• Gavia pomare, Bruch, J. f. Orn. 1855, p. 285 (not G. pomarre of 1853).

• Bruchigavia melanorhyncha, Buller, Ibis, 1869, p. 43.

• Larus (Bruchigavia) melanorhynchus, Finsch, tom. cit. p. 381.

• Larus bulleri, Hutton, Cat. Birds of N. Z. 1871, p. 41.

• Larus bulleri, Potts, Ibis, 1872, p. 38.

Native name.—Tarapunga.

Ad. suprà dilutissimè cinereus: pileo cum collo postico et interscapulio, dorso postico uropygio et corpore subtùs toto, albis: plagâ nuchali indistinctâ bruuneâ: tectricibus alarum dorso concoloribus, exterioribus et alâ spuriâ purè albis: remigibus dilutissimè cinereis dorso concoloribus, apicem versùs albis, primariis albis, pogoniis ambobus et apice pennarum plus minusve latè nigro marginatis, hâc albo terminatâ: caudâ omniò albâ: rostro nigro: pedibus nigricanti-brunneis: iride argenteo-albâ.

Juv. dorso et scapularibus obscurè brunneo notatis, plumis albo terminatis subterminaliter grisescenti-brunneo fasciatis: tectricibus alarum medianis grisescenti-brunneis albido marginatis: secundariis intimis medialiter distinctè brunneo lavatis.

Adult. General plumage pure white; back, scapulars, and upper surface of wings delicate ash-grey; breast and sides of the body suffused with a beautiful rosy blush, which fades after death, or entirely disappears. The primary quills are white, eccentrically varied with black; the first primary is narrowly margined on its outer and marked diagonally on its inner web, and tipped with black; on the next the black increases, and forms a broad subterminal bar, which enlarges on the two succeeding ones, and decreases on the fifth; the sixth is ashy, with merely a subterminal interrupted bar of black. Irides silvery white; bill black, sometimes tinged with red towards the base; legs and feet blackish brown. Total length 15 inches; extent of wings 35; wing, from flexure, 11·75; tail 4·5; bill, along the ridge 1·5, along the edge of lower mandible 2; bare tibia ·75; tarsus 1·5; middle toe and claw 1·5; hind toe and claw ·3.

Young. Has the plumage of the back and mantle and the scapulars obscurely spotted with brown, each feather having a white tip bounded below by an irregular spot of greyish brown; the first two primaries black, with a longitudinal oar-shaped white mark covering both webs, the rest of the primaries white in their basal portion, then black, and with minute terminal spots of white; the median wing-coverts greyish brown with a whitish margin; the long inner secondaries largely marked in their central portion with greyish brown. In some examples there is a wash of brown on the crown. Bill black in its terminal portion, reddish brown towards the base; legs and feet dull reddish brown.

Obs. The extent of the black markings on the primaries is very variable; and in some examples the first quill is largely tipped with black. There appears to be a seasonal change in the colour of the bill and legs, the former becoming dull yellow, stained at the tips with brown, and the tarsi and toes changing to pale orange-red, with darker webs and black claws.

The Black-billed Gull was originally described by myself, as already cited, under the name of page break

BLACK-BILLED GULL.
LARUS BULLERI
RED - BILLED GULL.
LARUS SCOPULINUS
(TWO FIFTHS NATURAL SIZE)

page break page 59 Bruchigavia melanorhyncha^*; but as the retention of Bonaparte’s subdivision is considered undesirable, I must now follow other authors in referring both this and the preceding species to the larger and better-defined genus Larus. Finding that the above title had already been bestowed on another member of the genus, by Temminck, Professor Hutton did me the honour to associate my name with the present species, which was figured for the first time in my former edition.

Another well-known local naturalist, Mr. T. H. Potts, paid me a similar compliment in proposing the name of Larus bulleri for a yellow-billed Gull, which he considered distinct. In treating of the latter bird (Birds New Zeal. 1st ed. p. 277) I stated that, whilst expressing my acknowledgments, I was unable to recognize the supposed specific distinction. On a careful comparison of the two birds, I found that they corresponded exactly in size, in the form of the bill, and in the colours of the plumage, even the eccentric markings on the primary quills being the same in both. The only difference, therefore, was in the colour of the bill and legs; and such a distinction could not be accepted as having any specific value till it had been shown that the difference of colour was constant in both birds all the year round. As opposed to the latter view, I mentioned that in the autumn of 1871 I had shot a specimen, on the sand-banks at Hokitika, in which the bill was pale coral-red in its basal portion, and brownish black beyond the nostrils, indicating, as it appeared to me, a transition to the black bill characteristic of the full winter plumage. Dr. Finsch, to whom I had forwarded skins of both for examination, concurred in this opinion; but he also went further, and referred the species to Larus pomare of Bruch (supposed to be from the Society Islands), although he complained of the extreme confusion and insufficiency of all Bruch’s descriptions. While attaching great weight to the opinion of so careful an ornithologist as Dr. Finsch, I was unable to adopt his view in this case; for having visited the Museum at Mainz and examined the type of Larus pomarre for myself, I found that it had a more robust bill than our bird, and more black on the primaries; while the young, in addition to the spotted markings on the back and wings, which appear to be common to the whole group, had dark ear-coverts, and a brown terminal band across the tail.

