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A History of the Birds of New Zealand.

Dysporus Serrator. — (Australian Gannet.)

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Dysporus Serrator.
(Australian Gannet.)

  • Sula australis, Gould, P. Z. S. 1840, p. 177 (nec Steph.).

  • Sula serrator, Gray, Voy. Ereb. and Terror, Birds, p. 19 (1844).

  • Dysporus serrator, Finsch, J. f. O. 1867, p. 339.

  • Sula serrator, Buller, Birds of New Zealand, 1st ed. p. 323 (1873).

Native names.—Takapu, Takupu, and Toroa-haoika.

Ad. albus: pileo et collo postico clarè ochrascenti-fulvis: remigibus brunnescenti-nigris, scapis flavicantibus, versus apicem brunneis, secundariis intimis albis dorso concoloribus: caudâ albâ, rectricibus quatuor centralibus brunneis, ad basin albis: rostro saturatè cano: regione ophthalmicâ nudâ cyanescenti-canâ: plagâ nudâ ad basin rostri et fasciâ gulari nudâ nigricanti-canis: pedibus saturatè brunneis, tarso et pedibus anticè viridibus: iride pallidè argentescenti-brunneâ.

Adult. General plumage snowy white; the crown of the head and back of the neck deep sienna-yellow; the primaries, secondaries, and four central tail-feathers brownish black, with white shafts darkening towards the tips. Irides pale silvery brown; bill dark pearl-grey; bare space surrounding the eyes bluish grey; bare skin at the base of the beak and down the centre of the throat blackish grey; legs and feet dark brown, with a broad line of bright apple-green down the front of the tarsus and continued on the toes. Total length 35 inches; extent of wings 70; wing, from flexure, 19; tail 10; bill, along the ridge 3·5, along the edge of lower mandible 4; tarsus 2; middle toe and claw 3·75.

Young. Upper surface dark slaty grey, each feather with a rounded spot of white near the tip; the plumage of the forehead and vertex darker than the rest of the head, this shade running off into a point on the crown; under surface white, more or less ma ked on the fore neck and breast with sooty grey. The white spots are most distinct on the wing-coverts, scapulars, and feathers of the back and rump. The eyelids are dull grey, and have not that beautiful blue tint which adorns the fully matured bird; nor is the green rib on the tarsi and toes so conspicuous, for, although present, it is rather of a dull yellowish colour.

Younger state. There is a somewhat younger bird in my collection which has the white down still adhering to the vertex, nape, and hind neck. It differs in having the white spots on the upper surface, and particularly on the shoulders, larger and more conspicuous; also more white on the crown, with a few crescentic grey markings on the breast.

Progress towards maturity. A young bird, in the condition of plumage described above, was brought by me to England and presented (with other birds) to the Zoological Society. It was lodged in the Gardens at the end of April, and during several successive visits, extending over the following six months, I was able to mark the changes of plumage as the bird advanced towards maturity.

By the middle of July the spots on the upper surface had considerably diminished, being reduced on the back and wing-coverts to mere shaft-points. This change was not, however, due to the moulting of the feathers, but to the wearing away of the extremities, the shaft-tips being almost denuded. The dark markings on the head and neck had also undergone a change; but this was evidently the result of a new growth, for on the nape and hind neck the white now predominated, and was already assuming a yellow tinge. The spotted character was, however, still conspicuous on the wing-coverts, back, and rump. The tail-feathers were much page 178 worn and broken, probably the result of captivity. The facial membrane was nearly as blue as in the adult, but the lines on the tarsi and toes were of a much paler green; irides as in the adult.

By the end of October the head, neck, and underparts had assumed the plumage of the adult. The shoulders, back, and upper surface of wings were blackish brown, irregularly marked or variegated with white, all the new feathers being pure white, this transitional plumage having a very pretty effect. The white tips had disappeared from the scapulars, and were much worn and denuded on the wing-coverts; but the spots were still visible on the back and rump.

Nestling. Covered with thick woolly down of the purest white; forehead and cheeks denuded and of a yellowish colour. The woolly covering stands up and over the crown, giving the bird a peculiar “judicial look” which is very comical; bill black, with greyish tip to both mandibles; legs pale brown, with visible lines of paler brown along the tarsi and toes. The wing-feathers, which are the first to appear above the down, are black with white tips.

