A History of the Birds of New Zealand.
Hymenolæmus Malacorhynchus. — (Blue Duck.)
Soft-billed Duck, Lath. Gen. Syn. iii. pt. 2, p. 522 (1785).
Anas malacorhynchus, Gm. Syst. Nat. i. p. 526 (1788, ex Lath.).
Malacorhynchus forsterorum, Wagler, Isis, 1832, p. 1235.
Hymenolaimus malacorhynchus, Gray, Ann. Nat. Hist. 1843, vol. xi. p. 370.
Anas malacorhynchus, Forster, Descr. Anim. p. 94 (1844).
Ad. ubique clarè plumbescens, pileo saturatiore, paullò brunnescente: interscapulii plumis medialiter nigricantibus, gutture vix brunnescente: pectoris superioris et lateralis plumis pallidè castaneo medialiter notatis: subalaribus et subcaudalibus pallidè castaneo lavatis: rostro albicanti-corneo, ad apicem nigro: pedibus saturatè brunneis: iride latè flavâ.
Adult male. General plumage pale slate-blue, darker on the upper parts; the crown of the head and nape, as well as the scapulars and upper wing-coverts, olivaceous, with a slight metallic gloss; the secondaries with a narrow exterior margin of velvety black; the breast thickly spotted with dark chestnut, of which colour there are also a few obscure spots on the under tail-coverts. Irides bright yellow; bill white horn-colour, the tip and the lateral membrane black; legs and feet dark brown. Length 22 inches; extent of wings 29; wing, from flexure, 9·5; tail 4·5; bill, along the ridge 2, along the edge of lower mandible 1·75; tarsus 2; middle toe and claw 2·75.
Obs. I have observed that, as a rule, the specimens from the South Island have the pectoral markings more numerous and conspicuous, and the velvety margins on the secondaries more distinct.
Female. Slightly smaller than the male, but similar in plumage, excepting that there is little or no metallic gloss on the head and upper surface, less chestnut on the breast, and more on the under tail-coverts.
Young. General plumage lighter, and the underparts whitish; the green gloss which pervades the plumage of the upper parts in the adult almost entirely absent; hind head and nape dull cinereous brown; breast obscurely spotted with dusky and brown, sometimes barred with chestnut at the insertion of the wings; under tail-coverts dull rufous brown.
Nestling. “Bill horn-colour, lightest on the lower mandible, unguis rosy at the point, membraneous appendage slaty black, well overlapping the lower mandible, furnished with lamellæ along its basal half, which work against the finely serrated sides of the compressed basal half of the lower mandible; body covered with thick down, longest on the back; upper surface dull green, brightest on the back; over and behind the eye irregular streaks of white; under surface white; wings and upper part of thighs brownish; tail green above, at each side a patch of chestnut; under surface of the tail chestnut; legs and feet yellowish flesh-colour.”—Potts.
Far up the mountain-gorge, where the foaming torrent, walled in on both sides, rushes impetuously over its shingle-bed, surging around the huge waterworn boulders that obstruct its course, and forming alternately shallow rapids and pools of deep water, there the Blue Duck is perfectly at home, page 277 and its peculiar whistling or sibilant note may be easily distinguished amidst the noise of the rushing waters; indeed, as Mr. Travers has already suggested, the bird appears to have been specially endowed with this singular note in consequence of its frequenting such localities. A stray one is sometimes carried down during a freshet into the still reaches, or even to the very mouth of the stream, but it speedily works its way back again to its favourite mountain-haunts. It is a very tame or stupid bird, often remaining perfectly quiet on a projecting boulder till you approach within a few feet of it; then sidling off into the water it swims into the nearest rapid and allows itself to be hurried down by the current. It seldom dives, and takes wing only when fired at or closely pressed; but it swims with considerable rapidity, the head being carried low and inclined somewhat forward. It has the faculty of turning itself round in the water, and without losing ground, however rapid the stream, as though its body were worked on a pivot, a performance no doubt aided by the peculiar lengthened shape of its tail. It climbs the slippery face of the rocks with facility, assisting itself in the ascent by its wings, which are armed at the flexure with a hard protuberance or knob. As already mentioned, it utters a peculiar whistling note, from which it derives its native name.
It is somewhat nocturnal in its habits, and seems to become more active in its movements towards nightfall, when it sometimes makes a comparatively long flight in its passage from one mountain-torrent to another.
Some five-and-twenty years ago, in consequence of the death by drowning of the well-known botanist, Dr. Sinclair, I paid a visit with his nephew to the scene of this unfortunate accident, near the head-waters of the Rangitata, and in this secluded country I found these birds at that time so tame that I could almost catch them with my hand.
I believe this Duck is to be found at the sources of all mountain-streams, for although I never succeeded in getting a specimen at the far north, its name was perfectly familiar to the natives of that part of the country. Mr. Cheeseman, however, writes to me:—“I have never heard of a specimen being obtained north of Auckland. Mr. Spencer has shot it at the head of the Kaueranga, Thames. Mr. R. E. M. Campbell informs me that it is plentiful at the sources of the streams forming the Wairoa river (discharging into Tauranga harbour), and Mr. W. T. Firth has seen it in the Wairere stream, near Matamata. I have noticed it in the upper part of the Waitetuna.”
