Associated Species: Other species that may use habitat in a similar way and/or respond similarly to threats, management, and conservation activities include Northern Harrier, Barn Owl, and a variety of waterfowl.

Distribution: Short-eared Owls' breeding range is circumpolar in the northern hemisphere, primarily above 40 degrees north latitude. Northern populations withdraw in the winter, but they are residents through the year in mid latitudes. The southern states and Mexico host wintering birds. They also reside in the unforested regions of South America. These owls are sparsely and widely distributed in Colorado, with more birds present in winter than in summer. Breeding birds are most common on the northeastern plains, in North Park, and in the San Luis Valley. Browns Park NWR has also reported this species as an occasional breeder. Records indicate that they have never been common breeders in Colorado (Boyle 1998).

Habitat Requirements: These owls breed and forage in grasslands, prairies, wetlands, and croplands. In Physiographic Area 87, almost all nesting takes place in wetlands. Large blocks of suitable habitat (100 ha; 250 ac) seem necessary to support breeding pairs, and only the San Luis Valley has sufficient quantities to host a stable population.

Ecology: Short-eared Owls nest on the ground, usually on a dry site, often elevated on a small hummock. They are rare among owls in that they construct their own nests. In Colorado, they begin nesting in April or May, incubating for 26-28 days and brooding young on the nest for 31-36 days. Most young fledge by mid July or early August. Fall migrants arrive in September and October and leave in March. Short-eared Owls eat small mammals (especially voles, Microtus spp.) and occasionally small birds.

Management Issues and Conservation Recommendations: Habitat management schemes for nesting waterfowl and upland gamebirds generally benefit Short-eared Owls. Consider the needs of this species when managing for game species. Populations of the principal prey species (voles) should be maintained at levels compatible with economic activities on the land.

Status and Reasons for Concern: This species is not globally threatened, but is declining in much of its range due to drainage of wetlands, intensification of agriculture, persecution, rodenticide poisoning, urbanization, and traffic mortality (del Hoyo et al. 1999). It is on the national Watch List, indicating a high conservation need throughout its range in North America, where populations have declined in many areas. It is considered the rarest and most threatened owl in the Northeast, and several northwestern states have also reported significant declines. The Short-eared Owl is not adequately monitored by the BBS within Physiographic Area 87, and the data are too sparse to allow meaningful analysis of trends. This species is monitored by MCB with nocturnal surveys.

Biological Objective: Increase the species' distribution and abundance, as measured by results of MCB and other monitoring programs.

Selected References: Andrews and Righter 1992, Clark 1975, del Hoyo et al. 1999, Holt and Leasure 1993, Kingery 1998.