Tawny Owl

The tawny owl, commonly known as the brown owl or the tawnies, is one of the most common owl species. This owl has 11 known subspecies, some of which are Strix aluco aluco, Strix aluco biddulphi, Strix aluco willkonskii, Strix aluco sanctinicolai, and Strix aluco harmsi.

The tawny owl is a bit larger than the barn owl. Also, the color of this owl varies from mottled reddish brown to grey, while the barn owls are a shade of buff, grey and white.

Description

Size: Length: 15–18 inches (37–46 cm)

Weight: 0.85 – 1.8 lbs. (385-816 gm)

Wingspan: 32–41 inches (81–105 cm)

Body and Coloration: These medium-sized birds have round heads with no ear tufts, dark eyes, and stocky bodies. The under part of their bodies has a pale tone covered with brown streaks. Females are usually larger than males.

Their coloration varies geographically; for example, owls in the western part of Europe are brown, while grey tawny owls are more common in the eastern and the northern region of Europe; also, the subspecies of the north are typically larger than the southern ones and have longer wings. Asian counterparts of these birds have fine facial disc lines and barred underparts.

Range and Distribution

The distribution of this owl ranges across Central and Western Asia, Europe, and North Africa. They are native to the British Isles except in northern Scotland and Ireland.

Habitat

Their preferred habitat is mixed forests and temperate deciduous forests. They also inhabit coniferous forests, riparian woodland, riverine forests, open landscapes with old trees, the tiga, as well as near human settlements.

Diet

These owls’ primary diet consists of fish, frogs, rabbits, reptiles, small birds, wood mice, and voles, as well as other species of owls; one example is the long-eared owl.

Behavior

• Primarily nocturnal, these birds are sometimes active during the day.
• Territories are established with screeching calls and threatening behavior like fights in mid-flight.
• They are highly territorial and defend their home range throughout the year; males and females maintain the territories.
• Their calls consist of hoots and sharp “kee-wick” sounds. The males usually make the hooting calls with the first note of a quavering ‘twoo’ followed by a second note with a pause between the two. The females make the “kee-wick” sounds.
• These birds are non-migratory.
• This owl typically nests in tree holes to protect the eggs and the young from predators.

Lifespan

The average lifespan of a tawny owl ranges between 4-6 years.

Adaptations

• Due to having front-facing eyes acquired from evolution, they have developed better binocular vision, which is 100 times better than that of humans. They can see up to 1650 feet from their location, which aids them in hunting at night.
• Like most other species of owls, they also have asymmetrical ears, which help them hear the slightest sound their prey might make.
• Their large wings let them float in the air without having to flap their wings repeatedly; this leads them to fly silently without notifying their presence to their prey or predators.

Mating and Reproduction

These birds are monogamous and therefore have the same partner for life. The breeding season lasts from January-July. After spotting a suitable mate during courtship, the male chase the female with consecutive hoots; then, they proceed with their courtship display on a nearby tree by raising their wings and Swaying while walking along the branch.

Females may lay a clutch of 1-9 white glossy eggs, but a clutch of 2-3 eggs is most common. Owlets hatch after 30 days of incubation. After 35-39 days, the owlets start fledging and take about two weeks more to fly properly. They reach their reproductive maturity at the age of one. However, they only mate after they become 2-3 years old.

Predators

Predators like pine martens and red foxes hunt these owls. Some birds of prey, such as common buzzards, northern goshawks, and other owl species, namely eagle owls and Ural owls, also prey on them. Sometimes Eurasian jackdaws make their nests above tawny owls’ nests and kill adults and owlets.

Conservation Status

In the Red List of Threatened Species by the IUCN, the tawny owl is listed as “Least Concern” or “LC”.

Interesting Facts

• The three oldest recorded tawny owls are; 14 years old from Sweden, 18 years and 7 months old from central Europe, and 21 years and 11 months old from Switzerland.
• Over the past half-century, the tawny owls have evolved from grey to brown to survive in warmer climates. This evolution took place due to climate change.