Remarks. The form of this bird is specially adapted to its plunging-habits, the body being very elongated and compressed on the sides, the neck long and powerful, and the head wedge-shaped in front, with a flattened crown. The throat is capable of great dilatation; and the bill, which is longer than the head and strongly formed, has a peculiar hinge-like development, the purpose of which is very obvious; on each side of the rounded culmen there is a deep longitudinal furrow, which forks laterally about an inch from the tip; below this the sides of the upper mandible are slightly convex, and towards the base there is a jointed notch, which, being elastic, adds considerably to the expansive power of the bill as a means of seizure. A bare membrane, extending from the base of the upper mandible, occupies the lores, turns sharply round the eyes, and ends in a narrow process about an inch in length and in a line with the gape; a similar membrane covers the throat, and passing down the middle of the gular pouch, terminates acutely. The tongue is rudimentary, being only a quarter of an inch in length, and free at both extremities. The nasal apertures are extremely small. The feet are strong, the toes webbed to their extremities, the claws short and convex, the middle one being flat and pectinate on its inner edge. The tarsi and toes are armed anteriorly with a line of soft acutella, which differ in colour from the surrounding parts. The total weight of the bird as only 3 lb.

Obs. The first moult would seem to take place before the young birds leave the breeding-ground, inasmuch as the spotted plumage is never met with at sea.

The Gannet is comparatively common on our coasts, and, during tempestuous weather, enters the bays and harbours in quest of its food.

It is a powerful flier; and it is very interesting to watch it while in pursuit of its finny prey: poising its body for an instant in mid-air, it plunges headlong into the sea, with a velocity that makes the spray rise several feet, entirely disappearing under the surface for some seconds, and then springing upwards with the buoyancy of a cork; after which it rests on the water for several minutes, and then takes wing again, to renew the feat.

In stormy weather it frequents our bays and harbours, being able to continue there its fishing-operations in spite of the weather. When the proverbial S.E. gale is blowing at Wellington, a few of them are always to be seen on the wing, coursing up and down the harbour, and a few amidst the shipping, sometimes mounting high, and ever and anon plunging under water. From the ocean-beach I have watched them, for hours together, when the sea was calm, foraging in pairs, crossing and recrossing each other’s line of flight with untiring industry and occasionally resting for a few minutes on the placid surface.

On the Whangarei river, several miles from the sea, I saw on one occasion several of these birds flying low over the quiet waters, and occasionally rising high in the air as if to reconnoitre; but their appearance at this distance from the sea is very unusual.

In dull murky weather the snow-white plumage of this bird, rendered more striking by the black page 179 extremities of the expanded wings, makes it a very conspicuous object as it sails majestically overhead or scans the surface of the rippling waves.

It is a curious circumstance, and perfectly well attested, that shortly before the terrific Tarawera eruption in 1886 the Gannets suddenly disappeared from White Island and from all their other resorts in the Bay of Plenty*.

On one occasion, when riding down the coast between Manawatu and Otaki, I came suddenly upon a Gannet asleep on the smooth sandy beach, and, dismounting from my horse, I succeeded in taking it before it awoke. It was a beautiful specimen, in full feather, and apparently quite healthy; but it was probably worn out by fatigue and hunger, after a stormy day at sea. The description at the head of this article was taken from this particular bird, which is now in the Colonial Museum.

It is a fact, although I was myself for a long time sceptical about it, that the Gannet cannot rise off a plane surface. On the ground it is quite helpless; and it can only mount in the air by getting on to an incline and then starting outwards.

When not fishing it generally flies pretty close to the water in a very direct course and with rapid and regular strokes of its narrow but powerful wings. The black pinions have a pretty effect by contrast with the pure white plumage of the body as the bird is thus seen skimming along the surface of the “dark blue wave.” Occasionally, however, it rises higher and sometimes forms a striking object in the sky. For instance, I find this passing note in my journal:—“The shores of Cook’s Strait, as we approach Queen Charlotte Sound, are bold and mountainous. As we proceed on our voyage, noble vistas open themselves to view, presenting wild and varied scenery and disclosing in the remote background towering peaks all shrouded in vapoury clouds. As we stand gazing at the ever-changing picture an object appears far away in the distance, held against the murky wall of cloud and mountain beyond like a boy’s kite sailing against the scud, and ever and anon glistening with pearly whiteness in the uncertain light. That object is a Gannet. Tired of fishing, he has mounted on his strong pinion and is now poising himself in mid-air and surveying far below him the troubled waters in which he loves to plunge.”

