The soft, dense plumage shows various patterns of black, brown, grey, and white; the bill and feet may be black, brown, flesh- or horn-tinted, yellow, orange, or parti-coloured, but in Prion and Halobaena the latter are bluish. Light and dark phases are not uncommon, as in Fulmarus and Ossifraga; the sexes are invariably similar; and the nestlings, which long remain helpless, are clad in thick down of a black, brown, grey, or white hue, through which the feathers appear gradually. Some white Albatroses have intermediate dusky stages of plumage, and do not gain the adult coloration at once, as most of the Family seem to do.
Diomedea exulans is one of the largest birds that fly, exceeding a goose in size, while the smaller Petrels are hardly bigger than Finches. The range of the Order is world-wide, though a majority of species frequent the desolate tracts and islands of the southern oceans; but even Albatroses breed in the North Pacific.
Though the members of this Family can hardly be called gregarious, flocks of Shearwaters, Fulmars, and so forth are by no means an uncommon sight from shipboard, and settlements are formed in the breeding season, which is almost the only occasion on which they voluntarily seek dry land. Albatroses, Fulmars, the "Cape Pigeon" (Daption), and other allied forms are observed most commonly in the daytime, whereas those that nest under cover are to a great extent nocturnal during incubation, and are generally seen or heard after dusk. While the whole group is oceanic, there is a wide difference between the powerful Albatros and its smaller and weaker relations in that respect, the latter journeying but little from the immediate neighbourhood of their homes, and not accompanying ships for long distances in the same way as the former. In the larger species the flight is strong and graceful,[[64]] accompanied by circling, soaring, or sailing movements, the feet being extended below the tail; Shearwaters skim the waves in a curious twisting fashion, and the lesser Petrels flit with greater action of the wing close to the surface, upon which they paddle to assist themselves. The Diving Petrels–and their allies to a limited extent–plunge through or beneath the billows, while all species may be noticed at times resting or swimming upon the water. Equally at home in storm or calm, they pass the greater part of their lives upon the ocean, and it seems impossible to doubt the fact that they sleep there also. Great difficulty is experienced in rising from a level surface, whether it be the deck of a ship or a grassy flat; the birds scrambling along with flapping wings and occasional aid from the bill, until some slight declivity or broken edge enables them to obtain a start. When taken from a nest in a burrow, they either drop to the ground like stones, or flutter off in a dazed condition, which lasts for several seconds, and renders them absolutely helpless. The cry is said in various cases to resemble a bray, a croak, a harsh cackle, a diabolical scream, a puppy's whine, or a soft whistle, while the twittering or "singing" of Procellaria, Oceanodroma, and Oceanites in their holes is well known to those who have visited a Storm Petrel's colony. The food consists of fish, crustaceans, cephalopods and other molluscs, jellyfish, and the like, Albatroses and Fulmars being said to force other species to part with their booty after the manner of Skuas, or even to devour nestlings. Herbage is rarely found in the stomach, but blubber of dead animals and scraps thrown from shipboard are eagerly swallowed, so that many of the largest forms are captured by concealing a hook in a piece of pork and trailing it in the water on a cork, when the bait is often greedily contested by every individual in the vicinity. Albatroses and other members of the Family which will take food from the surface of the sea descend upon it with elevated wings, to rise again with the morsel obtained, or to float upon the waves while enjoying it; Shearwaters commonly dash down with considerable impetus, and disappear after their prey for the moment; while the Diving Petrels procure their nourishment at a much greater depth. When handled, and perhaps especially when taken from a nesting-hole, the birds bite severely, and eject a quantity of amber-coloured or greenish oil from the beak, followed as a rule by semi-digested food, the fluid possessing a strong smell of musk, which is also perceptible in the feathers and the eggs. The nest of the Albatros is usually a truncated cone or cylinder of mud, grass, leaves, and moss, with a slight depression on the top, colonies being formed on cliffs, rocky slopes, or bare hill-tops above the limit of trees; the Giant Petrel makes a similar structure at no great elevation; Shearwaters and their nearest allies collect a mass of grass and rubbish in a burrow scraped in a bank, among boulders, or in holes and crevices of rocks, accommodating themselves to little stone huts, provided by the fishermen, in the Canary and Salvage Islands.[[65]] Fulmars scrape a cup-shaped hollow on ledges of precipices, adding little or no lining, while most of the remaining forms utilise small burrows, or crannies among the scattered stones which collect upon the shores or at the base of cliffs. A single lack-lustre white egg is deposited, frequently marked with a ring of rusty spots towards the larger end, especially in the case of the lesser species. Adult and young Shearwaters are eaten by the natives of the Canaries, the islands of Scotland, Ireland, and elsewhere, Puffinus brevicauda being the "Mutton-bird" of Australia, and P. anglorum being termed "Fachach" in the Hebrides and North Ireland. In the case of Pelagodroma, we have positive evidence that both sexes incubate;[[66]] and before the eggs are laid the parents are not uncommonly found together in the hole when such a site is chosen. Incubation lasts from twenty-five to sixty days.
Sub-fam. 1. Diomedeinae.–This contains two genera, Phoebetria and Diomedea, of which the former has one member, P. fuliginosa, of a sooty grey colour, distinguished from its allies by the sulcated mandible and cuneate tail. It frequents the South Seas, while straying to Oregon, as does Diomedea culminata; and has similar manners to other Albatroses. Diomedea exulans, the Wandering Albatros, or "Cape Sheep," of the Southern Oceans generally, is white with narrow dusky undulations above and almost black wings; and particulars of the habits having been already given, it only remains to refer to the majestic flight, described by Professor Hutton as follows: "With outstretched, motionless wings he sails over the surface of the sea, now rising high in the air, now with a bold sweep, and wings inclined at an angle with the horizon, descending until the tip of the lower one all but touches the crests of the waves as he skims over them. Suddenly he sees something floating on the water and prepares to alight; but how changed he now is from the noble bird but a moment before, all grace and symmetry.