Mr. Howard Saunders in his revision of the Larinæ (P. Z. S. 1878) has cleared up the confusion in the nomenclature of this species with Larus pomare. He states that during a recent visit to Bremen he went into the whole question with Dr. Finsch, who had previously studied the subject, and had made numerous and careful drawings of the primaries of Bruch’s types of L. pomre in the Mainz Museum, and of many other specimens. He gives figures of the three outer primaries of Larus bulleri, and says “I have examined the type of Bruch’s L. pomare of 1855, and it is undoubtedly of this species; but the type of his L. pomarre of 1853 is as certainly L. novæ-hollandiæ.” (See woodcuts on page 62.) This explanation puts the matter in a perfectly clear light; and both pomare (Bruch) and melanorhyncha (mihi) having been previously employed for other species, our Black-billed Gull must stand as Larus bulleri, Hutton, under which name it is again described and figured here. I have recently visited Mainz again, and verified for myself the above observations.

On the habits of this species, as observed by Mr. Travers on Lake Guyon, in the provincial district of Nelson, I have much pleasure in quoting the following account from that gentleman’s facile pen:—“The Black-billed Gull breeds on the main river-bed; and one or more pairs usually frequent page 60 the lake after the breeding-season is over. On one occasion a pair of these birds, having by some means or other lost their own brood, returned to the lake earlier than usual. I brought up a young bird belonging to another brood, and placed it on the lake; and the bereaved parents at once took to it, tending it with the greatest care and solicitude. It is extremely interesting to watch these birds in their ordinary search for food during windy weather. The prevalent winds blow either up or down the lake; and when seeking food, the birds soar against the wind along the margin of the lake on one side, until they reach its extremity, when they at once turn and run down before the wind to the other end, where they recommence their soaring flight. But the most singular circumstance is that in the main valley they pursue various species of moths, which occur in large numbers amongst the tussock grasses, and especially in sedgy patches occupied by standing water. I could not for some time make out the object of their peculiar flight; but a friend of mine (Mr. R. W. Fereday, of Christchurch), who was lately on a visit with me for the purpose of collecting the lepidoptera of the district, whilst pursuing a large moth, observed one of these Gulls swoop at and capture it. We then noticed that some five or six of the birds were busily engaged in feeding on the moths, pursuing them very much as other insectivorous birds would do. The birds which frequent the lake become very tame, one pair in particular readily taking a worm from my outstretched hand, and constantly coming close to the house for food. Nothing can exceed the pureness and delicacy of their plumage when in full feather. It is doubtful whether this kind ever visits the sea-coast.”

The specimens on which Mr. Potts founded his description of Larus bulleri were obtained near the mouth of the Waimakariri river; and, as already mentioned, I met with the same bird on the west coast. The Black-billed Gull is therefore not confined to the inland lakes, as was hitherto supposed, but also frequents the mouths of rivers and estuaries, where it appears to mingle freely with the flocks of Larus scopulinus, Sterna frontalis, and other birds having a community of interest. It is comparatively plentiful in Queen Charlotte’s Sound and at Nelson. I have met with it frequently in Wellington harbour, as well as in ports further north; but it is far less common than the Red-billed Gull, from which it is easily distinguished on the wing by the black extremities of the primaries. It seems to be less social in its habits than the last-named bird, for I have generally noticed it associating in pairs when not commingling with flocks of the other species on their common feeding-ground. On the wing it is more Tern-like than L. scopulinus, and is generally less approachable.

Like the preceding species, the Black-billed Gull deposits its eggs on the bare ground, its attempts at forming a nest being of the rudest kind, a few bents of grass or other dry materials loosely collected round the edges being deemed a sufficient preparation. There are two examples of the egg of this Gull in the Canterbury Museum, both very handsome in appearance, but differing entirely in the style and distribution of their colours. One of these is of a narrow ovoid form, measuring 2·15 inches in length by 1·65 in breadth; it is of a dull yellowish white or pale buff, covered with numerous spots and irregular markings of dark brown; these markings are more numerous towards the thicker end, forming a broad zone and displaying fantastic shapes not unlike some of the characters in the Chinese alphabet; and on one side of the egg, commencing at the smaller end, there is a large blotch of rich umber-brown, varied with a darker brown, and covering more than half its surface. The other example is somewhat smaller and more rounded in form; the ground-colour is a delicate greenish grey; about the middle of the egg there is a narrow belt of a brighter tint of green; near the thick end there is a broad dark zone formed of obscure inky blotches, varied with irregular markings of blackish brown; and over the entire surface there are small scattered spots and markings of a rich dark-brown colour. A specimen in my son’s collection, obtained at Preservation Inlet, measures 2·25 inches in length by 1·5 in breadth, being more elliptical in form than the eggs of Larus scopulinus. It is of a dark cream-colour, the surface covered with numerous irregular spots of purplish brown, some having the usual washed-out appearance, and ornamented with peculiar pencilled markings resembling Arabic characters, which form themselves into a broad zone near the larger end.