The Maoris manifest great admiration for the Gannet, because of its spirit and dash in catching fish; and this bird naturally takes a prominent place in the ancient story recounting a trial of strength between the birds of the sea and those inhabiting the land. (See page 148.)

I had a young bird brought to me towards the end of February; it was of full size, but in the immature plumage, looking very handsome in its spotted dress. I was staying at the time at the Wellington Club, and the bird was confined in a back yard, from which it made its escape several times in a very clever manner, and was always found skulking among the vegetation on the surrounding hills. It lived almost exclusively on fish, and had so voracious an appetite that I have known it to swallow as many as twenty-seven herrings in the course of a day. It never exhibited a spark of gratitude for this liberal supply of food, but would, on every occasion, attack its keeper’s hands in the fiercest manner, uttering at the same time a peculiar guttural sound as if choking. I succeeded in

* A newspaper correspondent thus refers to this singular coincidence:—” The ‘Hinemoa’ left Wellington for Tauranga on the night after the now famous eruptions at the Hot Lakes. She carried Dr. Hector, Major Mair, and others (including myself), who were hound for the scene of the disturbance. Nothing more uncommon than a heavy sea is to be recorded on the passage to White Island. Captain Fairchild ran in close to the island, but there was no sign of any recent disturbance, although the captain thought that the lake was throwing off more steam than usual, and that a mound which had latterly appeared in the lake had disappeared. The Gannets, however, which, to use the skipper’s description, were formerly so thick upon certain points ‘that you could not stick another Gannet in,’ left the island altogether some time before the eruption and have not returned, and I venture to recommend their unanimity to the notice of the numerous scientists, who will, no doubt, explain in full the why and the wherefore. Shortly after leaving White Island we encountered a vile sulphurous smell, which came in company with a thick fog off the land. A little more than an hour’s running took us through the fog, which left an impalpable dust upon everything on deck, and formed a peculiar froth upon the sea.”

page 180 bringing this bird to England in one of the New Shipping Company’s steamers, having been able to lay up a sufficient supply of fresh fish for the voyage in the ship’s freezing-chamber. On arrival I presented it, as already mentioned, to the Zoological Society, and there it developed the mature livery, sharing for a long time, with numerous other waterfowl, the pond-enclosure near the Eastern Aviary, and attracting the notice of visitors by the eager manner in which it followed the keeper about the ground at feeding-time.

Of the Australian Gannet the Earl of Pembroke writes* in the following spirited terms:—

“The splendid yellow-headed species which is common in the South Pacific is, I think, the finest of all fishing-birds from John o’ Groats to the Chatham Islands…… Soaring high he marks his prey beneath him, and shutting up his wings (like a Wood-Pigeon darting into cover) he plunges downwards with a splash that makes one’s head ache to look at, and after a semicircular dive of five or six yards, he emerges, sneezing and flapping, with his prey safely lodged in his throat. I have seen a good deal of Gannet-life, both domestic and public. On Nepean and Phillip Islands, in the Norfolk-Island group, I used to find the fond mother sitting affectionately by the side of the snowwhite fluff she called her child (paterfamilias having made himself scarce long before we reached the party) till I was within two or three yards of her, when she solemnly disgorged the two fish she had been cooking in her throat for her darling’s supper, and followed her mate’s example. These two fish on Nepean Island were nearly always a species of anchovy with the brown line of flesh, or fish, strongly marked; they were closely pressed together, and had evidently undergone a process of maceration if not of digestion. The New-Zealand Sula, like his Maori fellow-countryman, is of a most war-like nature, and fights fiercely for the sanctity of his nursery. I once saw the most stout-hearted of British skippers fairly driven off a rookery of them with his breeks in rags and tatters and his legs in holes, positively obliged to retreat and arm himself with a big stick before he could make his ground good. Even after the old birds were driven off, we had to walk warily amongst the sharp-billed Powder-puffs, as they never missed a chance of giving us a sharp prod if we came within their reach.”