Captain Mair informs me that the Wio is plentiful in all the mountain-streams in the Urewera country. When marching with the native contingent in pursuit of Te Kooti, as many as forty or fifty were sometimes caught in the course of a day, some being taken by hand, and others knocked over with sticks or stones, so very tame and stupid were they. A pair which he obtained as very young birds at Maunga-pohatu lived in the Kaiteriria camp for two years, associating freely with the domestic ducks, and fairly establishing themselves in the cooking-hut. They were particularly fond of potato and rice, and would readily take food from the hand. Ultimately they took to the lake and disappeared.
My son met with a pair at the Pokaiwhenua falls, in the Upper Waikato, in the early part of February. He observed that they ascended the rapids by diving under the surface. They were very tame, and by imitating the whistling note of the duck, or the whirring call of the drake, he was able to bring them within a few paces of where he stood. He met with this Duck again at Owhaoko, in the upper waters of the Rangitikei and Moawhango rivers.
In the month of March I met with a pair in the turbulent rapids of the Kurupapango, in the Hawke’s Bay district. They appeared to fly well on being disturbed, and produced almost constantly a soft whistling cry, hardly distinguishable from that of the Harrier (Circus gouldi). Their ivory-white bills were a very conspicuous feature, even at a distance of a hundred yards.
Mr. Reischek met with it in the West-Coast sounds, and shot several at night far out on the water, thus proving that this Duck is sometimes marine in its habits. He likewise obtained page 278 specimens in the Pirongia ranges, in the Upper Waikato, and Professor Hutton received it from the Mokau district.
Its range may therefore be described as pretty general, although it is not very plentiful in any part of the country. It does not, however, occur out of New Zealand, nor has it any known ally.
In the autumn of 1863, I visited the upper gorges of the Manawatu river, and obtained a fine series of specimens in the various states of plumage. The crops of those which I opened were filled with a species of “caddis-worm;” and on turning out the contents I discovered the nest of this insect, consisting of a tough integument shielded by small angular stones firmly glued over the entire surface. The caddis-worms were of different sizes (none, however, exceeding an inch in length), light brown in colour, with a dark head armed with three nuchal plates, and furnished with six legs. This insect appears to exist abundantly in all our shingle-rivers, and as we may assume that it forms the chief, if not the only food of the Blue Duck, the troublesome task of dislodging the animal from its stone-covered cell appears to explain at once the use of the fleshy membrane which fringes the bill of this bird. That it is, at any rate, an expert, may be inferred from the fact that out of several hundred specimens taken from the crops of my birds, only one of these insects was invested with the case or integument, this having probably been swallowed by accident among the rest.
Several pairs of this Duck were kept for some months in the Acclimatization Gardens at Christ-church and became perfectly tame. They were ultimately shipped home to the Zoological Society.
Mr. Potts states that on examining an embryo of three weeks he found the form of the bill well developed, showing on the sides, near the end of the upper mandible, the peculiar membranous appendage of a darker colour than the rest of the bill, but that he was unable to discern the presence of lamellæ; the caudal down was produced to a remarked degree. The same accurate observer has furnished the following interesting account of the breeding-habits of this species:—“Sometimes it is a burrower, and its nest may then be found in a hole in a bank. I have found it concealed from view by overhanging sprays of those various Alpine veronicas which sometimes make the mountain-creeks in the back country perfect gems of beauty. The nest, like that of other ducks, thickly lined with down, generally contains five eggs of a deep cream-colour, elliptical in form, measuring 2 inches 8½ lines in length, with a diameter of 1 inch 9 lines. I have seen nests of eggs in October and November, but I have known the young brood to be swimming about by the end of September. We may therefore consider it one of our early breeders. As I have mentioned that it breeds in holes of banks, it is worth recording, perhaps, that I have found the nest in situations that did not afford any great amount of shelter; one such instance was met with on a spit in the Upper Ashburton river, about three miles below the glacier from which that river derives its source: the nest was placed in a solitary snow-grass tussock of moderate size, within two or three yards of the stream; it was made of grasses, the interior composed of cut grass like chaff, down, and a few feathers.”
Mr. Hill, school inspector, was up in the Ruahine ranges (Hawke’s Bay side) towards the end of November, and caught some young Wio there. They were very active in the water, diving persistently, and when hard pressed they took to the bank and endeavoured to secrete themselves.
The old birds remained on the water within sight and made no sign; but before the discovery of the young, they had tried to divert attention by feigning disability on the water, as if inviting pursuit.
There are several specimens of the egg of this bird in the Canterbury Museum. They are narrower or more elliptical in form than those of most other Ducks, measuring 2·6 inches in length by 1·7 in breadth; they are of a pale cream-colour, slightly tinged with green, and some of them much stained on the surface probably from contact with the bird’s feet during the process of incubation.