Art. XXVI.—Notes on the Little Bittern of New Zealand (Ardetta maculata).
[Received by the Wellington Philosophical Society, March, 1874.] *
The first mention of the existence of a Little Bittern in New Zealand was made by Mr. Ellman (Zoologist, 1861, p. 7469), who gave it a place in his list of species, apparently on native authority.
The first recorded specimens (two in number) were obtained by Mr. Shaw, at Kanieri, on the West Coast, in March, 1868, and forwarded to the Canterbury Museum, where they are still preserved. Mention of these was made in my notes on Dr. Finsch's paper, read before the Philosophical Society of Wellington, in August, 1868 (Trans. N.Z. Inst., 1868, Vol. I., p. 110).
Subsequently a third specimen was obtained “in one of the swampy creeks that feed the Okarito Lagoon,” and another at the head of the Wakatipu Lake, above Queenstown, in the Province of Otago. The last-named specimen was described in a paper read before the Otago Institute, by Mr. Purdie, who proposed to name it Ardeola novŒ-zealandiŒ (Trans. N.Z. Inst., 1870, Vol. III., p. 99.) Mr. Potts afterwards referred the species to Ardetta pusilla, of Gould, and contributed to the Philosophical Institute of Canterbury some very interesting notes on its range and habits (Trans. N.Z. Inst., 1870, Vol. III., pp. 97–100.) In the “Birds of New Zealand” I have since given the historical synonomy, and shown that the title of maculata (Latham, 1801) has the oldest claim to recognition.
During a visit to Hokitika in the autumn of 1871, I received from Mr. Clapcott the skin of a fine male specimen, apparently in full adult plumage; and I afterwards secured, through the kind assistance of Dr. Garland, a second specimen (a younger male), both of which had been obtained in the vicinity of the township.
So far as I am aware, those I have enumerated are the only examples of this bird that are at present known, and none of these correspond to Mr. Gould's description of the adult female in Australia. If I recollect aright, one of the specimens in the Canterbury Museum is marked 0/+, and if the sex in this case was determined by dissection, I think it highly probable that our Little Bittern will prove to be distinct from A. maculata of authors.
As the species is evidently very rare in New Zealand, and may, ere long, become extinct, I am anxious to direct attention to the subject without delay, in the hope that some colonist who has the opportunity will investigate this point, and so enable us to decide finally whether our bird is in reality identical with that inhabiting Australia.
[Footnote] * Dated at London 30th December, 1873.
With this view I beg to lay before the Society a sketch, by Keulemans, of the two specimens which I brought to England, together with my already published descriptions.
Adult male.—Forehead, crown of the head, and nape bluish black; throat and front of the neck tawny buff, each feather shaded in the centre with brown; from the chin and down the foreneck an irregular streak of reddish brown; on the sides of the neck the buff passes gradually into a rich chestnut; and this colour is continued on the sides of the head, forming a broad streak over the eyes, and another, less distinct, to the angles of the mouth, mixed with tawny yellow on the ear-coverts; under parts pale buff, each feather centred more or less with black; on each side of the chest the black predominates, forming broad acuminate stripes; the whole of the back and the feathers composing the mantle bronzy black, tinged more or less with chestnut, the scapulars margined with tawny buff; quills and tail feathers bluish black, slaty on their under surface, the inner primaries, as well as their coverts and most of their secondaries, tipped with chestnut brown; the primary coverts and a patch of feathers near the flexure pale chestnut edged with fulvous, the former centred more or less with black; the small wing-coverts and the whole of the secondary coverts blackish brown, broadly edged with yellowish buff, and presenting a handsome appearance. Irides golden yellow; eyelids and bare space in front of the eyes yellowish green; bill dark brown along the ridge and at the tip, yellowish green on the sides and towards the base of both mandibles; legs and feet bright green, stained at the tarsal joint and along the toes with dark brown. Length 15 inches; wing, from flexure, 6.25; tail, 2; bill, along the ridge 2.2, along the edge of lower mandible 2.75; bare tibia .5; tarsus 2.1; middle toe and claw 2.5; hind toe and claw 1.5.
Young male.—Differs from the adult in having the plumage of the back darker, and the wing-coverts of a rich tawny buff, shading into chestnut on the secondary coverts and towards the flexure.
Remarks.—Mr. Gould, in his account of this species in Australia, states that the “sexes differ considerably from each other, the female being mottled and of a smaller size than the male;” and he gives the following description of the former:—“Head and back chestnut; wing-coverts very deep tawny, passing into chestnut on the tips of the coverts and secondaries; primaries grey, tipped with brown; tail black; sides of the neck pale chestnut; front of the throat and the under surface white, with a stripe of tawny down the middle, and a small streak of brown in the centre of each feather, the brown hue predominating and forming a conspicuous mark down the throat.” No specimen has yet been obtained in New Zealand answering to the above account. The young bird, from which I have taken my description, exhibits one or two new feathers among the wing-coverts, marked as in the adult with
a broad central streak of blackish brown, thus indicating a transition to the more variegated plumage; and Dr. Garland, who dissected the specimen, informs me that it proved to be a male.
There is no specimen of Ardetta maculata in the British Museum; and Mr. Gould informs me that his only examples of the bird were sent with the rest of his Australian collection to America many years ago. I have not, therefore, had any opportunity of investigating the subject further in this country.