynchus, Heteralocha, and Sturnus, with the following general result. He finds that Glaucopis is a Corvine form, being closely allied to the Austrocoraces, a group of birds which form a connecting-link between the true Corvidæ and the Laniidæ. It agrees with Strepera, and shows considerable similarity in structure with Ptilonorhynchus, although Glaucopis presents in its skull, sternum, and sacrum several characters which are peculiar to the genus. Struthidea agrees with Glaucopis by far less than might have been supposed, whilst Graucalus is still further removed, being apparently on the line through which Glaucopis reaches the Muscicapine forms. Dr. Gadow sums up the results of his investigation by saying that “if a Satin-bird could be induced to marry a Piping-Crow, their offspring might, in New Zealand, become a Glaucopis.”

* Journal of Science, 1882–83, vol. i. p. 262.

Trans. New-Zealand Instit. 1875, vol. viii. p. 192.

“There are, of course, innumerable points in regard to the Classification of Birds which are, and for a long time will continue to be, hypothetical as matters of opinion, but this one seems to stand a fact on the firm ground of proof” (art.“Ornithology,” Encyel. Brit., by Prof. Newton, F.R.S.).