(2189) Phaethon rubricauda rubricauda.
The Red-tailed Tropic-bird.
Phaethon rubricauda Bodd., Tabl. Pl. Enl., p. 57 (1783) (Mauritius) Blanf. & Oates, iv, p. 250.
Vernacular names. None recorded.
Description. A patch from the gape up to the eye, narrowly over it and in a broader streak behind black; primaries black-shafted; inner secondaries with broad black centres and black shafts ; long attenuated portions of the central tail-feathers bright red with black shafts ; remainder of plumage white, more or less tinged with rosy.
Colours of soft parts. Iris brown; bill yellow or reddish-yellow to orange-red ; legs yellow, toes and webs black.
Measurements. Wing 330 to 339 mm.; tail 360 to 428 mm.; tarsus 30 to 33 mm.; culmen 66 to 69 mm.
Young birds are white, the upper parts barred with black; primaries white with broad black shaft-streaks ; outer secondaries white with black shafts, inner nearly all black; tail-feathers pure white with black shafts and black subapical spots, the central feathers also tipped with black.
Nestling in down pure white.
Distribution. Red Sea and Persian Gulf to Mauritius and Assumption Islands.
Nidification. Nothing recorded. Various other subspecies breed in vast numbers on some of the islands in the Austro-Malayan region, laying their eggs on shelves of rocks or cliffs or in crevices of the rocks. Two eggs of this species in my collection taken on an island near Mauritius measure 64.6 x 49.3 and 70.8 x 49.3 mm. respectively. One of them is deep brick-red throughout, the red speckling completely obliterating the ground-colour. The second egg has the ground-colour just visible, showing it to be a yellow-stone ; the whole surface is covered with tiny freckles of red and with secondary freckles of lilac, whilst there are also a few reddish-brown blotches and spots, mostly at the larger end. They were taken, slightly incubated, on the 16th of January.
Habits. Similar to those of the preceding species.