The remaining species, often called "Boobies," have the whole lower jaw and throat bare. Of these S. cyanops, common in the South Pacific and ranging through the intertropical seas to the Bahamas in summer, is white with sooty-brown remiges, the wing-coverts and the lateral portion of the tail being partly of the same colour; the bill is yellow, the feet are reddish, and the naked parts bluish. S. leucogaster, extending from tropical and sub-tropical America over the Pacific, Indian, and Atlantic Oceans,[[78]] has the upper parts and chest brown, the remaining lower surface, and occasionally the head and neck, white; the bill is yellow, the feet are greenish or yellowish, the bare skin is tinged with red or yellow. S. piscator, also of the intertropical seas, resembles S. bassana, but has slate-grey wing-quills, purplish-grey bill, reddish feet and naked parts. S. variegata, of the shores of Chili and Peru, is dark grey-brown with white head, neck, and under parts, and white markings above. S. abbotti, of Assumption Island, north of Madagascar, is allied to S. cyanops. In this Family the sexes are alike, while the young are usually dusky with white streaks and spots; but those of S. cyanops are white below, and those of S. leucogaster and S. piscator chiefly sooty-brown, with grey head, neck, and under surface in the latter. It apparently requires six years to attain the full adult plumage.
Gannets are oceanic birds, only frequenting the land in stormy weather; they traverse very great distances, and the northern species move southward in winter. The flight is easy and powerful, with alternate flapping and sailing motion, the head being carried in a line with the body and the feet drawn up. The food consists of surface-swimming fish, squids, and the like, while the young obtain their nutriment by thrusting their bills into those of the parents, though it is disgorged for them when newly hatched. The prey is chiefly captured by diving, the plunge being made with great velocity from a considerable height and the body being submerged for several seconds; on coming to the surface the bird generally remains quiescent for a short period before again taking to the air, but occasionally swims for a longer period. When diving the wings are kept open until the last moment, and are then quickly closed. Gannets find the same difficulty in rising from a level spot as do Tropic-birds, and are less prone to perch than many other sea-birds. The note is a hoarse reiterated sound or, less commonly, a plaintive cry, much noise being often made by the large colonies when breeding. The nest is a mass of sea-weed and grass, placed on a ledge of some high cliff, on the top of a stack, or even on a low tree; while the eggs–never more than two in number–are occasionally deposited on the bare sandy beach, and are greenish-blue, thickly coated with a white chalky substance, which soon becomes soiled. Incubation lasts about six weeks. The adults, especially in the case of the Boobies, are often absurdly fearless on land, while the female, when on the nest, grunts at an intruder, and pecks or bites sharply. They are frequently caught on shipboard by fixing bits of fish on floating pieces of wood, in which the beak is transfixed by the violence of the plunge; they do not, however, afford palatable food, though in Scotland the Solan Goose is half-roasted and so preserved for eating.
Fam. III. Phalacrocoracidae.–The genus Phalacrocorax includes the Cormorants and Shags, birds of similar coloration, which differ chiefly in the brilliancy of their metallic hues and the proportion of white to black or brown in the plumage, the following examples giving a fair idea of the whole.
Fig. 22.–Cormorant. Phalacrocorax carbo. × ⅛.
P. carbo, the Common Cormorant, with fourteen rectrices, has the head and neck glossy blue-black, interspersed with white hair-like feathers, the remaining upper parts bronzy-black, the throat white, the bill and feet grey-black. In spring a slight crest adorns the occiput and white patches appear on the thighs. In common with its congeners this species has naked lores, orbital and gular regions, which are here of a yellow colour, becoming redder below the eye; the iris is emerald-green. The skin of the throat is dilatable and forms a pouch for food. It breeds on most of the British coasts, except between the Humber and the Thames, and occasionally inland; while it ranges to Greenland northwards, and thence down the Atlantic to New Jersey in the west, and to North and even South Africa on the east, as well as through Europe and Asia. The Australian and New Zealand P. novae hollandiae is doubtfully distinct. P. dilophus, of which several forms occur on the shores and in the interior of North America as far south as Mexico, is not unlike P. carbo, but has a tuft of long narrow recurved plumes on each side of the crown in the nuptial dress, which are black, white, or particoloured according to the locality. The bare loral region and gular sac are orange, and no white is visible on the throat or flanks. The splendid P. pelagicus, on the contrary, has white flank-patches in addition to white filaments on the neck and rump, the head and neck are violet-black, and a bronzy-purple tinge extends thence to the wings, the naked areas being brownish-red. It ranges from Kamtschatka to Western Mexico, and even winters in North Japan. P. urile, of the extreme north of the Pacific, is very similar, but has the gular pouch bluish with red hinder margin, the lores, orbits, and an additional strip of bare skin on the forehead being orange. P. perspicillatus, of Bering Island, now considered extinct, is another close ally, in which the filamentous feathers are yellowish and the orbits white. P. graculus, the Green Cormorant or Shag, breeding in Britain chiefly on the western side, and occurring rarely on our inland waters, is found in many places along the coasts of West Europe to Morocco and the Mediterranean; it is dark green with black remiges and twelve black rectrices, and metallic hues on the head, neck, and under surface, the irides being green and the bill and feet black, as are the naked regions, which are spotted with yellow. In spring a recurved crest overhangs the forehead. P. lucidus, of South, East, and apparently West Africa, differs from the last in having a brown head and nape, and grey tints on the mantle and tail, while the chin and most of the lower parts are white. P. africanus occupies South and East Africa. P. varius, of New Zealand, is greenish-black above with grey middles to the dorsal feathers, white cheeks and under surface; the bill is horn-coloured, the feet black, the orbits bluish, the gular skin yellow, with an orange spot before each eye. P. carunculatus, of New Zealand, has, according to Sir W. L. Buller,[[79]] no crest and a white band on the back, but otherwise resembles the crested P. onslowi of the Chatham Islands, and P. imperialis of Chili and Patagonia,[[80]] two fine iridescent species with the under surface and an alar bar white, the bare papillose skin in front of the eyes, orange-red, and the bill and feet brownish. P. featherstoni of the Chatham Islands, which is remarkable for possessing both an occipital and a frontal crest, is greenish-black and brown above with white filoplumes on the nape, and greyish-white below; the beak being dark brown, the feet orange-yellow, and the naked parts bluish. Similar tufts are met with in P. punctatus of New Zealand, wherein the upper plumage is mainly brown with terminal black spots on the feathers, the thighs show a few white markings, and a broad white stripe reaches from above the eye down each side of the neck, where the coat is somewhat elongated and silky. P. pygmaeus, the Pigmy Cormorant, which breeds across South-East Europe and South Asia to Java and Borneo, as well as in North Africa, is greenish-black with greyer mantle, reddish-brown head and neck, and small white spots on the lower surface, the naked parts being black. The sexes in Phalacrocorax are alike, or nearly so. The young are browner above–with little of the characteristic gloss–and brown, or white mottled with brown below, the bill and irides often differing in colour from those of the adult.
