Birds - Black Tern
( Originally Published 1904 )
(Hydrochelidon nigra surinamensis)
Called also : SHORT-TAILED TERN
Length—9.50 to 10 inches.
Male and Female—In summer: Head, neck all around, and under parts jet black, except the under tail coverts, which are white. Back, wings, and tail slate color. In winter: Very different: forehead, sides of head, nape, and under parts white; under wing coverts only, ashy gray; back of the head mixed black and white; mantle over back, wings, and tail, deep pearl gray. Many feathers with white edges. In the process of molt, head and under parts show black and white patches. Immature' specimens resemble the winter birds, except that their upper parts are more or less mixed with brownish, and their sides washed with grayish.
Range—North America at large, in the interior and along the coasts, but most abundant inland; nests from Kansas and Illinois northward, but not on the Atlantic coast.
Season—Irregular migrant on the Atlantic coast from Prince Edward's Island southward. Common summer resident inland. May to August or September.
Although eastern people rarely see this dusky member of a tribe they are wont to think of as having particularly delicate pearl and white plumage, it is the most abundant species in the west, and indeed the only one of the entire order of long-winged swimmers that commonly nests far away from the sea in the United States. Early in May it arrives in large flocks that have gathered on the way from Brazil and Chile to nest in theMiddle States, west of the Alleghanies, and northward. A large colony takes up its residence in the fresh-water marshes and reedy sloughs so abundant in southern Illinois and elsewhere in the middle west; and although the birds have apparently mated during the migration, if not before, there are many flirtations and petty jealousies exhibited before family cares banish all non-sense in June. Not that the bird makes any effort to construct a nest, in which case it could hardly be a tern at all, so easy-going are all the family in this respect; nor that it is depressed by long, patient sittings on the eggs, for the incubating is, for the most part, left to the sun, when it shines; but all terns are devoted parents, however emancipated they are from much of the parental drudgery. Sometimes the eggs are laid directly on the wet, boggy ground; others in a saucer-shaped structure of decayed reeds and other vegetation, often wet and floating about in the slough ; and again they have been found in better constructed, more compact cradles, resting on the flat foundation of the home of the water rat. The eggs are two or three, grayish olive brown, sometimes very pale and clean, marked with spots and splashes of many sizes, but chiefly large and bold masses that have a tendency to encircle the larger end.
To visit a marsh when several hundred of these aquatic nests keep the cloud of dusky little parents in a state of panic, is to become deaf and dazed by the terrific din of harsh, screaming cries uttered by the little black birds that encircle one's head, menacing, darting, yet doing nothing worse than needlessly tormenting themselves. Retreat to a good point of vantage to watch the colony, and it quickly regains its lost confidence to the point of ignoring your presence; and the jolly company skim, soar, hover on outstretched wings, then dart in and out in a path-less maze that fascinates the sight. The flight is exquisite, swift, graceful, buoyant, and apparently without the slightest effort. Occasionally a bird will descend from the aerial game, and, checking its flight above its nest, poise for an instant on quivering wings, held high above its back, as if it spurned the earth.
Doubtless the diet of insects, which must be pursued and captured on the wing in many cases, cultivates much of the dash and impetuosity so characteristic of this tern. Fish appear to form no part of its bill of fare. It may " frequently be seen dashing about in a zig-zag manner," writes Thompson in his "Birds of Manitoba," and "so swiftly the eye can offer no explanation of its motive until . . . a large dragon-fly is seen hanging from its bill." Beetles, grasshoppers, and aquatic insects of many kinds encourage other extraordinary feats of flight. Mr. Thompson tells of meeting these birds far out on the dry, open plains, scouring the country for food at a distance of miles from its nesting ground. John Burroughs once had brought to him, to identify, a sooty tern, a near relative of the black species, that a farmer had picked up exhausted and emaciated in his meadow, fully one hundred and fifty miles from the sea, and at least two thousand miles from the Florida Keys, the bird's chosen habitat.
It had starved to death, he says, "ruined by too much wing. Another Icarus. Its great power of flight had made it bold and venturesome, and had carried it so far out of its range that it starved before it could return."
By the end of July the young black terns have sufficiently developed to join the flocks of adults that even thus early show the restlessness called forth by the instinct for migration. In August migration commences in earnest; and when we see the birds east of the Alleghanies, they are usually on their journey south, the only time they show a preference for the Atlantic coast.