The Mottled Owl, (_Strix Asio_) or Screech Owl, is somewhat larger than the Acadian or Whetsaw, and not so familiar as the Barn Owl of Europe, though resembling it in general habits. He commonly builds in the hollow of an old tree, also in deserted buildings, whither he resorts in the daytime to find repose and to escape annoyance. His voice is heard most frequently in the latter part of summer, when the young Owlets are abroad, and use their cries for purposes of mutual salutation and recognition. This wailing note is singularly wild, and not unmusical. It is not properly a screech or a scream, like that of the Hawk or the Peacock, but rather a sort of moaning melody, half music and half bewailment. This wailing song is far from disagreeable, though it has a cadence which is expressive of dreariness and melancholy. It might be performed on a small flute, by commencing with D octave and running down by semitones to a fifth below, and frequently repeating the notes, for the space of a minute, with occasional pauses and slight variations, sometimes ascending as well as descending the scale. The bird does not slur the passages, but utters them with a sort of trembling _staccato_. The separate notes may be distinctly perceived, with intervals of about a semitone.
The Owl is not properly regarded as a useful bird. The generality of the tribe deserve to be considered only as mischievous birds of prey, and no more entitled to mercy and protection than the Falcons, to which they are allied. All the little Owls, however, though guilty of destroying small birds, are very serviceable in ridding our fields and premises of mischievous animals. They likewise destroy multitudes of large nocturnal insects, flying above the summits of the trees in pursuit of them, while at other times their flight is low, when watching for the small animals that run upon the ground. It is probably on account of its low flight that the Owl is seldom seen on the wing. Bats, which are employed by Nature for the same kind of services, fall victims in large numbers to the Owls of different species, who are the principal means of preventing their multiplication.
I should wander from my present purpose, were I to attempt a sketch of the large Owls, as I design only to treat of those birds which contribute, either as poetic or picturesque objects, to improve the charms of Nature. I shall say but a passing word, therefore, of the Great Snowy Owl, almost exclusively an inhabitant of the Arctic regions, where he frightens both man and beast with his dismal hootings,--or of the Cat Owl, the prince of these monsters, who should be consecrated to Pluto,--or of his brother monster, the Gray Owl, that will carry off a full-grown rabbit. There are several other species, more or less interesting, ridiculous, or frightful. I will leave them, to speak of birds of more pleasing habits and a more innocent character.