Other formats

    TEI XML file   ePub eBook file  

Connect

    mail icontwitter iconBlogspot iconrss icon

A History of the Birds of New Zealand.

Himantopus Albicollis. — (White-Necked Stilt-Plover.)

page break

Himantopus Albicollis.
(White-Necked Stilt-Plover.)

Himantopus albicollis, Buller, Trans. N.-Z. Inst. vol. vii. p. 224 (1874).

Ad. capite toto cum collo undique et corpore subtùs toto albis: interscapulio, scapularibus cum dorso summo et tectricibus alarum nigris: remigibus angustè albido terminatis: subalaribus nigris: dorso postico et uropygio albis: caudâ nigrâ: rostro nigro: pedibus pallidè cruentatis.

Adult. Head, neck all round, and all the under surface of the body, lower part of back, rump, and upper tail-coverts pure white; across the shoulders, scapulars, and upper surface of wings glossy black, with greenish reflections, the inferior primaries and the secondaries tipped with white; under surface of wings and the axillary plumes black; tail-feathers glossy black, Bill black; irides red; legs and feet pinky red. Total length 14·25 inches; wing, from flexure, 9·25; tail 3; bill, along the ridge 2·6, along the edge of lower mandible 2·9; bare tibia 2·2; tarsus 3·75; middle toe and claw 1·5.

Obs. The specimen from which the above description was taken is undoubtedly an adult bird, and is in a moulting condition, the glossy greenish-black feathers of the mantle replacing the brownish-black plumage of an earlier state.

Young. Has the head and neck as in the adult, but with the crown and nape more or less stained or washed with dark grey; all the feathers of the upper parts narrowly margined with brown.

More advanced state. The brown margins on the upper surface disappear, the plumage changing to dull satiny black with a greenish gloss, the clouded markings on the crown and nape, however, remaining unaffected. The adolescence of the bird in this condition of plumage is indubitably shown by its swollen tarsi.

Note. Through the kind attention of Mr. C. H. Robson, I have received from Cape Campbell a Plover clearly referable to the above species. From the enlarged condition of the tarsi below the joint, it is evidently an immature bird, and this will account for the crown and hind neck being tinged or faintly mottled with grey, these parts being wholly white in the adult. The flanks, rump, and under tail-coverts are clouded with black; tail-feathers on their inner web and towards the base white; the rest of the plumage as in my type.

In a paper which I communicated to the Philosophical Institute of Canterbury “On the Genus Himantopus in New Zealand” *, I discriminated, under the above name, a form which appeared to me to be specifically distinct from the two preceding ones.

Five or six specimens have since passed through my hands at various times, but most of these were in a somewhat immature condition of plumage, thus raising in my mind a doubt as to whether this bird may not, after all, be merely a seasonal state of H. novæ zealandiæ.

Mr. Seebohm is of opinion that my Himantopus albicollis is in reality the almost cosmopolitan H. melanopterus, and in his latest work, on the Charadriidæ, he accordingly states, as a fact, that the latter species has been met with in New Zealand. It has been known to occur in the Philippine Islands, and there would be nothing extraordinary in a few stragglers finding their way, at irregular intervals, to New Zealand. But after carefully examining the extensive series of specimens in the British Museum, I find it impossible to accept his determination of the species. Among other minor

* Trans. N.-Z. Inst. vol. vii. pp. 220–224.

page 28 differences, I find that H. melanopterus, at all stages of its growth, has a white or greyish tail, whereas H. albicollis in the adult state has a black one, and this alone would form a good distinguishing character. Again, H. albicollis has the primaries and secondaries tipped with white, whereas in H. melanopterus they are entirely black.

Mr. Hamilton, in his account of the birds of the Petane district (Hawke’s Bay), says * that “the White-necked Stilt occurs not unfrequently.”

As the subject, however, seems to need further investigation, it may be well to reprint here a portion of my paper referred to above:—

“Probably the most puzzling group of birds we have in New Zealand is that of the Stilt-Plovers, and my object in submitting the following notes is to make another step towards a better acquaintance with and elucidation of the species.