Colonel Haultain informs me that on the occasion of a visit to White Island, in the Bay of Plenty, on Christmas day, he found thousands of young Gannets there. They were clothed in down, and were packed so closely together, that it was almost impossible to distinguish the occupant of any single nest. The old birds manifested no fear at the presence of man, and, where they were sitting on their eggs, required to be fairly pushed off before they would quit the nest. On being thus disturbed, or when fighting with one another, they utter a gurgling cry, like ko-wack, ko-wack, but habitually they are silent. It may be here mentioned that White Island is the top of a submerged volcanic cone, in the centre of which there is a deep lake of hot water, like a vast cauldron, constantly emitting steam, with occasional outbursts of boiling water rising to the height of several hundred feet. In the vicinity of this lake there are numerous round holes, in which boiling mud is kept in violent agitation; and the surface of the ground round these geysers is covered with great masses of crystallized sulphur, deposited by the heated vapours. Altogether the island is a very remarkable geological curiosity; and, considering its normal heat and the sulphurous state of its atmosphere, it seems a singular spot to be chosen as a nesting-ground.

Off the Kawhia shore, on the opposite or west coast (about halfway between Manukau and Taranaki), there is a bare rock, known to sailors as Gannet Island, where another extensive breeding-place exists. My son Percy visited this place in December 1883, in the Government steamboat ‘Hinemoa,’ but owing to the heavy sea he was unable to land. Passing, however, close alongside, he was able to make some observations, of which he has furnished the following note:—

* ‘South-Sea Bubbles,’ by the Earl and the Doctor, p. 65.

page 181

“The island comprises about six acres of rock, without to all appearance a blade of vegetation upon it, and is situated about thirteen miles abreast of Kawhia. It forms a gentle slope upwards from the sea, with a sheer precipice on the other side. On the slope a space of about three acres in extent was literally one mass of Gannets, there being tens of thousands. Captain Fairchild, who has visited the island on many occasions, says that he found an almost incredible number breeding there, the separate nests being indicated by a few loose feathers placed on the guano-deposits in every available spot. Each nest contained only a single egg, and there were no idle mates, the male and female occupying nests side by side. He states that this bird breeds twice in the season—first in September and again in February. Both sexes incubate, and at one and the same time; for every Gannet on the island was found sitting, and so close together that to walk amongst them was almost impossible. At the second breeding-time, in February, a young bird of the former brood, easily distinguished by its spotted plumage, is invariably found squatting alongside of the incubator. He has often watched the old birds bringing food to the nest. They come in from the sea with their pouched throats quite full of small fish, which they forthwith disgorge and divide between the young ones. The operation is a very droll one, and may be watched at a distance of only a few yards from the nest.”

Captain Fairchild has himself furnished me with the following interesting account of their breeding-habits:—

“The habits of the Gannet are so very strange that it may interest you if I give the results of my own experience with these birds. So far as I am aware, their only breeding-places off the coast of New Zealand are on Gannet Island, lying to the east, on some small islands in the Hauraki Gulf, near Coromandel and near to the Great Barrier, and on White Island in the Bay of Plenty. At all these places the birds congregate in great numbers. They commence laying about the 18th September, and it takes about thirty-three days to hatch out the young. The female lays two eggs; she keeps one and the male bird takes charge of the other, and each one hatches its own and afterwards looks after the wants of the young one. About the 1st February the same thing is repeated. The second hatching takes place about the first week in March. I hardly think that there can possibly be a mistake in this, as I have carefully watched the habits of these birds during the last twenty years, whenever an opportunity offered.”

There are evidently two broods in a season, for Captain Fairchild assures me that in every instance—and he examined hundreds of nests—where the old bird was covering an egg or a chick a well-grown young one, in spotted plumage, was sitting alongside, resting its beak on the parent’s shoulder, and on the least provocation showing fight in defence of the nursery. The old birds obstinately refused to quit their nests even when hustled and kicked with the foot; and when thus molested, fought viciously, striking at the intruder with their powerful bills, and inflicting sharp cuts on the hand if incautiously placed too near. On his return from one of his annual cruises among the islands lying off New Zealand, he sent me a whole basketful of the eggs of this fine Gannet. This was about the first week in February, and as most of the eggs contained a well-advanced embryo, this would indicate a comparatively early date for the second brood. They varied somewhat in size, but an ordinary example measured 3 inches in length by 1·8 in breadth. They were, for the most part, very elliptical in form, and of a pale greenish colour, covered over with a chalky incrustation and much soiled.

The eggs when taken from the nest are soiled and begrimed with dirt from the bird’s feet or from contact with the ground, having then a dark brown colour. On being cleaned by scrubbing with a wet brush, they present a chalky surface, often much scratched by the action of the bird’s feet; and on this being scraped off the shell becomes dull bluish white, which changes to a lovely pale blue tint on the inner surface.