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.which appellations refer to the beetle-like hum uttered by the bird. The sound does not arise, as some suppose,
from the resistance of the air against the wide open mouth of the bird as it flies, for this singular sound is most frequently heard when the night-jar is sitting quietly on a branch. No doubt it is produced by some peculiar organisation of the mouth, and may be called the bird's song. The usual sound during flight is a sharp squeak, the deep musical hum being reserved for its solace, when, shrouded in a mass of foliage, the night-jar sees the quiet eve approaching.
But to what family of birds does the night-jar or fern-owl belong? It is, strictly speaking, a swallow, differing from the rest of the Hirundinida by coming abroad at night instead of the day, and is the only nocturnal bird of this large family. It might, therefore, be properly called the night-swallow.
Like the swallows, it is an insect-feeder, like them visits us only during summer, comes from the same region, Africa, and like them returns thither on the approach of winter. The middle of May witnesses the arrival of this interesting bird, and before the end of August it has left the woods and moors of England for the valleys of Egypt and the rocky wilds of Abyssinia. It is the only nocturnal bird amongst all our summer feathered visitors, which usually love the brightness and cheerfulness of daylight. Thus, whilst the day-swallows check the too rapid increase of those insects which appear by day, this night-swallow diminishes the numbers of those which fly abroad after sunset. Therefore the night-jar holds the same relation to the swallow tribes that the owls do to the Falconide. For, as the owl begins to prey when the hawk and eagle retire to their homes, so this bird continues the work of the martin, swift, and swallow during the times when such feathered hunters are inactive. Hence no class of insects is without a check, and men may be thankful that it is so ordered, as there are myriads of insects which only fly during the faint glimmer of twilight. These would be left to increase until every heath and copse swarmed with hosts of stinging and fierce little tormenters. The night-jar prevents this; and is the only bird, save the bat, which contributes to this end. The chafers and beetles, with
many insects injurious to man's works, form the food of the night-jar, which is thus not only a harmless but an actively useful visitant.
This bird measures about ten inches in length, and is therefore easily seen in the twilight as it flits to and fro round some old tree.
The flight is generally low, as the insects it pursues are mostly found near the ground ; the motion is soft, and generally resembles that of the owls; its sight is most acute, enabling the bird to detect the smallest insect in the faintest light; whilst their rapid and sudden evolutions render the capture of the most swift-winged flies and moths easy. The most remarkable peculiarities of this bird are its mouth and feet. The upper part of the beak is furnished with nine or ten bristles along its edge, which increases its power of capturing insects, as these bristles hang like a net over the open mouth, preventing the escape of the prey. This power is further increased by a glutinous substance attached to the bristles, which trammels the captured insects in their attempts to escape. The mouth is thus a kind of trap, capable of both seizing and holding its prey. The owl, though a nocturnal bird, is not provided with such a capturing apparatus, for the owl does not, like the night-jar, prey on insects, but on larger animals, which such a net-work of bristles would be of little use in taking; a nocturnal insect-hunter can, however, make most effective use of such a mouth-net. The day-swallows do not need this addition to their powers, as the light of day enables them to strike insects with the greatest certainty.
Another peculiarity of the night-jar is the saw or comb on the middle claw of each foot, and the use of which is to this day a mystery amongst naturalists. Wilson thinks it is given as a means of cleaning the bird's feathers from vermin. Other ornithologists take the same view, and contend that the leg and claw are specially adapted for cleansing the plumage ; but some suppose this toothed claw designed to assist the bird in seizing its prey. Gilbert White says, “ I saw the night-jar distinctly more than once put out its short leg while on the wing, and, by a bend of the head, deliver somewhat into its mouth. If it takes any part of its prey with its foot, as I have now the greatest reason to suppose it does these chafers, I no longer wonder at the use of its middle toe, which is curiously furnished with a serrated claw:"
Amidst such conflicting testimonies most will be ready to praise the philosophical besitation of Audobon, who says, “I wish I could have discovered the peculiar use of the pectinated claw which this bird has on each foot; but, reader, this remains one of the many desiderata in ornithology, and I fear, with me at least, it will continue so."
The young of the night-jar are often mistaken for the cuckoo, and a similarity has been demonstrated in the structure of the two birds by anatomists. In both, the crop, instead of being in front of the breast-bone, lies behind, which produces a peculiar fulness in the lower part of the bird's body. This circumstance has been used to disprove some assertions respecting the cuckoo, which has been supposed incapable of sitting on its eggs in consequence of the fulness of the crop over the intestines. But as the night-jar is formed in the same manner, and is proved to hatch its own eggs, the above argument respecting the incubation of the cuckoo fails in conclusiveness.
Some writers have made the night-jar resemble the cuckoo in the habit of not hatching its own eggs; and we find this asserted by a gentleman of considerable standing as a naturalist, who actually gives a case of a night-jar reared in the nest of a hedge
sparrow. All the details are minutely given; the visits of a large bird to the sparrow's nest, the size, colour, and appearance of the strange egg, the habits of the intruding young bird, and its growth, are noted; whilst, in the end, we are told that it was placed in a cage as a cuckoo, but turned out a night-jar.
