Eagle-owl females can span nearly two meters of wing
The Eurasian eagle-owl (Bubo bubo) ranks among the world's largest owls: females reach about 75 cm long with wingspans up to 188 cm, and males are slightly smaller. Striking orange eyes and ear tufts mark a mostly nocturnal hunter spread across a vast Eurasian range.
It is sometimes billed as the biggest owl on Earth, but the title is contested. Blakiston's fish owl averages slightly heavier and the much lighter great grey owl slightly longer, though the heaviest eagle-owls recorded by Heimo Mikkola matched the top fish-owl weight of 4.6 kilograms. It is smaller than a golden eagle yet larger than a snowy owl. Its wings are small for its weight, giving the highest wing loading of any European owl, so barn owls and short-eared owls are probably faster and more agile flyers.
Plumage is mottled blackish and tawny above and buff streaked with darker marks below, with barred wings and tail and legs feathered almost to the talons. At least a dozen subspecies are described, and colour varies widely; some European birds have blood-orange irises. Apart from size, the sexes look alike, though males' ear tufts reportedly stand more upright. Every feather is replaced annually in a moult running from July to December.
The owls favour rocky, mountainous country near woodland edges, shrubs or wetlands, and also coniferous forest and steppe, occasionally turning up in farmland and city parks. They hunt mostly rodents and rabbits, along with birds and larger mammals, and fall back on reptiles, amphibians, fish and big insects. A scrape on a cliff ledge or among rocks typically holds two to four eggs laid at intervals, so chicks hatch on different days. The female incubates while the male brings food, and both parents care for the young for about five months.
The range covers roughly 51.4 million square kilometres, with an estimated 100,000 to 500,000 birds. The IUCN rates the species least concern despite a falling trend. A small, arguably non-native British population, estimated at 12 to 40 pairs in 2016, has bred since at least 1996, and tame eagle-owls are sometimes used to scare gulls off nesting sites.
Source: Eurasian eagle-owl
