Short-eared owls, often affectionately referred to as “shorties” or “SEOs”, are medium-sized owls with a mottled brown body, pale under-wings and striking yellow eyes that betray this as a daytime hunter. Increasingly, this species seems to be overwintering in Britain, when before most either migrated to the north English moors or to continental Europe – as an amber listed species, this is good news.
That which follows is a summary of Short-eared owl natural history. The detailed article for this species will follow in due course.
The Short-eared owl at a glance
Seven recognised subspecies; type species Asio flammeus flammeus found in UK.
Size: Medium-sized owl, standing 34-42cm (13-16in) tall; weighs 200-500g (7-18 oz.) with males lighter than females. Wingspan 21-34cm (8-13in) and tail 13-16cm (5in). Males weigh up to 400g (14 oz.), with females up to 500g (1 lb).
Colour/Appearance: Mottled black/brown/buff bodies, with paler underside and under-wing. Striking yellow eyes.
Distribution: Resident in eastern Scotland, most of northern, northern-central England and parts of eastern England and northern and western Wales. Winter visitor to southern and western Wales, most of central England, southern and eastern Ireland. Summer visitor to much of Scotland. RSPB estimate 1,000 to 3,500 UK breeding pairs and 5,000 to 50,000 continental individuals wintering in the UK, largely continental immigrants.
Longevity: Reasonably long-lived bird, attaining up to 13 years in the wild.
Sexing: Females larger than males and calls sexually distinctive.
Activity: Mostly diurnal (often seen hunting during the daytime), with activity peaks at dawn and dusk. Often perches on exposed sites (fence posts, bushes etc.). Highly migratory species, sedentary only in tropics./p>
Territory/Habitat: A bird of farmland and, especially in winter, coastal marshes and wetlands. Prefers open areas, with sparsely distributed trees and bushes; can do well in heavily cultivated areas. Establishes territory during breeding season and may construct nest; display in flight with wing-clapping and diving. Territory varies greatly with food availability between 18-137ha (up to 13. sq-km or half a sq-mile).
Diet: Small mammals, predominantly voles, although will take rabbits and rats as well as some predatory mammals (e.g. weasels). Also takes frogs, lizards and medium-sized birds (up to size of pigeon); may cache surplus food in vicinity of nest.
Reproduction: Breeds in late-winter/early-spring; lay 7-10 eggs between late-March and June. Female incubates while male hunts, incubation lasts 26-29 days and chicks leave nest to hide in vegetation at around 16 days old (flightless). Parents continue to feed chicks, which sexually mature in their first year.
Behaviour and Sociality: May gather in groups during autumn; roost and hunt together. During breeding season will fiercely evict intruders from territory. Male emits rapid series of deep ‘boo-boo-boo’ hoots (rising and falling in pitch and volume and likened to puffing of a steam train); both sexes give ‘kweeau’ calls when disturbed. Aggressively defends nests.
Threats: Amber conservation list species. Crows known to raid nests for chicks and eggs, which can impact breeding success locally, and adult birds occasionally fall prey to peregrines. Often ground-nesting, which leaves nest vulnerable to accidental damage (e.g. crushing by farm machinery).
Nick Baker’s British Wildlife: A month by month guide - by Nick Baker
New Holland Publishers -- 2003 -- ISBN: 978-1845171131
Wild Animals of Britain & Europe - by Helga Hofmann
HarperCollins Publishers -- 1995 -- ISBN: 978-0007627271