TERN (Norse taerne, tenne or tende; Swedish tärna; Dutch Stern[1]), the name now applied generally to a group of sea-birds, the sub-family Sterninae of the gulls or Laridae, but, according to P. J. Selby, properly belonging, at least in the Farne Islands, to the species known by the book-name of Sandwich tern, all the others being those called sea-swallows—a name still most commonly given to the whole group throughout Britain from their long wings, forked tail and marine habit. In F. Willoughby's Ornithologia (1676), however, the word tern is used for more than one species, and, though it does not appear in the older English dictionaries, it may well have been from early times as general a name as it is now.

Setting aside those which are but occasional visitors to the British Islands, six species of terns may be regarded as indigenous, though of them one has ceased from ordinarily breeding in the United Kingdom, while a second has become so rare and regularly appears in so few places that mention of them must for prudence sake be avoided. This last is the beautiful roseate tern, Sterna dougalli; the other is the black tern, Hydrochelidon nigra, belonging to a genus in which the toes are only half-webbed, of small size and dark leaden-grey plumage. It is without doubt the Sterna of Turner, and in former days was abundant in many parts of the fen country,[2] to say nothing of other districts. Though nearly all its ancient abodes have been drained, and for its purposes sterilized these many years past, not a spring comes but it shows itself in small companies in the eastern counties of England, evidently seeking a breeding-place. All around the coast the diminution in the numbers of the remaining species of terns is no less deplorable than demonstrable.

The Sandwich tern, S. cantiaca—named from the place of its discovery, though it has long since ceased to inhabit that neighbourhood—is the largest of the British species, equalling in size the smaller gulls and having a dark-coloured bill tipped with yellow, and dark legs. Through persecution it has been exterminated in all its southern haunts, and is become much scarcer in those to which it still resorts. It was, however, never so abundant as its smaller congeners, the so-called common and the arctic tern—two species that are so nearly alike as to be beyond discrimination on the wing by an ordinary observer, and even in the hand require a somewhat close examination.[3] The former of these has the more southern range, and often affects inland situations, while the latter, though by no means limited to the Arctic circle, is widely distributed over the north and mostly resorts to the sea-coast. Yet there are localities where, as on the Farne Islands, both meet and breed, without occupying stations apart. The minute diagnosis of these two species cannot be briefly given. It must suffice here to state that the most certain difference, as it is the most easily recognizable, is to be found in the tarsus, which in the arctic tern is a quarter of an inch shorter than in its kinsman. The remaining native species is the lesser tern, S. minuta, one of the smallest of the genus and readily to be distinguished by its permanently white forehead. All the species already mentioned, except the black tern, have much the same general coloration—the adults in summer plumage wearing a black cap and having the upper parts of the body and wings of a more or less pale grey, while they are mostly lighter beneath. They generally breed in association, often in the closest proximity—their nests, containing three eggs at most, being made on the shingle or among herbage. The young are hatched clothed in variegated down, and remain in the nest for some time. At this season the parents are almost regardless of human presence and expose themselves freely.

At least half-a-dozen other species have been recorded as occurring in British waters, and among them the Caspian tern, S. caspia, which is one of the largest of the genus and of wide distribution, though not breeding nearer to the shores of England than on Sylt and its neighbouring islands, which still afford lodgings for a few pairs. Another, the gull-billed tern, S. anglica, has also been not infrequently shot in England. All these species are now recognized—though the contrary was once maintained—as inhabitants of North America, and many go much farther. S. forsteri is the North American, and S. melanogaster the Indian tern.

Terns are found all over the world, and among exotic forms may be particularly mentioned the various species of noddy (q.v.). Often confounded with these last are the two species called in books sooty terns (S. fuliginosa and S. anaestheta), but by sailors “egg-birds” or “wide-awakes” from their cry. These crowd at certain seasons in innumerable multitude to certain islands within the tropics, where they breed, and the wonderful assemblage known as “wide-awake fair” on the island of Ascension has been more or less fully described from very ancient times. W. Dampier in his voyage to New Holland in 1699 particularly described and figured the sooty tern (Voyages, iii. p. 142), discriminating it from the noddy, from which it had not before been distinguished.  (A.N.) 

  1. “Starn” was used in Norfolk in the 19th century as a name for the bird commonly known as the black tern, thus confirming Turner, who, in 1544, describes what seems to have been the same species as “nostrati lingua sterna appellata.” In at least one instance the word has been confounded with one of the old forms of the modern Starling (q.v.). To Turner's name, repeated by Gesner and other authors, we owe the introduction by Linnaeus of Sterna into scientific nomenclature. “Ikstern” is another Dutch form of the word.
  2. It was known there as carr-swallow, carr-crow (corrupted into “scarecrow”), and blue dar (qu. = daw?).
  3. Linnaeus's diagnosis of his Sterna hirundo points to his having had an “arctic” tern before him; but it is certain that he did not suspect that specific appellation (already used by other writers for the “common” tern) to cover a second species. Some modern authorities disregard his name as being insufficiently definite, and much is to be said for this view of the case. Undoubtedly “hirundo” has now been used so indiscriminately for one species or the other as to cause confusion, which is perhaps best avoided by adopting the epithets of Naumann (Isis, 1819, p. 1847, 1848), who, acting on and confirming the discovery of Nitzsch (who first detected the specific differences), called the southern species S. fluviatilis and the northern S. macrura. Temminck's name S. arctica, applied to the latter a year afterwards, has, however, been most generally used for it.