The Tawny Owl, Strix aluco, known colloquially as the Brown Owl, is a robust bird of prey, with a body length ranging from 37 to 46 cm and a wingspan of 81 to 105 cm. It is a stocky, medium-sized owl, characterized by a large rounded head without ear tufts, and a facial disc that is usually plain, encircling dark brown eyes. The species exhibits sexual dimorphism, with females being larger than males.
The Tawny Owl has two color morphs, rufous brown and greyish brown, with both having whitish underparts streaked with brown. It flies with long glides on rounded wings, and its silent flight is facilitated by soft, furry upper surfaces on its feathers and a fringe on the leading edge of the outer primaries. The absence of ear tufts and its squat shape help distinguish it from other owls within its range.
This species thrives in deciduous and mixed forests, mature conifer plantations, and urban areas with green spaces such as cemeteries, gardens, and parks. It prefers habitats with access to water and is mainly found at lower elevations, although it can breed up to 2,800 meters in some regions.
The Tawny Owl is widespread across temperate Europe to western Siberia. It is non-migratory and highly territorial, with a distribution that stretches from Great Britain and the Iberian Peninsula to western Siberia.
The Tawny Owl is nocturnal and known for its territorial nature. It defends its territory with vigor and is fearless in the protection of its nest and young. Juveniles disperse to find their own territories after leaving the parental nest, and if unsuccessful, they often face starvation.
The male's hooting song is a quavering "hoo…ho, ho, hoo-hoo-hoo-hoo," while the female's contact call is a shrill "kew-wick." The stereotypical double hoot is a duet between male and female. The owl's vocal activity varies with sex, annual cycle stage, and weather conditions.
Tawny Owls are usually monogamous and breed in tree holes, old nests, or nest boxes. They lay a typical clutch of two or three eggs, which are incubated for about 30 days. The downy chicks fledge in 35-39 days, and the parents care for them for two to three months post-fledging.
The Tawny Owl can be confused with the Great Grey Owl, Eurasian Eagle-Owl, and Ural Owl due to their similar shape, but these species are significantly larger.
The Tawny Owl hunts primarily at night, preying on a variety of animals including rodents, other small mammals, birds, earthworms, and beetles. In urban areas, its diet includes a higher proportion of birds. It swallows prey whole and regurgitates indigestible parts as pellets.
The Tawny Owl is classified as Least Concern by the IUCN, with a stable or increasing population in most of its European range. It is listed in Appendix II of CITES, indicating that international trade is regulated to ensure its sustainability.