(2188) Phaethon indicus.
THE SHORT-TAILED TROPIC-BIRD.
Phaeton indicus Hume, Str. Feath., iv, p. 481 (1876) (Mekran). Phaethon indicus. Blanf. & Oates, iv, p. 349.
Vernacular names. None recorded.
Description. A black patch round the front of the eye and extending back over it as a supercilium to the nape ; nape, hind-neck, back to upper tail-coverts narrowly barred with black; primaries black with broad white inner webs; outer secondaries white with black shafts, the inner almost all black; least coverts next the body pure white, those next them black with narrow white fringes, greater and median pure white; axillaries black with broad white edges ; remainder of plumage white.
Colours of soft parts. Iris dark brown; bill orange-red to dusky red, the tip, edge of commissure and nareal groove blackish ; legs and feet yellow or yellowish-white, the anterior toes and webs between them black.
Measurements. Wing 2S1 to 301 mm.; tail 215 to 301 mm.; tarsus 25 to 28 mm.; culmen 55 to 60 mm.
Young birds are like the adult but sometimes have black spots on the crown.
" Young in first plumage like the adult but with black tips to the central tail-feathers." (Ticehurst).
Nestling in down greyish-white, rather darker on the occiput.
Distribution. Northern Indian Ocean to the Persian Gulf.
Nidification. This beautiful Tropic-bird breeds during April and the end of March on the islands of the Persian Gulf, laving a single egg on the hare rock with no nest but under the shelter of a ledge or in a crevice. In 1898 Irvine took an egg of a Tropic-bird, but did not obtain the parent and this he put down as Phaethon rubricauda, which, of course, it could not have been. Then in 1916 Pitman obtained an egg found in a wide crevice in a rock on a barren island in the Persian Gulf. This was supposed to be an egg casually laid by a passing Kite but is certainly an egg of this species. Finally Sir Percy Cox received two genuine eggs through La Personne taken on Nabi-u-tand Island at the head of the Gulf. This island, too, is a very barren, rocky spot and the eggs were both taken from ledges protected by overhanging rock. These three eggs vary greatly in colour. One is white, faintly smeared with pale reddish in a ring round the larger end, with a few scattered specks and small blotches elsewhere ; the second is white, richly blotched with blood-red-brown at the larger end and very sparsely elsewhere; the third is freckled all over with dark dull reddish-brown, the freckles coalescing to form a cap at the larger end. The three eggs measure 54.5 x 41.3, 58.1 X 42.3 and 64.0 x 48.1 mm. In shape all are broad blunt ovals, whilst the texture is hard but coarse and rather rough. The inner membrane is white with a faint yellow tinge.
Habits. Tropic-birds, except at their breeding-places, are seldom seen close to land, spending their whole time at sea and nearly all on the wing, though they can and do swim well and easily like a Gull. Sailors call them Bos'un Birds and they will follow ships for many miles and when tired will sometimes rest on masts. Their night is exceptionally easy and elegant and as they turn from side to side, their long tail stretched behind them, they form a very beautiful picture. Their only note seems to be a low, harsh croak. Their food consists of mollusca, fish and other sea-surface life. They do not dive for their food but, if this is very small, take it up in the bill or, if fish, seize it with the bill but, when scavenging behind a ship, they catch scraps with their feet like Gulls.