| Owls (Latin: Strigiformes, or Striges) are a sroup of birds of prey, including more than 220 extant species, nocturnal birds and found in all regions of the Earth.
Some owls are active during the day, as an example, from Russian owls — white owl (Bubo scandiacus), pygmy owl (Glaucidium passerinum) & hawk owl (Surnia ulula) and several others such as little owl (Athene noctua) are crepuscular (active during the twilight hours of dawn and dusk). However, majority of owls are genuinely nocturnal and many of them freely fly even in complete darkness, which can be judged by the screeches of owls. Flight of the owl is practically silent and allows them to unnoticeably fly upto the resting preys. While hunting, owls, which fly silently, make screeches from time to time to flush the prey with its unexpectedness. Apparently, owls do this to identify the prey.Usual food of owls consists of tiny rodents and smaller owls predominantly feed on large insects and some owls relish fishes. Very rarely owls attack birds and hence should, in comparison with ancient birds of prey (particularly falcons), be considered as useful birds.
Majority of owls live in forests or in woodlands and only few, as for example, short-eared owl (Asio flammeus), prefer open places. Some owls, for example, little owl or barn owls (Tyto alba) - willingly settle under roofs and on attics of houses. Hollows in old trees serve as nests whereas owls lay eggs usually without any litter. In comparison, eggs of owls are very small and usually white and almost spherical in shape.
According to their anatomic features and with respect to plumage, the owls drastically differ from diurnal predators and hence are grouped into independent family by some ornithologists. The following are the peculiarities of the owl’s skeleton: existence of outgrowths of basilar bone, original triple articulation of lower jaw with skull, very short phalanxes of third finger, mobility of exterior finger, which can bend backwards, and at last, existence of hollows on rear edge of breastbone in most of the types (barn-owls are an exception).
Eyes of owls are very large and forward facing, in proportion to position of eye sockets on front side of the facial side of skull. Pupil to a great extent narrows and extends not only during changes in illumination but also during each inhalation and exhalation. Like vision, hearing of owls is also extremely keen. In comparison, exterior ear is large and can be covered from outside by plumage mobile folds of the skin; radiant flags, around the ear apertures, form like outer earflap.
Majority portion of owls is painted dimly; usually grey or rust shades with more or less densely scattered black spots, strips and burnets; Dull coloration of an owl’s feathers blends well with the ambient background and almost makes the owls invisible during twilight.
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