Gannet


From Encyclopedia Britannica (11th edition, 1910)

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Gannet (O.E. ganot) or Solan Goose,1 the Pelecanus bassanus of Linnaeus and the Sula bassana of modern ornithologists, a large sea-fowl long known as a numerous visitor, for the purpose of breeding, to the Bass Rock at the entrance of the Firth of Forth, and to certain other islands off the coast of Britain, of which four are in Scottish waters—namely, Ailsa Craig, at the mouth of the Firth of Clyde; the group known collectively as St Kilda; Suleskerry, some 40 m. north-east of the Butt of Lewis; and the Stack and Skerry, about the same distance westward of Stromness. It appears also to have two stations off the coast of Ireland, the Skellig Islands and the Stags of Broadhaven, and it resorts besides to Lundy Island in the Bristol Channel—its only English breeding-place. Farther to the northward its settlements are Myggenaes, the most westerly of the Faeroes, and various small islands off the coast of Iceland, of which the Vestmannaeyjar, the Reykjanes Fuglaskér and Grimsey are the chief. On the western side of the Atlantic it appears to have but five stations, one in the Bay of Fundy, and four rocks in the Gulf of St Lawrence. On all these seventeen places the bird arrives about the end of March or in April and departs in autumn when its young are ready to fly; but even during the breeding-season many of the adults may be seen on their fishing excursions at a vast distance from their home, while at other times of the year their range is greater still, for they not only frequent the North Sea and the English Channel, but stray to the Baltic, and, in winter, extend their flight to the Madeiras, while the members of the species of American birth traverse the ocean from the shores of Greenland to the Gulf of Mexico.

Gannet, or Solan Goose.

Apparently as bulky as a goose, and with longer wings and tail, the gannet weighs considerably less. The plumage of the adult is white, tinged on the head and neck with buff, while the outer edge and principal quills of the wings are black, and some bare spaces round the eyes and on the throat reveal a dark blue skin. The first plumage of the young is of a deep brown above, but paler beneath, and each feather is tipped with a triangular white spot. The nest is a shallow depression, either on the ground itself or on a pile of turf, grass and seaweed—which last is often conveyed from a great distance. The single egg it contains has a white shell of the same chalky character as a cormorant’s. The young are hatched blind and naked, but the slate-coloured skin with which their body is covered is soon clothed with white down, replaced in due time by true feathers of the dark colour already mentioned. The mature plumage is believed not to be attained for some three years. Towards the end of summer the majority of gannets, both old and young, leave the neighbourhood of their breeding-place, and, betaking themselves to the open sea, follow the shoals of herrings and other fishes (the presence of which they are most useful in indicating to fishermen) to a great distance from land. Their prey is almost invariably captured by plunging upon it from a height, and a company of gannets fishing presents a curious and interesting spectacle. Flying in a line, each bird, when it comes over the shoal, closes its wings and dashes perpendicularly into the waves, whence it emerges after a few seconds, and, shaking the water from its feathers, mounts in a wide curve, and orderly takes its place in the rear of the string, to repeat its headlong plunge so soon as it again finds itself above its prey.2

Structurally the gannet presents many points worthy of note, such as its closed nostrils, its aborted tongue, and its toes all connected by a web—characters which it possesses in common with most of the other members of the group of birds (Steganopodes) to which it belongs. But more remarkable still is the system of subcutaneous air-cells, some of large size, pervading almost the whole surface of the body, communicating with the lungs, and capable of being inflated or emptied at the will of the bird. This peculiarity has attracted the attention of several writers—Montagu, Sir R. Owen (Proc. Zool. Soc., 1831, p. 90), and Macgillivray.

In the southern hemisphere the gannet is represented by two nearly allied but somewhat smaller forms—one, Sula capensis, inhabiting the coast of South Africa, and the other, S. serrator, the Australian seas. Both much resemble the northern bird, but the former seems to have a permanently black tail, and the latter a tail the four middle feathers of which are blackish-brown with white shafts.

Apparently inseparable from the gannets generically are the smaller birds well known to sailors as boobies, from the extraordinary stupidity they commonly display. They differ, however, in having no median stripe of bare skin down the front of the throat; they almost invariably breed upon trees and are inhabitants of warmer climates. One of them, S. cyanops, when adult has much of the aspect of a gannet, but S. piscator is readily distinguishable by its red legs, and S. leucogaster by its upper plumage and neck of deep brown. These three are widely distributed within the tropics, and are in some places exceedingly abundant. The fourth, S. variegata, which seems to preserve throughout its life the spotted suit characteristic of the immature S. bassana, has a much more limited range, being as yet only known from the coast of Peru, where it is one of the birds which contribute to the formation of guano.

(A. N.)

1 The phrase ganotes bæð (gannet’s bath), a periphrasis for the sea, occurs in the Anglo-Saxon Chronicle, in reference to events which took place A.D. 975, as pointed out by Prof. Cunningham, whose learned treatise on this bird (Ibis, 1866, p. 1) nearly exhausts all that can be said of its history and habits. A few pages further on (p. 13) this writer remarks:—“The name gannet is intimately connected with our modern English gander, both words being modifications of the ancient British ‘gan’ or ‘gans,’ which is the same word as the modern German ‘Gans,’ which in its turn corresponds with the old High German ‘Kans,’ the Greek χήν, the Latin anser, and the Sanskrit ‘hansa,’ all of which possess the same signification, viz. a goose. The origin of the names solan or soland, sulan, sula and haf-sula, which are evidently all closely related, is not so obvious. Martin [Voy. St Kilda] informs us that ‘some imagine that the word solan comes from the Irish souler, corrupted and adapted to the Scottish language, qui oculis irretortis e longinquo respiciat praedam.’ The earlier writers in general derive the word from the Latin solea, in consequence of the bird’s supposed habit of hatching its egg with its foot; and in a note intercalated into Ray’s description of the solan goose in the edition of his Itineraries published by the Ray Society, and edited by Dr Lankester, we are told, though no authority for the statement is given, that ‘the gannet, Sula alba, should be written solent goose, i.e. a channel goose.’” Hereon an editorial note remarks that this last statement appears to have been a suggestion of Yarrell’s, and that it seems at least as possible that the “Solent” took its name from the bird.

2 The large number of gannets, and the vast quantity of fish they take, has been frequently animadverted upon, but the computations on this last point are perhaps fallacious. It seems to be certain that in former days fishes, and herrings in particular, were at least as plentiful as now, if not more so, notwithstanding that gannets were more numerous. Those frequenting the Bass were reckoned by Macgillivray at 20,000 in 1831, while in 1869 they were computed at 12,000, showing a decrease of two-fifths in 38 years. On Ailsa in 1869 there were supposed to be as many as on the Bass, but their number was estimated at 10,000 in 1877 (Report on the Herring Fisheries of Scotland, 1878, pp. xxv. and 171),—being a diminution of one-sixth in eight years, or nearly twice as great as on the Bass.