Certainly, if this were the case, the circumstances would demand the consideration of naturalists; but there cannot be much doubt that the above account refers to a young cuckoo, which has been repeatedly mistaken for the night-jar by experienced ornithologists. We must remember that the cuckoo does not attain its proper colours till the third year; having previously many of the markings peculiar to the night-jar.
Hence it is not surprising to find this bird mistaken for the cuckoo ; but we cannot admit that the fern-owl deposits eggs in the nests of other birds. It does not certainly take much pains with its nest, being content with a hole in the ground amongst fern-roots, or at the foot of some dwarf shrub. The eggs are often found in July in such places, though a person must look closely to detect them, in consequence of their markings giving them the appearance of the oblong rounded stones found on
The night-jar is rarely seen perching in the daytime, as the deep foliage in which it rests conceals the bird from observation. When seen, it is generally sitting on the bough with its body in a line with the branch, the head towards the trunk, and tail pointing to the extremity of the branch, of which it almost appears a part.
All the habits of the night-jar are useful to the agriculturists, the food consisting wholly of insects; but it has been charged by some with inflicting a disease called “puckridge” on cattle. The night-jar is supposed to produce this malady by piercing the skin of beasts with its beak; but the real author of the evil is an insect which lays its eggs in the skin of animals, where the worms breed, and eat into the flesh. With this offence the nightjar is no more chargeable than the Lord Chancellor of England with the tricks of Joseph Ady.
It was formerly supposed that only one species of this bird existed in Europe, but a distinct species is said to have been discovered in Spain, in 1817, which the people call the lamala, but Kemminck has named it the Caprimulgus ruficollis, or red-necked goatsucker. If this be really a distinct species, it is very rare, as specimens are not found in any of the European museums, except that of Vienna. If Europe present but one or two species of the night-jar, the other parts of the globe exhibit nineteen or twenty, of which fifteen are American, two limited to India, one to Africa, and one to Australia. Of the American species, only three are found in the United States, two of which are known by the odd names of whip-poor-will and chuck-will's-widow. These syllables are said to resemble the notes uttered by the birds; and, if so, the appellations are as appropriate as singular. A brief description of the three species existing in the United States will close this chapter.
THE WHIP-POOR-WILL (Caprimulgus vociferus).
Wilson and Andubon describe this bird as assembling in flocks of hundreds, making the woods resound with their booming song, which, when uttered by hundreds at once, sounds gloomily in the stillness of night, and requires long usage ere the woodman can compose himself to sleep with such melancholy notes ringing around his solitary hut. The bird is regarded with much dread by the superstitious Indians, probably on account of its voice, which may seem to the wandering red man like the cries of his forefathers’ ghosts lamenting over the lost glory of their ancient hunting-grounds.
The same peculiarity of the mouth and claw which distinguishes the European night-jar, belongs to this American species, in which the bristles of the upper mandible are half an inch in length,
CHUCK-WILL'S-WIDOW (Caprimulgus Carolinensis).
The name is derived, as we have said, from the resemblance between the bird's notes and the above syllables, but the Latin appellation refers to its locality; the bird being chiefly found in Carosina, and is, therefore, properly designated the Carolina night-jar. Each syllable of the singular name is distinctly heard proceeding from the bird ; the sound resembling the distinct slow utterance of the words “chuck will,” with the paro “widow” more emphatically pronounced. These notes may often be heard at the distance of a mile when the evening is still, and the forest silence undisturbed by any of the thousand cries and screams of nocturnal animals, which come with such startling effect from the deeps of solemn woods.
The third species is the
AMERICAN NIGHT-HAWK (Caprimulgus Americanus), which differs from the proper night-jars in wanting the network of bristles along the bill, but resembles them in its habits of feeding and mode of flight. A more prolonged notice of the Caprimulgidæ is not required ; and we can but recommend our country
readers to watch for these birds during those beautiful walks which they are able to enjoy in the calm evenings of summer. Such as reside near heaths, woodlands, or parks, cannot fail to find the night-jar in their neighbourhood ; and frequently, when the swallow has retired to his nest, and the owl sails silently over the fields, will this night swallow be seen sweeping with powerful flight round bushes or trees where insect colonies dwell.
No bird will better repay our attention than this singular member of the feathered kingdom ; and its nocturnal habits bring it distinctly before us when other birds have retired from sight.
Those who have never seen this bird may receive some satisfactory ideas of its appearance from the figure prefixed to this account. The fern-owl is there represented on the wing, hunting for insects, and the wide mouth, armed with the bristles, is distinctly visible. The reader will observe that the beak opens back as far as the point under the eye, which must give this swallow ample means of seizing the most active insect with certainty.