LESSER TERN.
This species (Sterna minuta) is by far the smallest of the Terns that visit the British coasts in summer to breed. It cannot be said to be anywhere common, and its breeding stations are few and far between. Curiously enough, it is not known to breed on that great resort of British sea fowl, the Farne Islands. There can be no doubt that this Tern is slowly becoming rarer, and in view of this fact I do not feel justified in assisting its extermination, by naming a single locality known to me where it now breeds. The bird-loving reader will, I am sure, appreciate this reticence. Small colonies of this pretty Tern are situated here and there round the British coasts, and in one or two more inland localities. The partiality of the Lesser Tern for the coast of the mainland, rather than for islands, as a nesting ground, contributes largely to the decrease in its numbers. It arrives on our coasts in May, and is readily distinguished from all its congeners by its small size. In its habits it is certainly gregarious, but nowhere are its gatherings as extensive as in the other common British species. Like its congeners it is eminently a bird of the air, flying up and down in restless uncertain flight, living almost entirely on the wing during the daytime, only seeking the sands or the sea to sleep or to rest. It may be watched flying along the coast, a short distance from land, in a slow irregular way, every now and then poising for a second, and then dropping into the water with a tiny splash to seize a fish or a crustacean. Its note is not quite so harsh as that of the larger species, and may be described as a shrill pirr, most frequently uttered when its breeding places are invaded. Its food is composed of small fish, insects, sand-lice, and crustaceans, most of which is secured whilst the bird is on the wing.
The Lesser Tern begins breeding in June. Like all the other species it returns unfailingly to certain spots along the coast each summer, and may, therefore, be presumed to pair for life. Its favourite breeding-grounds are extensive stretches of sand, varied with slips and banks of coarser shingle. It makes no nest, not even so much as scratching a hollow for its eggs, but lays them on the bare ground. It is most interesting to remark that this Tern never lays its eggs on the fine sand, but always on the bits of rough beach—where the ground is strewn with little stones, broken shells, and other débris of the shore—where their colour harmonises so closely with surrounding objects that discovery is difficult. The eggs are from two to four in number—I have on two separate occasions taken clutches of the latter—but three may be given as the average. They vary from buff to grayish-brown in colour, blotched and spotted with various shades of darker brown and gray. During the hottest hours of the day the female sits but little upon them, and it is remarkable how quickly these shore birds will rise from their nests at the first sign of impending danger—the alarm doubtless being given by the male bird from the air above. It is a most exceptional thing to see a conspicuously coloured bird rise from its nest in a bare situation; the eggs are generally coloured protectively, and resemble the objects around them; the presence of the showily attired parent would inevitably lead to their discovery. Early in autumn, when the young are strong upon the wing, the return journey to the winter home on the African coast begins, and it is during these migration journeys that the bird is, perhaps, most commonly observed along the British seaboard.