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Short-eared Owl

The Short-eared Owl (Asio flammeus) is a highly nomadic species that occurs throughout much of the world. This owl responds irruptively, on a broad geographic scale to high concentrations of small mammals. Consequently, the migrations and population status of the Short-eared Owl in North America are poorly understood. Populations have declined dramatically in the northeastern U.S. and there is evidence of significant long-term declines elsewhere. Concern over population declines and a lack of information on this species in Alberta have led to its inclusion on the 'Blue List' of species that may be at risk in the province.

The Short-eared Owl is typically associated with open areas that support cyclic small mammal populations, such as voles or lemmings. Habitats used throughout the circumpolar range of this species include arctic tundra, clear-cuts, peat lands, fresh and saltwater marshes, grasslands, cropland, and shrub-steppe. In Alberta, the Short-eared Owl is most often reported in the Grassland and Aspen Parkland Natural Regions.

The Short-eared Owl is one of the few species of North American owls that routinely nest on the ground. There is a definite tendency for the species to build nests on drier ground locations, especially relative to sites used by Northern Harriers.

The Short-eared Owl is so named because of the short, inconspicuous ear tufts on top of its head. The plumage varies from light brownish-orange to buffy white, with a whitish facial disk, darkly ringed eyes, and a dark wrist patch on the underwing. The specific name, flammeus, refers to the rusty or 'flame colored' plumage. Adults of both sexes are very similar, but the males are generally paler. This is a medium sized owl with males averaging 315 grams and females 378 grams.

Small mammals, particularly voles, dominate the Short-eared Owl's diet in North America. The extreme peaks that vole populations exhibit also make them a very attractive resource. Several studies have documented a high correlation between Short-eared Owl abundance and peaks in vole population cycles. In northern Europe, Short-eared Owl populations respond numerically and synchronously to fluctuations in vole density.

They hunt primarily on the wing, coursing less than 3 metres above the vegetation. They also hover at higher altitudes (up to 30 metres), essentially holding their position in the wind with limited wing movement. Less frequently, Short-eared Owls hunt from perches. Most hunting is done at night, but diurnal hunting may be required when adequate prey cannot be captured at night.

Short-eared Owl

Short-eared Owl

Short-eared Owl

Short-eared Owl