“In the first place, it is somewhat remarkable that New Zealand should possess certainly two, if not three, species of a genus of birds so peculiar that (if we except a small one said to exist on the west coast of Madagascar) each of the great divisions of the globe can only boast of one. Even Australia, teeming as it is with wading birds, is the home of only one species of Stilt (H. leucocephalus), which is also common to New Zealand, Ternate, Celebes, and Timor. The existence of a second species in this country (H. novæ zealandiæ) was first recorded by Mr. Gould in 1841. Since that date several other names have been added, and (owing to our imperfect knowledge of the seasonal and transitional states of plumage) the nomenclature has got into a state of confusion. As in all such cases, the only escape from this is a careful study of the species at all ages and at all seasons of the year, noting the changes of plumage that occur, and tracing their progress from youth to maturity.

“The present paper is intended to be a contribution of this sort, but as I have not collected or dissected any of the specimens referred to, it would be manifestly unfair to hold me responsible for the data. Particulars of season, sex, &c., I have been compelled to take on trust.

“For the purposes of this examination I have had before me forty-three specimens, in different conditions of plumage, belonging to the Canterbury Museum.

“There is no difficulty whatever in separating Himantopus leucocephalus, which is distinguished from H. novæ zealandiæ in the somewhat similar seasonal plumage by its purer and well-defined colours, its smaller bill, and appreciably shorter toes and claws. Of course specimens vary, and in a series like the present we meet with large examples of H. leucocephalus and small examples of H. novæ zealandice, but the general rule holds good throughout. The young are readily distinguished by the enlargement towards the distal end of the tarsus (a provision for the future lengthening of this bone), which diminishes with the growth of the bird. There are two fledglings in the collection, and as the description of the ‘young’ given in my ‘Birds of New Zealand’ (1st ed. p. 203) is taken from a somewhat older bird, I append the following notes:—

H. leucocephalus, juv.—Crown of the head, back, and upper surface of the wings brownish black, tinged more or less with brown, and many of the feathers being narrowly tipped with greyish white; hind neck greyish white, mottled with black in its lower portion; forehead, fore neck, and all the under surface, as well as the rump, white; the whole of the quills black, the inferior primaries and the secondaries narrowly tipped with white; tail-feathers black, edged with fulvous, and white at the base. (Obtained at Rakaia, Nov. 1872. Weight, 6 oz.)

Of Himantopus novæ zealandiæ I have given in the ‘Birds of New Zealand’ (1st ed. pp. 205–206) descriptions of the summer, winter, and adolescent states of plumage, and under the head of ‘Remarks’ I have referred to the numerous transitional states which have led to so much confusion in regard to this species. The description there given, however, of the adult in winter, I wish now to qualify by stating that the uniform dark plumage on the abdomen is by no means a constant character.

“First of all, as a result of my present examination, I feel bound to dismiss Himantopus spicatus, Potts, as having no claim whatever to the rank of a species. The type specimen is now before me, and the distribution of colours (as may be seen on reference to the published description) indicates a transitional condition. The extra length of leg (as compared with H. novæ zealandiæ) appears to be rather in the tibia than in the tarsus. Mr. Potts makes the black neck and breast his distinguishing feature; but there is another bird in the collection (a male) in which the tarsus is 4 inches and the tibia 2 inches—altogether a bird of smaller proportions—in which the distribution of colours is the same, although there is a less extent of black on the breast.

“I have already described (I.e. p. 204) the young of this species from two young specimens in the Canterbury Museum, the parentage of which was placed beyond all doubt by Mr. Fuller, who secured at the same time the two old birds in black summer plumage. I may add that these latter are still in the collection; the male is perfectly black, and the female slightly pied.

“A more matured example of the young bearing the following label, ‘Shot in Bottle Lake, Jan. 28, 1872; juv.—female; parent bird black,’ presents a general resemblance to the young of Himantopus leucocephalus, but on a close comparison the following differences are observable:—The crown is lighter, being of an almost uniform ash-grey; there is more greyish white

* Trans. N.-Z, Inst. vol. xviii, p, 127.

Op. cit. vol. v. p. 198.

page 29 between the shoulders, and the tail-feathers instead of being black are ashy white, the outer ones having a broad subapical mark of dark grey; and the axillary plumes, under the wings, instead of being black are pure white; there are fewer light margins on the wing-coverts; and the inferior primaries and the secondaries are more largely tipped with white. Some of these differences, however, may be due to the fact that this is a somewhat older bird. In the other specimens, mentioned above, the axillars are black, as in the young of H. leucocephalus.