The members of this family as a rule frequent salt water, yet not uncommonly breed on inland lakes and swamps, especially in the proximity of trees; they are often to be seen in companies, and are decidedly shy and cautious in most cases. The heavy flight is strong, steady, and rapid, bearing a certain resemblance to that of the Duck-tribe, while the birds experience considerable difficulty in starting, and laboriously flap their wings until fairly launched in the air, when they rise to some height, or skim the waves, as fancy dictates. They swim and dive to perfection, remaining a long time submerged, and indulging in many a turn and twist as they pursue their slippery prey, both wings and feet lending their aid to the performance. Ordinarily a spring precedes the plunge from the surface, but in presence of danger they disappear more quietly. Though the gait on land is an awkward waddle, Cormorants perch with ease on rocks, posts, and limbs of trees, where their upright posture gives them the appearance of black bottles or objects hung out to dry; they are stated, moreover, to be able to cling to the face of a cliff, and certainly can climb among thick vegetation, as in the case of P. pygmaeus. Not unfrequently they roost in trees, with the head drawn back upon the shoulders. The food, normally of fish, is varied by crustaceans, or even frogs and newts; the young are fed by regurgitation, and, when old enough, thrust their heads into their parents' bills to help themselves.[[81]] The note, comparatively seldom heard, is a harsh guttural croak, while the female hisses during incubation, in which she is said to be assisted by the male. The nest, placed in caves, on ledges of cliffs, tops of stacks, or low islands, and less commonly on trees, bushes or reeds, is a mass of sticks, grass, seaweed, rushes and the like, according to situation; the smaller species constructing a slighter platform when the trees are chosen, and a lining of green leaves being occasionally added. Early in spring colonies, often of very large dimensions, are formed by many–but not all–of the species for breeding purposes, the stench from the remains of decaying fish at such spots being decidedly unpleasant. Incubation lasts about four weeks. Cormorants were of old used in England for catching fish, and this has been a regular business from time immemorial in China and Japan; but with us it is a mere sport, the chief exponent of which is now Captain F. H. Salvin, whose chapters on "Fishing with Cormorants" will be read with pleasure by those interested in the subject.[[82]] The bird rises to the surface to swallow its prey, but a strap round the neck allows it to dispose of the smallest only of its captures, while it is forced by its master to disgorge the remainder before it is rewarded with a portion of the catch.
Plotus anhinga, the Snake-bird or Darter of tropical and sub-tropical America, ranging northwards to West Mexico and South Carolina, is glossy greenish-black with beautiful silvery-grey markings on the scapulars and wing-coverts, a broad brown tip to the tail, which becomes white terminally, and long whitish hair-like feathers on the sides of the occiput and neck, merging into a black mane on the nape. The filoplumes are absent in winter, and are inconspicuous in the female, which differs, moreover, in having a grey-buff head, neck, and breast, the latter being divided from the belly by a chestnut band. The young resemble the mother-bird, but are duller and lack the chestnut tint. The peculiar long thin neck and corrugated rectrices have been mentioned above; the plumage is unusually close, and is chiefly composed of small soft feathers of very uniform distribution; the lores, orbits, chin, and throat are naked, the two former being apparently greenish, and the latter, which is moderately dilatable, orange. The bill is olive above and yellow below, the feet mainly olive with yellow webs. Three other species are recognised, but the variability in the amount of rufous in all makes their validity somewhat questionable. They are P. novae hollandiae of Australia, New Zealand, and New Guinea, with a white stripe on the sides of the head and a white border to the gular sac; the almost identical P. melanogaster of the Indian Region, extending to Celebes; and P. levaillanti of the Ethiopian Region–described also from Antioch as P. chantrii–which has a rufous crown, buff throat, and chestnut greater wing-coverts.
Fig. 23.–Indian Darter. Plotus melanogaster. × ⅕. (From Nature.)