Eurasian Eagle Owl

Eurasian Eagle Owls

Bubo-bubo

Description: The upper-parts are brown-black and tawny-buff, showing as dense freckling on the forehead and crown, stripes on the nape, sides and back of the neck, and dark splotches on the pale ground colour of the back, mantle and scapulars. A narrow buff band, freckled with brown buff, runs up from the base of the bill, above the inner part of the eye and along the inner edge of the black-brown, “ear-tufts”.
The rump and upper tail-coverts are delicately patterned with dark vermiculations and fine wavy barring. The facial disc is tawny-buff, speckled with black-brown, so densely on the outer edge of the disc as to form a “frame” around the face. Chin and throat are white continuing down the centre of the upper breast
The whole of the underparts except for chin, throat and centre of upper breast is covered with fine dark wavy barring, on a tawny-buff ground colour. Legs and feet are likewise marked on a buff ground colour but more faintly.
The tail is tawny-buff, mottled dark grey-brown with about six black-brown bars.
Bill and claws are black, the iris is orange (yellow in some subspecies).

Size: Length: 58-71cm (22.8-28″)
Weight: Female 2280-4200g (80.4-158oz) Male 1620-3000g (57.1-105.8oz)
Average Wing Length (one wing only): Female 47.8cm (18.8″) Male 44.8cm (17.6″)

Voice: A deep, monotonous “oohu-oohu-oohu”. The female’s call is slightly higher than the male’s. When threatened, they may bark and growl.

Hunting & Food: Eagle Owls have various hunting techniques, and will take prey on the ground or in full flight. They may hunt in forests, but prefer open spaces.
Eagle Owls will eat almost anything the moves – from beetles to roe deer fawns. The major part of their diet consists of mammals (Voles, rats, mice, foxes, hares etc…), but birds of all kinds are also taken, including crows, ducks, grouse, seabirds, and even other birds of prey (including other owls). Other prey taken include snakes, lizards, frogs, fish, and crabs.
The most common type of prey depends largely on relative availability, but are usually voles and rats. In some coastal areas, they have been known to feed mainly on ducks and seabirds.
Pellets are somewhat compressed, irregularly cylindrical or conical shaped, averaging about 75 x 32 mm (3 x 1.25″).

Breeding: The Male and Female duet during courtship, the Male advertising potential breeding sites by scratching a shallow depression at the site and emitting staccato notes and clucking sounds. Favoured nest sites are sheltered cliff ledges, crevices between rocks and cave entrances in cliffs. They will also use abandoned nests of other large birds. If no such sites are available, they may nest on the ground between rocks, under fallen trunks, under a bush, or even at the base of a tree trunk. No nesting material is added. Often several potential depressions are offered to the female, who selects one; this is quite often used again in subsequent years. Very often pairs for life. They are territorial, but territories of neighbouring pairs may partly overlap.

Laying generally begins in late winter, sometimes later. One clutch per year of 1-4 white eggs are laid, measuring 56-73mm x 44.2- 53mm (2.2- 2.9″ x 1.7- 2.1″) and weighing 75- 80g (2.6- 2.8oz). They are normally laid at 3 days intervals and are incubated by the female alone, starting from the first egg, for 31-36 days. During this time, she is fed at the nest by her mate.
Once hatched, the young are brooded for about 2 weeks; the female stays with them at the nest for 4-5 weeks. For the first 2-3 weeks the male brings food to the nest or deposits it nearby, and the female feeds small pieces the young. At 3 weeks the chicks start to feed themselves and begin to swallow smaller items whole. At 5 weeks the young walk around the nesting area, and at 52 days are able to fly a few metres. They may leave ground nests as early as 22-25 days old, while elevated nests are left at an age of 5-7 weeks.

Fledged young are cared for by both parents for about 20-24 weeks. They become independent between September and November in Europe, and leave the parents’ territory (or are driven out by them). At this time the male begins to sing again and inspect potential future nesting sites.
Young reach maturity in the following year, but normally breed when 2-3I years old.

Mortality: Eurasian Eagle Owls may live more than 60 years in captivity. In the wild, about 20 years may be the maximum. They have no real natural enemies; electrocution, collision with traffic, and shooting are the main causes of death.

Habitat: Eagle Owls occupy a variety of habitats, from coniferous forests to warm deserts. Rocky landscapes are often favoured. Adequate food supply and nesting sites seem to be the most important prerequisites.