Fig. 18.–Wandering Albatros. Diomedea exulans. × ⅑.
He raises his wings, his head goes back, and his back goes in; down drop two enormous webbed feet straddled out to their full extent, and with a hoarse croak, between the cry of a Raven and that of a sheep, he falls 'souse' into the water. Here he is at home again, breasting the waves like a cork. Presently he stretches out his neck, and with great exertion of his wings runs along the top of the water for seventy or eighty yards, until, at last, having got sufficient impetus, he tucks up his legs, and is once more fairly launched in the air."[[67]] D. regia, of the New Zealand seas, has no undulations on the back; the similar D. chionoptera, of the Southern Indian Ocean, has nearly white wing-coverts; and D. albatrus, of the North Pacific, has buff crown and nape. Of the smaller forms, or Mollymauks (p. [65]), D. irrorata, of West Peru, is sooty-brown with plentiful white mottlings and white head; D. nigripes, of the North Pacific, is the same colour, but shews white only at the base of the tail and bill, and near the eye; D. immutabilis, found from Laysan to Japan, is darker, with white head, neck, rump, base of tail, and lower parts; D. melanophrys, of the southern oceans, which has occurred in California, and in summer in England as well as at the Faeroes,[[68]] is white, with a blackish band on each side of the eye, slaty back, brownish-black wings, and grey tail; D. bulleri, of the New Zealand seas, is greyish-brown, with white rump and lower surface, and ashy or whitish head; D. culminata and D. chlororhyncha, of the southern oceans, D. cauta of Tasmania, D. salvini of the New Zealand Seas, and D. layardi of those of the Cape, have similarly coloured plumage; the last five being distinguished by some writers as Thalassogeron, and having a strip of naked skin between the plates of the maxilla towards its base. D. bulleri has red, D. chlororhyncha flesh-coloured, and the others yellow feet; the amount of yellow on the bill varying with the species.
Sub-fam. 2. Oceanitinae.–The genera recognised are Cymodroma, Pealea, Pelagodroma, Garrodia, and Oceanites; they are sooty- or slaty-black birds, of small size, having in some cases the rump, under parts, nuchal collar, forehead, superciliary streaks, or margins to the feathers of the dorsal region white. Their range extends over different portions of the southern seas, whence Oceanites oceanicus, Wilson's Petrel, has strayed to Labrador and Great Britain, and Pelagodroma marina to the latter and Massachusetts, while breeding in the Salvage Islands south of Madeira and the Cape Verds. The habits do not seem to differ appreciably from those of the Storm-Petrel.[[69]]
Sub-fam. 3. Procellariinae.–As here arranged, this comprises three groups typified by the Fulmars, Shearwaters, and Storm-Petrels respectively. Of the first, Ossifraga gigantea, the Giant Petrel, or "Nelly" of the southern seas, recorded also from Oregon, is dark brown, often with white on the head when immature, and sometimes almost entirely white. Fulmarus glacialis of the North Atlantic, the Fulmar of St. Kilda, and the true Mollymauk of sailors, which is represented in the North Pacific by the barely separable F. glupischa and F. rodgersi, is bluish-grey with dusky quills, white head, neck, and lower parts; the dark phase being uniform dusky grey. It is smaller than Ossifraga, yet equal to a medium-sized Gull, though easily distinguished by its light gliding flight with little motion of the wings; in rough weather it skims very near the waves, while the croaking note is seldom heard. Daption capensis, the Cape-Pigeon, ranging from Ceylon and Peru throughout the southern oceans, is black and white above and nearly white below; it is well known as a constant companion of ships, especially off South Africa, hovering or swimming around, uttering its harsh cackle, or plunging into the water to fight for scraps thrown overboard. Halobaena caerulea, extending from lat. 40° to 60° S., is grey-blue above and white below, with a little white on the head, scapulars, and tail; the habits resembling those of Prion, a genus of four species, remarkable for the fringe of lamellae on the bill, and having blue-grey upper parts varied with black, white under parts and superciliary streak. These forms are found throughout the southern seas, while P. ariel has occurred in Madeira. P. desolatus, the Whale-bird of sailors, is frequently seen flitting round vessels, uttering its whistling or cooing note, or taking food from the water upon the wing; the slight nest is formed in an extremely small burrow.
Little object would be served by describing in detail the twenty members of Puffinus (Shearwater) or the thirty of Oestrelata, the main constituents of our second group of Procellariinae. The former are sooty-brown or greyish, commonly with white below, and in some cases with white or pale edges to the feathers above; all are much alike except the uniform species, but it should be carefully noted that Petrels are often best distinguished by the colour of the bill and feet. The habits of these birds, which are distributed throughout the greater part of the world, have been already sufficiently treated. P. anglorum, the "Manx" Shearwater, breeds along the west of Great Britain, in the Orkneys, Shetlands, and Ireland, P. major or gravis, P. griseus, P. obscurus, P. assimilis, and P. yelkouanus, the âme damnée of the Bosphorus, being occasional visitors to our shores. In Oestrelata the coloration is grey, brown, or blackish, with a decided tendency to lighter margins on the upper feathers, and in a few of the members more or less white on the tail, wing, or head; the under parts, moreover, being frequently white. The various forms reach from the southern temperate regions to Japan and also to Britain, where Oe. haesitata and Oe. brevipes have each been recorded once. The latter breeds on mountain-tops in islands, and of its other congeners some at least do likewise, many having an extremely limited range at all seasons.