Vertebrate Zoology: A Tutorial - T. A. Dauda 2014

Metazoans
Class Aves
Superorder Carinatae – Order Strigiformes

The order comprises birds that are predominantly medium-sized, less often large or small, featuring a large HEAD and large, forward-facing eyes. Their beak is short, with the upper Mandible hooked at the tip. The legs are generally strong and feathered down to the claws, which are sharp and strongly curved.

The wings are broad and rounded, and the tail is short. The plumage is dense and soft yet loose, allowing for silent flight. On the front of the head, the feathers form a characteristic facial disc.

When at rest, the birds sit upright in a columnar posture.

Owls lead a nocturnal or crepuscular lifestyle. Orientation in flight and the detection of prey rely primarily on exceptionally well-developed Hearing. Fleshy Skin folds are located in front of the External ear openings to enhance the Condensation of sound waves.

At the same time, these birds possess excellent Vision, even at night. Scanning the surroundings is aided by an extremely flexible head capable of rotating through 270°.

Owls live singly or in pairs. They are monogamous. Nests are built on the ground, in tree hollows, or in other secluded spots. The clutch consists of 4–9 eggs. Incubation is performed mainly by the female, but both parents feed the nestlings. Development is altricial. They feed on various animals, most commonly small rodents.

Eighteen species inhabit Russia. Among them, widely distributed species include the short-eared owl, long-eared owl, northern hawk-owl, and the largest of all owls, the Eurasian eagle-owl; tawny owls such as the Ural, great grey, and tawny owl; and smaller pygmy owls, including the Eurasian pygmy owl and Boreal owl. These birds are absent from the northern extremes of Europe and Siberia, as well as certain southern regions of Asia.

Owls destroy harmful rodents. This benefit is further amplified by the fact that they hunt at night, when other birds of prey are asleep.