NOCTURNAL BIRDS OF PREY

“The brown owl, the horned owl, the barn-owl and other species of this family, are known under the name of nocturnal birds of prey. They are called birds of prey because they live on the small animals that they catch, such as rats and mice, both those that infest our houses and those that live in the fields. Owls are, among birds, what cats are among quadrupeds,—the inveterate foes of all those small rodents of which the mouse is our most familiar example.

“The French language has recognized this analogy in its term chat-huant1 (hooting cat) applied to a certain kind of owl. This bird is, in some sort, a cat in its manner of living, a cat that flies and that utters a long-drawn cry like a plaintive howl. It is nocturnal; in other words, it keeps itself hidden by day in some obscure retreat, whence it comes forth only at nightfall, to hunt in the twilight and under the rays of the moon.

“Owls have eyes of remarkable size, round, and both in a frontal position instead of being placed one on each side of the head. A broad rim of fine feathers encircles each eye. The reason for their [296]great size is found in the bird’s nocturnal habits. Having to seek its food by a very feeble light, it must, in order to see with any distinctness, have eyes that admit as much light as possible; that is, eyes that open very wide.

“But this wide-openness of the eyes, so advantageous by night, is a serious inconvenience to the owl in the bright light of day. Dazzled, blinded, by the sun’s rays, the bird of darkness keeps itself in hiding and dares not venture forth; but if forced to do so, it observes the utmost circumspection, flying with cautious hesitation and by short stages. The other birds, those accustomed to broad daylight, come and insult it at will. Robin redbreast and the tomtit are the first to pay their compliments in this manner, and are followed by the chaffinch, the jay, and many others.”

Barn-owl

“And doesn’t the owl do anything to get even with them?” asked Jules.

“Very little,” replied his uncle. “Perched on a branch of some tree, the night bird answers its aggressors by a grotesque balancing of its body, turning its large head this way and that in a ridiculous [297]fashion, and rolling its eyes in bewildered alarm. Its menaces are vain: the smallest and weakest birds are its boldest tormentors, pecking it and pulling its feathers without its daring to defend itself.

“Because of its wide-open eyes the nocturnal bird of prey needs a subdued light like that of early dawn and of evening dusk. It is, therefore, at nightfall and at the first signs of daybreak that these birds leave their retreats and seek their prey. At these hours their hunt is a fruitful one, for they find the rats and mice, whether those that lurk about our houses and barns or those that live in the field, either fast asleep or on the point of going to sleep. Moonlight nights are the most favorable for the nocturnal bird’s purposes. Such nights are nights of plenty, affording opportunity for protracted hunting and many captures.

“Let us follow the owl on its nocturnal expedition. The moment is propitious, the air is calm, the moon shines. The bird leaves its sylvan retreat; it skims over the open field, the meadow, the prairie; it inspects the furrows where the field-mouse lurks, the long grass where it burrows, the ruins of deserted buildings where both rats and mice scamper about.

“Its flight is noiseless, its silent wing cleaving the air without the faintest sound. It is careful not to give the alarm to its destined victims. This noiseless flight it owes to the structure of its feathers, which are silky and finely divided. Nothing betrays its sudden coming, and the prey is seized without even suspecting the enemy’s presence. An extraordinarily [298]keen sense of hearing, on the other hand, advises the bird of all that is going on in the neighborhood. Its ears, large and deep, perceive the mere rustle of a field-mouse in the grass.

“The prey is seized with two strong claws warmly clothed in feathers clear down to the very nails. Each foot has four toes, of which three ordinarily point forward, and one backward; but, by a privilege common to nocturnal birds of prey, one of the anterior toes is movable and can point backward, so that the claw becomes divided into two pairs of equally powerful grippers when the bird wishes to seize, as in a vise, the branch whereon it perches or the victim struggling to escape.

“A blow of the beak breaks the head of the captured rat. This beak is short and hooked, and the two mandibles have great mobility, which enables them, in striking against each other, to make a rapid clacking, a demonstration by which the bird expresses anger or alarm.

“The mandibles open wide in the act of swallowing, revealing a mouth of ample proportions and a throat of excessive width. The prey, which has first been well kneaded by the claws, disappears down this throat, bones and all. Nothing is left of the rat or the mouse, not even the fur.

“Digestion completed, there remains in the stomach a confused mass of skins turned inside out and still wearing their fur, and bones stripped as clean as if they had been scraped with a knife. The bird then proceeds to rid itself of this encumbrance of [299]innutritious matter. Grotesque retchings indicate the labor of this deliverance. Something makes its way upward through the extended throat, the beak opens, and the act is accomplished. A rounded mass falls to the ground, composed of skins, bones, hair, scales—in fact, everything that has defied digestion. All nocturnal birds of prey have this ignoble manner of freeing the stomach: they vomit in globular form the residue of their prey after the latter has been swallowed whole.”