Eurasian Eagle-Owl (Bubo bubo): Facts, Size and Habitat

Appearance: how to recognize an eagle-owl

The eagle-owl is a bulky, barrel-chested bird with a big head and two prominent tufts of feathers on top that look like horns or ears. These tufts are only feathers, used in display and camouflage; the real ears are hidden openings on the sides of the head. Read more in what are owl ear tufts for?.

The plumage is tawny buff to warm brown, heavily streaked with black on the breast and finely barred on the belly. The upperparts are mottled dark brown and buff, which makes a roosting owl almost invisible against rock or bark. The facial disc, the flat ring of feathers around the face, is less sharply framed than in many owls. The throat has a white patch that males puff out when they call.

The most striking feature is the eyes. In most European birds the iris is deep orange, sometimes almost red, while birds from dry regions of Central Asia tend to have yellow-orange eyes. The legs and feet are feathered almost to the large black talons. Coloring varies across the range: birds from Siberia are pale and frosty gray, while those of southern Europe are darker and richer brown.

How big is a Eurasian eagle-owl?

This is one of the largest owls on Earth, smaller than a golden eagle but bigger than a snowy owl. As in most owls, females are larger and heavier than males.

Size also changes with geography. The biggest birds live in Russia and Siberia, while those of Spain and Portugal are among the smallest. The heaviest eagle-owls ever weighed, about 4.6 kg (10 lb), equal the top weight recorded for Blakiston’s fish owl, which is why the title of “biggest owl” is close and debated. See what is the biggest owl in the world? for the full comparison.

Habitat and range

The Eurasian eagle-owl is one of the most widespread owls in the Old World. Its range runs from Spain and Portugal across most of continental Europe and Scandinavia, through Russia and Central Asia to China, Korea, Sakhalin and the Russian Far East, with scattered populations in Turkey, the Middle East and the Himalayas. It is absent from the true Arctic tundra and from tropical rainforest.

What eagle-owls need most is rugged ground. They are most common where cliffs, ravines, rocky slopes or quarries lie next to woodland, scrub, farmland or wetland rich in prey. They also live in northern coniferous forest, steppe and the edges of semi-desert, and range from sea cliffs up to about 2,100 m (6,900 ft) in the Alps and over 4,000 m (13,000 ft) on the Tibetan Plateau. In recent decades a few pairs have moved into quiet parts of European cities such as Helsinki, where they hunt rabbits and rats.

Eagle-owls are not migratory. Adults usually hold the same territory for life, and only young birds roam widely while they search for a home of their own.

Diet and hunting

Eagle-owls are powerful, opportunistic hunters that take whatever medium-sized prey is common locally. Mammals usually make up most of the diet, especially voles, rats, rabbits and hares, along with hedgehogs, squirrels and young martens. Birds are also important, from pigeons, crows and ducks to gulls, herons and game birds. Frogs, reptiles, fish and large insects are eaten too.

The eagle-owl sits at the top of its food chain, and it regularly kills other birds of prey, including buzzards, kites, goshawks and smaller owls. Tawny owls and long-eared owls are among the smaller owls regularly found in its diet. Prey can weigh as much as the owl itself, and adult hares are among the largest regular victims.

Most hunting happens at dusk and before dawn. The owl watches from a perch, then glides down and seizes prey in its feet; small animals are swallowed whole and the indigestible fur and bones are coughed up later as pellets. Eagle-owls hunt more by sight than many owls, though their hearing is also excellent. For more on what different species catch, see what do owls eat?.

Behavior and calls

Eagle-owls are mostly nocturnal, active from the first hours after sunset to just before sunrise, and they spend the day roosting on a ledge, in a crevice or close against a tree trunk. In the far north, where summer nights are short and light, they also hunt in daylight.

They are famous for their voice. The male’s territorial song is a deep, resonant “oo-hu”, at a pitch of about 250–350 hertz, that carries for a long way across valleys. The female answers with a higher, slightly hoarse version, and pairs often duet. The German name Uhu and many other European names come from this sound. Calling is heard mainly from autumn to late winter, first to defend territory and then during courtship.

When threatened at close range, an eagle-owl fluffs out its feathers, spreads its wings into a wide arc, hisses and snaps its bill, making itself look even larger.

Breeding and life cycle

Pairs usually stay together for life and defend territories that typically cover about 15–80 square kilometers (6–31 square miles). The eagle-owl is one of the earliest-nesting birds in Europe: in the south, eggs may be laid from late January, and in the north from March or April.

Like all owls, it builds no real nest. The female lays her eggs in a shallow scrape on a cliff ledge, in a cave or crevice, on the ground between rocks or tree roots, or occasionally in an old nest of a large bird. The clutch is usually one to three white eggs, most often two, laid about three days apart; clutches tend to be larger in southern Europe, where rabbits are plentiful. The female incubates alone for 31–36 days while the male brings her food.

The gray, downy chicks grow quickly. They leave the nest at about 5–7 weeks, often walking out onto nearby rocks before they can fly, and make their first short flights at about 7–8 weeks. Their parents keep feeding them for several more months, and young birds become independent in autumn. They are able to breed in their second year but often wait until they find a free territory at 2–3 years old.

Lifespan and threats

The Eurasian eagle-owl is one of the longest-lived owls. Many wild adults live 15–20 years, and a ringed wild bird was recorded at about 27 years old. Captive eagle-owls can live for several decades. For other species, see how long do owls live?.

Healthy adults have almost no natural predators. The main causes of death today are human-made. Electrocution on power lines is the leading recorded cause of death in many European studies, followed by collisions with vehicles, trains, wires and wind turbines. Illegal shooting, poisoning and nest disturbance remain problems in some countries, and loss of prey such as rabbits can reduce breeding success.

Conservation status

The IUCN lists the Eurasian eagle-owl as Least Concern because it has an enormous range and a large total population, estimated in the hundreds of thousands of birds. The overall trend, however, is thought to be decreasing. In Europe there are an estimated 19,000–38,000 breeding pairs.

The European story is one of loss and recovery. Persecution wiped eagle-owls out of large areas in the 19th and 20th centuries, including the Netherlands, Belgium, Luxembourg and much of Germany. Legal protection, reintroduction projects such as the large release program in the Eifel region of Germany, and the insulation of dangerous power poles have helped the species return to many former areas, and it has spread back into the Low Countries since the 1990s.

Eagle-owls in Britain: native or not?

Eagle-owls lived in Britain in prehistoric times, but there is no reliable record of wild birds in historic times. Since 1996 a small number of pairs, estimated at a few dozen, have bred in northern England, Scotland and elsewhere. Most ornithologists believe they descend from escaped or released captive owls, which are popular in falconry and zoos, though a few people argue some may have flown from Scandinavia. Because of this uncertainty, the eagle-owl is not treated as a native British breeding bird, and its effect on native species is debated. The owls in the UK guide covers the five established species.

Myths and facts

Myth: the eagle-owl is the same bird as the great horned owl. The great horned owl of the Americas is a close relative in the same genus and fills a similar role, but it is a separate species and is smaller, averaging around 1.4 kg (3 lb).

Myth: eagle-owls hunt people. Eagle-owls do not treat humans as prey. A few birds, often captive-raised ones, have struck people who walked close to their nests, and it is wise to keep well away from any nesting owl. Anyone hurt by a bird should seek medical help.

Fact: an eagle-owl once stopped an international football match. In June 2007 an eagle-owl landed in Helsinki’s Olympic Stadium during a Finland-Belgium match, which was paused for several minutes. Finland’s national team has been nicknamed Huuhkajat, the Finnish name for the eagle-owl, ever since.