The Tawny Owl (Strix aluco) is Sweden's most common owl and the species behind the familiar hooting heard from the forest on autumn nights. It is a compact, medium-sized owl measuring 37–43 cm in length with a wingspan of 81–105 cm and a weight of 400–800 grams. The head is large and round with no ear tufts, the eyes are dark, and the plumage comes in either a grey-brown or a reddish-brown colour morph, both pale below with dark streaking. This stocky, tuftless silhouette is one of the clearest ways to tell it apart from Sweden's other owls.
The species is best known for its call: the male's rich "hu … huuu-hu-hu-hu-huoo" answered by the female's sharp "kuwitt," a duet heard from autumn through to early spring and most vocal in November through March. Tawny Owls are strictly resident and fiercely territorial, occupying deciduous and mixed forest, parks and cemeteries across Sweden up to northern Svealand, with a population of 20,000–30,000 pairs; many first-year birds that fail to find a vacant territory starve. They nest in tree hollows or large purpose-built owl boxes, laying three or four eggs incubated for 28–30 days, with young remaining in the nest for a further 32–37 days; the female defends the nest aggressively and has been known to attack people who come too close during breeding. Hunting mainly at night from a perch, they take voles and mice as their principal prey, supplemented by small birds, frogs and larger insects, relying on their strong territorial fidelity and hunting skill to see them through even harsh winters without needing to migrate.
Read about this species in Swedish →