Art.. VIII.—On some Birds from the Kermadec Islands.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 21, 1888, Unnumbered Page

Art.. VIII.—On some Birds from the Kermadec Islands. By T. F. Cheeseman, F.L.S. [Read before the Auckland Institute, 24th September, 1888.] In my paper on the flora and fauna of the Kermadec Islands, printed in the recently-issued volume of “Transactions of the New Zealand Institute,”* “Trans. N.Z. Inst.,” vol. xx., art. xxiii., pp. 163–5. I have given a list of the birds observed during my short stay in the group. Since then Captain Fairchild has made a second visit to the islands, and has obtained some additional specimens, which he has very kindly placed in my hands. Mr. Bell, the resident on Sunday Island, has also forwarded to the Museum a collection of birds' eggs, accompanied with some interesting particulars respecting several of the sea-birds which frequent the island for breeding purposes. From these sources of information I am now able to record the presence of two species new to the New Zealand fauna, and to prove that a third, hitherto only known as an occasional straggler in our waters, breeds regularly in the Kermadec group. 1. Sula cyanops, Sundevall (Masked Gannet). In my list I briefly alluded to the presence of a fine gannet differing from the species common all round the North Island in wanting the buff-coloured feathers on the head. From the deck of the “Stella” it was noticed to be breeding in some numbers on the top of Curtis Island, but, as bad weather compelled Captain Fairchild to put out to sea before an ascent of the cliffs could be made, I was unable to procure a specimen. During his last visit, however, Captain Fairchild was more fortunate. He reached the summit of the island, and, finding the birds breeding there as before, caused four of them to be taken off their nests and carried on board the steamer. Thanks to his care, all four reached Auckland alive. On examining them it was evident that the species was that known as the masked gannet (Sula cyanops), which has a wide range in tropical seas, but had not been previously found on the coast of New Zealand. As mentioned above, it is at once distinguished from our common gannet (Sula serrator) by the head and neck of the adult bird being perfectly white,

and presenting no trace of the beautiful buff-yellow so conspicuous in Sula serrator. It is also rather smaller, and the shape and colour of the bare skin at the base of the bill are different. In the masked gannet the bare skin extends a little beyond the corners of the mouth, and then crosses the throat in an almost straight line, while its colour in the adult bird is a deep blackish-blue. This dark colour contrasts vividly with the snow-white feathers of the head and neck, and is doubtless the reason why the bird has received the common name of the “masked gannet.” In Sula serrator the bare skin is continued under the throat for a considerable distance in the shape of a narrow triangular stripe, and its colour is a pale leaden-blue. Like our species, it forms no true nest. On Curtis Island its single egg was placed in a slight depression among the scanty tufts of short grass which form the chief vegetation on the top of the island. The females are quite exposed while sitting on the nest, and from their white plumage form very conspicuous objects; but, as they are strong and powerful birds, well able to defend themselves from all enemies, their exposed position is probably no real disadvantage to them. Few birds have a wider geographical range. Drs. Finsch and Hartlaub, in their well-known book on the avifauna of Central Polynesia, state that it has been found in the following localities: The Atlantic Ocean, near Ascension Island; the Red Sea; Cocos Island; the Straits of Sunda; Torres Straits and North Australia; Polynesia, from the Sandwich Islands southwards to Samoa, and westwards from the Paumotu group to the New Hebrides. It seems probable that it also exists on the coasts of both North and South America. 2. Gygis candida (Silky White Tern). While conversing with Mr. Bell respecting the birds of Sunday Island he alluded to a small white tern which visits the island every November to breed. From his description of the plumage, & c., and account of its breeding-habits, I concluded that it would probably prove to be this species. During the last breeding-season Mr. Bell made further notes on it, and has now sent me these, together with specimens of the egg. As his notes, and the shape, size, and colour of the egg agree exactly with the published accounts of Gygis candida, I have now no hesitation in considering it to be that species. The bird, which is a most beautiful one, is rather smaller than our common tern (Sterna frontalis). It has a slender body, long wings, and deeply-excised tail. The whole of the plumage is pure-white, and of silky softness. The bill is long and curved slightly upwards, dark-blue at the base, shading off into black at the tip. Its breeding-habits are peculiar. Mr.

Cheeseman.—On Birds from the Kermadec Islands. Bell writes, “It lays its solitary egg high up on the pohutukawa trees, on a horizontal branch not much thicker than a man's wrist. The bird sticks to the egg and keeps it in its place until it is hatched.” This statement is corroborated by what is known of its habits in some other localities. Mr. Cuming, the well-known conchologist, observed it on Elizabeth Island, and says, “It was breeding on a kind of pandanus, its single egg being deposited on the horizontal branches, in a depression which, although slight, was sufficient to retain it in position despite of the high winds and consequent oscillations to which it was subjected.” Mr. Cuming adds that the old birds were flying about in thousands like swarms of bees, and that he noticed several breeding on the same tree. Several young birds were observed lying dead on the ground, from which it appears that they frequently drop from their dangerous resting-place. However, it does not always breed on trees; for Dr. Graffe, a German collector, found it resting in hollows of the bare rock on one of the islands of the Phænix group. Gygis candida is found throughout the whole of Polynesia, along the Australian coasts northwards to Torres Straits, and from thence through the Malay Archipelago to India. It has also been recorded from the west coast of Africa. 3. Phaeton rubricauda, Bodd (Red-tailed Tropic Bird). This beautiful bird, so familiar to all voyagers in the warmer parts of Polynesia, has long been known to breed as near to New Zealand as Norfolk Island, and occasional stragglers are at long intervals captured by the Maoris residing near the North Cape, usually after a succession of heavy northerly gales. Few Europeans, however, have seen it in New Zealand waters, and the only specimen obtained, so far as I know, is one shot by Mr. Henry Mair near the Three Kings Islands, and now in the possession of Sir Walter Buller. When at the Kermadec Islands last year Mr. Bell informed me that the tropic bird breeds regularly on Sunday Island, arriving in October and remaining until the close of summer. I therefore inserted the species in my list on his authority. I have now received from him several roughly-prepared skins and some eggs which prove that it has been correctly identified. Its appearance, habits, and geographical distribution are too well known to require mention here. The following record of the temperature at Sunday Island in 1887–88 has been made by Mr. Bell, and forwarded by him to Mr. Percy Smith, Assistant Surveyor-General. As no meteorological observations of any kind have been pre-

viously taken in the group, it is perhaps worth insertion here:— I. Mean temperature in the shade, taken from daily observations made at 9 a.m.:— ° January 77.4 February 74.6 March 74.9 April 69.4 May 68.1 June 65.0 July 62.1 August 64.0 September 68.5 October 68.3 November 72.6 December 75.3 Mean for the year, 70°. II. Occasional readings of the thermometer taken at noon:— Shade. Sun. Jan. 3 85 107 " 5 87 110 " 15 88 104 " 16 89 Cloudy " 17 91 110 " 18 91 110 " 19 94 111 " 20 94 112 " 22 95 120 " 25 90 114 " 31 88 Cloudy Feb. 9 85 100 " 11 90 108 " 16 87 104 " 27 86 102 Mar. 16 85 101 " 20 87 100 June 14 70 90 " 22 70 89 July 1 69 87 " 29 67 90 Nov. 14 84 94 " 22 94 104 Dec. 4 85 102 " 12 83 106 " 19 87 102 " 24 84 100 " 28 89 100