“The collection contains nine perfectly black specimens. Of these eight are males; and, according to the labels, all of them were killed in summer Out of twelve other specimens more or less pied with white, only three are females, all of them (of both sexes) being also summer birds. The extent of white, however, varies considerably in birds shot at one and the same time, some exhibiting only a few white feathers on the neck and breast, whilst in others the white predominates. This irregularity of plumage may perhaps be accounted for on the supposition that the birds do not undergo the complete change at their first seasonal moult, but-at some later period—say in their second or third year.

“There are two specimens in the collection which are of more than ordinary interest, because they are quite distinct in appearance from either H. leucocephalus or H. novæ zealandiæ in their full plumage, and cannot, so far as I at present see, be a transitional state of either of those species. One of these, presented to the Museum by the late Dr. Barker, bears the following label, ‘Orari, Feb. 16, 1872, male,’ and appears to be in full adult plumage. The other, which is labelled ‘Saltwater Creek, April 1873, male,’ is apparently a less matured bird. On observing certain indications of a change from black to white in the latter, I at first supposed that the white head and neck might represent the true winter plumage of Himantopus novæ zealandiæ; but, as directly opposed to this view, Dr. Barker’s specimen, which I am disposed to regard as a distinct species, was killed towards the end of summer. In this bird the entire head and neck, with the breast and underparts, are pure white; rump and upper tail-coverts also white; back, scapulars, and upper surface of wings and tail glossy black, the inferior primaries and the secondaries tipped with white; under surface of wings and the axillary plumes black.

“In selecting a specific name for this bird I have adopted that of H. albicollis, because it exactly expresses the feature which distinguishes it from the two others, namely, its having the neck entirely white. The same name was applied to a Stilt-Plover by Vieillot, but this has proved to be only a synonym of H. autumnalis and the title is therefore free again.

“The series of specimens under consideration is unfortunately very deficient in examples killed in winter, and the examination of the subject therefore has not been as complete or exhaustive as I would wish; but two points at any rate have been gained, namely the elimination from our list of Himantopus spicatus (which proves to be no species at all) and the placing on record of a hitherto undescribed form—the White-necked Stilt—which, so far as our present evidence goes, is a good and valid species. To my mind it is perfectly clear that it is either H. novæ zealandiæ in the mature winter plumage, hitherto unknown, or it is a distinct species; and if Dr. Barker’s specimen is rightly labelled as killed in summer, that fact alone is sufficient to disprove the former assumption.”

The late Dr. Jerdon wrote thus (Ibis, 1865, p. 35) of Himantopus leucocephalus:—“Examples of this bird quite similar to those figured in the ‘Birds of Australia,’ and to others which I have seen from this region, are not unfrequently obtainable in Lower Bengal in the same flocks with the common H. candidus (seu melanopterus). Great numbers of Longshanks are brought to the Calcutta provision-bazaar, often several dozens of them of a morning, during the season of their stay. Of these the great majority have a sooty-brown occiput, which changes to black at the approach of the breeding-season; but occasionally one then occurs with a purely white head and neck, or with more or less black down the nape, sometimes a mere trace of it, and sometimes the black nape is well developed (though never to the extent that is constant in the American species), and this may or may not be accompanied by the black occiput. I have also seen purely white-headed and white-naped specimens from Egypt, and one male from that country with just an indication of the dark nape; there is one with black nape and occiput among the British-killed specimens in the British Museum, and I have seen others like it from Europe and North Africa. Whether the leucocephalus type be constant in Australia remains to be ascertained; and the most likely explanation of this extraordinary and anomalous variation is, that differentiated races of this bird have more or less commingled. Most assuredly it can neither be referred to difference of age nor of season.”

Whether this interbreeding has actually occurred in New Zealand I am not in a position to say; but it may be well to remember that instances of apparent hybridism between the Black and Pied Oyster-catchers (quite a parallel case) are not uncommon. In January, 1886, I saw on the ocean-beach between Whakatane and Matata, a beautiful Pied Oyster-catcher paired with a perfectly black one. The nesting-season was far advanced and these birds were without doubt breeding together.