Short-eared Owl

Description
The Short-eared Owl is a medium-sized, buffy-white owl with very short ear tufts. The upper parts are broadly but softly streaked. Brown streaks on the abdomen are narrow and more sharply defined. Flight feathers and tail are barred with brown. It has poorly defined blackish areas, which frame the owl's yellow eyes. The owl displays a black patch near the wrist under the wing in flight. It is more buffy than the Long-eared Owl, with no cross-barring on its abdomen.

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Approximate range - not for legal use

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Distribution and Population
The Short-eared Owl breeds or winters in North, South and Middle America, Europe, Asia and Africa, for a nearly global range. In Canada, it breeds in every province and territory, from the southern border to the low Arctic. It is absent from the Boreal Forest and other heavily forested areas. In the winter it withdraws from the northern parts of its range, and remains only in the southern parts of most provinces.

The historical distribution of the Short-eared Owl is probably similar to today's. The owl was likely found in open habitats and marshlands of southern Ontario, Quebec, British Columbia, Newfoundland and the Maritimes. Larger populations probably occurred in the Prairies and across the north. Forest clearing in eastern Canada created new habitat, allowing populations to increase. Destruction of marshes and native grasslands, coupled with intensive agricultural practices, resulted in the species' decline. During the 20th century, population sizes were thought to have decreased in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario and Quebec. However, they remained stable in Newfoundland, Labrador and the Maritimes. The owl now occurs in small numbers throughout its Canadian range. Exact numbers are not known.

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Habitat
The owl prefers extensive stretches of relatively open habitat. It is primarily a bird of marshland and deep grass fields. It likes to hunt and roost in abandoned pastures, fields, hay meadows, grain stubble, airports, young conifer plantations and marshes in the winter. It frequents prairies, grassy plains or tundra in the summer.

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Biology
Atypically for an owl, the Short-eared Owl builds a new nest instead of claiming an abandoned one. Nests are usually slight depressions in the ground. In Ontario, some nests are cups of dried weeds or flattened grasses. Nests are often hidden under low shrubs, reeds and grasses, and are often located near water. When prey is plentiful, the breeding season begins sooner, and the clutch size is larger. Canadian populations usually raise one brood per year. Females may renest if nests or eggs are destroyed. The average clutch size is 5 eggs, but clutches of 4-14 eggs have been recorded. The young leave the nest at 24 to 27 days. Breeding begins at one year or younger. The species roosts in grass fields where its plumage blends in. The owl is nomadic, and wanders extensively within its winter and breeding ranges hunting for prey. In areas with lots of prey, individuals congregate and roost in groups in the winter. In the winter of 1984-85, 300-400 birds were reported at Toronto's Pearson International Airport. Most congregations consist of fewer than 10 birds. Like other raptors, the owl tends to flush from the nest at the last minute when approached. It has been known to attack human intruders near the nest, but will usually rely on distraction tactics, such as circling overhead using deep wing-beats or playing out its broken-wing act.

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Threats
Large-scale destruction of native prairie grasslands has been particularly hard on this species. Natural succession, wetland drainage, urban expansion and increasingly intensive farming have contributed to its decline. The species is exposed to danger from predators and agricultural machinery since it nests on the ground. Effects of environmental contamination are not known. Shooting, collisions with aircraft, trains, cars, barbed wire and farm machinery are added factors. The species' attraction to open airport habitats is another problem.

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Protection
Species that were designated at risk by COSEWIC prior to October 1999 must be reassessed against revised criteria before they can be considered for addition to Schedule 1 of the Species at Risk Act (SARA). To find out when re-assessment of this species is anticipated, please consult the COSEWIC web site.

The Short-eared Owl is not protected by the federal Migratory Birds Convention Act, but provincial legislation in most provinces protects it from hunting, possession and selling. Considerable sums are spent keeping this species and others away from airport runways.

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References
- Cadman, Michael D. and Annette M. Page. 1994. Status Report on the SHORT-EARED OWL, Asio flammeus, in Canada. Committee on the Status of Endangered Wildlife in Canada. 60 pp.

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