TERNS AND THEIR NESTS.
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THE LESSER TERN.
The LESSER TERN (Sternula minuta) has been considered by some ornithologists as the representative of a distinct sub-family, although it only differs from the preceding species in its inferior size, proportionately strong short beak, the deeply-incised web of its foot, and the shallow furcation of its tail. In this bird the forehead and under side are white, the upper head and nape black, the mantle and wings dark green. The eye is brown, the beak yellow, with black point, and the foot clay-yellow. The length of this bird is eight inches and a half; breadth nineteen to twenty inches; length of wing seven, and tail three inches. The young are spotted like the preceding species. The range of the Lesser Tern extends over Europe, Asia, Africa, and America, from 24° to 58° north latitude. In Brazil it is replaced by a somewhat larger species. The Lesser Tern makes its appearance in Great Britain about May, and after having reared its young, resumes its wandering habits about the end of July or August. It is, however, a slow traveller, and only reaches the lakes and streams of North Africa in the autumn; its migrations from North Asia and North America are conducted in a similar manner. This species prefers fresh to salt water, and chiefly frequents large rivers without, however, altogether withdrawing from the sea-shore. The first requisite for its accommodation would seem to be a little island or bed in a stream, covered with gravel or sand, for where these are wanting it is never to be found. Although the two or three eggs of the Lesser Tern (which have a stone-coloured shell marked with grey, or reddish brown) are usually merely deposited in a slight depression of the ground above high-water mark, Audubon states that some pairs that he found breeding on the coasts of Labrador had formed very snug nests composed of short fragments of moss, well matted together, while those on the island near the Bay of Gaveston had laid their eggs on dry drifted weeds, which appeared to have been gathered by them for this purpose. The same author tells us that the common note of this bird resembles that of the Barn Swallow when disturbed about its nest, and is at times as smartly and rapidly repeated. The following very pretty description of the light and beautiful movements of this Tern whilst on the wing is from the pen of Mr. Macgillivray:—"In the elegance of its buoyant flight as it skims over the waters or shoots on its way to and from its breeding-place, the tiny creature must be an object of admiration to every lover of nature. You may see a pair coming up from a distance flying at the height of a few yards over the waves, their long wings winnowing the air and impelling them in starts, as it were, as they wend their way in undulating and wavering movements. Suddenly their flight is arrested over a large pool left on the sands by the retiring tide; with quick beats of their wings, they hover stationary, or but slightly shifting place, and with downward-pointed bill seem intent on something which they perceive in the water. One drops, but not like a stone, dips, but with upraised wings, and rises with a small fish in its bill. The other is similarly successful. Onward they proceed, now and then emitting a shrill cry and with gentle beats of their wings. Far ahead is a flock engaged in picking up their prey, and onward they speed to join their kindred." Although these birds usually swallow their prey whilst in the air they are occasionally seen to alight upon the ground with their booty, and there devour it piecemeal.
The WATER SWALLOWS (Hydrochelidon) constitute a well-defined group belonging to the Tern family. These birds are powerfully built and of elegant appearance; their beak is feeble, tarsus high, toes long and united by a deeply-incised web. The wing is very long, tail short and but little forked. The general plumage, which is soft and thick, is during the breeding season principally black; this latter character, however, varies much according to the age of the bird and season of the year.
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THE BLACK MARSH TERN.
The BLACK MARSH TERN (Hydrochelidon nigra) is of a deep rich black on the head, nape, breast, and centre of belly; the mantle is blueish grey, and the region of vent white. The wing-quills are dark grey bordered with a lighter shade, and the tail-feathers dark grey. The eye is brown, beak greyish black with red base, and foot brownish red. In the winter dress, only the back of the head and nape are black, the forehead and under part being white. In young birds the mantle-feathers and wing-covers are edged with reddish yellow. The length of this species is nine inches, span of wings twenty-six inches. The Black Tern inhabits the north temperate zone, and during the winter wanders so far south, that, like Sternula minuta, it is to be met with in four continents—Europe, Asia, Africa, and America. It makes its appearance in Great Britain at the same time as the other Terns, but is much less abundant than formerly, being seldom seen in the North of England and very rarely in Scotland, although it still visits many parts of Ireland. It arrives in this country about the end of April or beginning of May, and is principally found in Lincolnshire, Norfolk, and Cambridgeshire. In Montagu's time it was common in Romney Marsh, in Kent; specimens have also been procured in other southern counties. During their winter peregrinations these birds generally travel in companies varying from twenty to about a thousand individuals, following the course of the streams, and taking up a temporary residence wherever these spread out into extensive swamps or overflow the neighbouring land. In their deportment, food, and mode of breeding, they also differ materially from the Common Terns. They walk seldom, and as badly as their brethren, and rarely swim, as their powers in that respect are very limited. Their flight is not so rapid and devious as that of their congeners, but more even, gentle, and light. During the night season they betake themselves to repose, but in the daytime are constantly on the wing, hunting after food. The Black Terns live almost exclusively upon insects, although they will also occasionally seize a little fish or other small inhabitant of the water. They somewhat resemble the Swallows in their mode of life, and like them may be seen skimming over pools of water, apparently more for the sake of amusement than from any real necessity for such active exertion. When they discover anything in the shape of food, they hover over it for an instant and pounce upon their prey, not coming down upon it precipitately and perpendicularly as some of the Divers do, but sweeping obliquely towards it, so as to seize it with the beak without immersing their bodies. According to Montagu, "The flight of this species is not unlike that of the Goatsucker; its evolutions are rapid and it turns short if attacked, by which means it escapes the talons of predaceous birds, as we once had an opportunity of witnessing. In a very hard gale of wind many Terns were sporting over the water, when a Peregrine Falcon passed like a shot, singled out his bird and presently coming up with the chase, made a pounce, but the great dexterity of the Tern avoided the deadly stroke and took a new direction. The Falcon, by his superior velocity, soon regained sufficient elevation to successively repeat his pounces, but at last relinquished the pursuit." The Black Terns, unlike the generality of their congeners, are fearless and unsuspicious, and seem rather to welcome than to avoid the presence of mankind; if molested, however, they soon become more wary. Towards each other they manifest considerable affection, and should one of their party be shot, the others instantly collect around their wounded companion, not from any sinister motives, as has been asserted by some writers, but out of commiseration for his condition. For their breeding-places these birds invariably choose some wide swamp or morass, placing their nests upon little heaps of mud that project above the surface of the water, upon tufts of grass or sedge, upon floating masses of reeds, rushes, or similar materials, or sometimes on the floating leaves of aquatic plants. The nest itself is constructed of substances that vary with the locality selected, such as leaves, roots and rushes heaped carelessly together. In this cradle, about the beginning[Pg 183] of June, each pair lays two, three, or four eggs; these are of a pale olive or yellowish colour, spotted with grey, reddish brown, and brownish black. Both sexes incubate by turns, keeping the eggs constantly covered. If disturbed during the breeding season, these Terns are as noisy as any of their congeners, but unlike them remain close over the nest and only go in search of food at regular intervals. After the lapse of fourteen or sixteen days the young make their appearance, and about a fortnight later quit the nest. Even after they are fully fledged they accompany their parents, who tend them with great devotion, and feed them while on the wing, after the manner of Swallows. This species subsists chiefly on shell-fish, beetles, and dragon-flies. The flesh of the Black Terns is tolerably good.
THE WHITE-WINGED TERN.