(2194) Oceanites oceanicus oceanicus.
Wilson's Stormy. Petrel.
Procellaria oceanica Kuhl., Beitr, Anat., ii, p. 136, pl. x (1820) (South Atlantic Ocean;; Blanf. & Oates, iv, p. 354.
Vernacular names. None recorded.
Description. Upper tail-coverts, bases of outer tail-feathers and sides of flanks from vent pure white, greater secondary coverts grey with white tips; remainder of plumage sooty-brown; the primaries almost black with paler inner webs.
Colours of soft parts. Iris dark brown to black; bill, legs and feet black, the centre of the webs yellowish.
Measurements. Wing 140 to 157 mm.; tail 72 to 84 mm. tarsus about 32 to 36 mm.; culmen 12 to 14 mm.
Distribution. South Atlantic and Indian Oceans. Gumming obtained two specimens at Omara in the Persian Gulf and Butler obtained a third off the Mekran coast.
Nidification. This little Petrel breeds in great numbers on Laurie Island and other islands in the South Orkneys as well as in some of the more Southern islands. No nest is made, the single egg being deposited in a hollow under a rock, in narrow clefts and crevices in the face of a cliff and sometimes under stones, forming part of the debris at the foot of the cliffs. Often they are placed so far inside the crevices that it is impossible to get them out; at other times the face of the cliff is so crumbling and dangerous that it cannot be climbed, with the result that, though numerous nests may be four d, very few eggs are taken. The birds sit very close and have to be hauled out of the nesting-places by force, whilst all the time they give vent to a low whistle, repeated every few seconds. The hole selected for the egg may be on the flat shore or at a height of two or three hundred feet up a cliff.
The egg is pure white, though sometimes much stained, the only markings consisting of a ring of faint reddish freckles round the larger end. Eighteen eggs measured by Eagle-Clarke and myself average 33.6 x 23.2 mm.: maxima 36.0 x 24.0 mm.; minima 31.8 x 23.4 and 32.6 x 21.8 mm. In shape they are almost elliptical and the texture is coarse and rather rough but very fragile. Most eggs are laid in January, a few as late as March. When the birds are interfered with on the nest they emit an evil-smelling oily fluid through the mouth and nostrils.
Habits. Like other Petrels this bird is very local in its breeding-haunts, a great wanderer when the breeding-season is over. They are to be seen but seldom by day anywhere near land, even when breeding. At dawn they may be observed as they leave for the sea and at night, from 7 p.m. to 11 p.m., they fly backwards and forwards about the cliff in great numbers. In addition to their whistling notes these Petrels have a harsh, screaming chuckle. They feed on surface mollusca, animalculae and other surface-matter. In appearance they are extremely fragile but with their wonderful powers of flight they seem at home in the wildest storms, whether on the wing or swimming lightly poised on the crest of some huge wave.