Long-eared Owl – Asio otus
Order Strigiformes
Genus Asio – eared owls
Long-eared owls, Asio otus, are medium-sized, nocturnal birds of prey found across Europe, Asia, and North America, belonging to the eared owl group. They are easily recognised by their slender build, long, upright ear tufts, orange eyes, and mottled brown and buff plumage which provides excellent camouflage among trees. Despite their name, the “ears” are actually feather tufts used for display and camouflage rather than hearing. Their facial disc is well defined, helping to funnel sound toward their ears.
Long-eared owls inhabit woodlands, forest edges, and areas with dense tree cover, often near open land such as grasslands or farmland where they hunt. Adults typically measure around 13–16 inches in length with a wingspan of approximately 3–3.5 feet, and weigh between 7 and 15 ounces, with females slightly larger than males, demonstrating mild sexual dimorphism. They are partially migratory, with some populations remaining resident while others move south during winter.
They are specialised hunters of small mammals, particularly voles, which make up the majority of their diet, though they will also take small birds and insects. They hunt primarily at night using silent flight, exceptional hearing, and keen night vision, often flying low over open ground in search of prey. Their asymmetrical ear placement allows them to locate prey with remarkable accuracy, even in complete darkness.
Long-eared owls do not build their own nests, instead using abandoned nests of other birds such as crows, magpies, or hawks, usually located in trees. The female typically lays 3–5 eggs, with the male providing food while she incubates, and both parents caring for the young after hatching.
Did you know long-eared owls often roost communally during the winter months, gathering in groups in dense trees for warmth and protection, sometimes with dozens of individuals in a single roost? This behaviour makes them easier to spot in winter than during the breeding season.
They have excellent night vision and highly developed hearing, allowing them to detect even faint movements in darkness. Like other owls, they can rotate their heads up to 270 degrees, giving them a wide field of view without moving their bodies.
SUPER FACT
EVOLUTIONARY ORIGINS
Owls of the genus Asio evolved as specialised nocturnal hunters of open landscapes, developing long wings for buoyant flight, acute hearing for detecting prey in low light, and cryptic plumage for concealment. The long-eared owl represents a highly adapted small-mammal specialist within this lineage, perfectly suited to hunting in grassland and woodland-edge environments.