Their migrations are carried on over so great an extent, and that so loosely, that you might conceive it their desire to glean the whole country, as they advance with a front extending from the mouths of the Mississippi to the Rocky Mountains, passing in this manner from the south far beyond our eastern boundary lines. Thus they are enabled to disperse and breed throughout the whole Western and Eastern States, from South Carolina to Maine. On their way they may be seen passing over our cities and villages, alighting on the trees that embellish our streets, and even on chimney tops, from which they are heard to squeak their sharp notes, to the amusement or surprise of those who observe them.
I have seen this species in the British Provinces of New Brunswick and Nova Scotia, where they remain so late as the beginning of October, but I observed none in Newfoundland, or on the shores of Labrador. In going north, their appearance in the Middle States is about the first of May; but they seldom reach Maine before June.
The Night-Hawk has a firm, light, and greatly prolonged flight. In dull cloudy weather, it may be seen on the wing during the whole day, and is more clamorous than at any other time. The motions of its wings while flying are peculiarly graceful, and the playfulness which it evinces renders its flight quite interesting. The bird appears to glide through the air with all imaginable ease, assisting its ascent, or supporting itself on high, by irregular hurried flappings performed at intervals, as if it had unexpectedly fallen in with its prey, pursued, and seized it. Its onward motion is then continued. It moves in this manner, either upwards in circles, emitting a loud sharp squeak at the beginning of each sudden start it takes, or straight downwards, then to the right or left whether high or low, as it presses onward, now skimming closely over the rivers, lakes, or shores of the Atlantic, and again wending its way over the forests or mountain tops. During the love season its mode of flight is particularly interesting: the male may be said to court his mate entirely on the wing, strutting as it were through the air, and performing a variety of evolutions with the greatest ease and elegance, insomuch that no bird with which I am acquainted can rival it in this respect.
It frequently raises itself a hundred yards, sometimes much more, and apparently in the same careless manner already mentioned, its squeaking notes becoming louder and more frequent the higher it ascends; when, checking its course, it at once glides obliquely downwards, with wings and tail half closed, and with such rapidity that a person might easily conceive it to be about to dash itself against the ground. But when close to the earth, often at no greater distance than a few feet, it instantaneously stretches out its wings, so as to be nearly directed downwards at right angles with the body, expands its tail, and thus suddenly checks its downward career. It then brushes as it were, through the air, with inconceivable force, in a semicircular line of a few yards in extent. This is the moment when the singular noise produced by this bird is heard, for the next instant it rises in an almost perpendicular course, and soon begins anew this curious mode of courtship. The concussion caused, at the time the bird passes the centre of its plunge, by the new position of its wings, which are now brought almost instantly to the wind, like the sails of a ship suddenly thrown aback, is the cause of this singular noise. The female does not produce this, although she frequently squeaks whilst on the wing.
Sometimes, when several males are paying their addresses to the same female, the sight of those beaux plunging through the air in different directions, is curious and highly entertaining. This play is quickly over, however, for no sooner has the female made her choice, than her approved gives chase to all intruders, drives them beyond his dominions, and returns with exultation, plunging and gambolling on the wing, but with less force, and without nearing the ground.
In windy weather, and as the dusk of the evening increases, the Night-Hawk flies lower and more swiftly than ever, making wide and irregular deviations from its general course, to overtake an insect which its keen eye has seen at a distance, after which it continues onward as before. When darkness comes on, it alights either on the ground or on a tree, where it spends the night, now and then uttering its squeak.
These birds can scarcely walk on the ground, on account of the small size and position of their legs, which are placed very far back, for which reason they cannot stand erect, but rest their breast on the ground, or on the branch of a tree, on which they are obliged to alight sidewise. They alight with ease, however, and squat on branches or fence-rails, now and then on the tops of houses or barns. In all such positions they are easily approached. I have neared them when on a fence or low wall to within a few feet, when they would look upon me with their large mild eyes more as a friend than an enemy, although they flew off the moment they observed any thing suspicious in my movements. They now and then squeak while thus seated, and when this happens when they are perched on the trees of our cities, they seldom fail to attract the attention of persons passing.
In Louisiana this species is called by the French Creoles "Crapaud volant," in Virginia "Bat;" but the name by which it is most commonly known is "Night-Hawk." The beauty and rapidity of its motions render it a tempting object to sportsmen generally, and its flesh is by no means unpalatable. Thousands are shot on their return to the south during the autumn, when they are fat and juicy. Now and then at this season, they plunge through the air, but the rustling sound of their wings at this or any other time after the love season is less remarkable.
In the Middle States, about the 20th of May, the Night-Hawk, without much care as to situation, deposits its two, almost oval, freckled eggs, on the bare ground, or on an elevated spot in the ploughed fields, or even on the naked rock, sometimes in barren or open places in the skirts of the woods, never entering their depths. No nest is ever constructed, nor is the least preparation made by scooping the ground. They never, I believe, raise more than one brood in a season. The young are for some time covered with a soft down, the colour of which, being a dusky brown, greatly contributes to their safety. Should the female be disturbed during incubation, she makes her escape, pretending lameness, fluttering and trembling, until she feels assured that you have lost sight of her eggs or young, after which she flies off, and does not return until you have withdrawn, but she will suffer you to approach her, if unseen, until within a foot or two of her eggs. During incubation, the male and female sit alternately. After the young are tolerably grown, and require less warmth from their parents, the latter are generally found in their immediate neighbourhood, quietly squatted on some fence, rail, or tree, where they remain so very silent and motionless that it is no easy matter to discover them.
When wounded they scramble off very awkwardly, and if taken in the hand immediately open their mouth to its full extent repeatedly, as if the mandibles moved on hinges worked by a spring. They also strike with their wings in the manner of pigeons, but without any effect.