Identification

Perching: About 10" tall with long spindly legs. Perches on prairie dog mounds, fence posts, and on the ground. Brown to buff colored.

Flying: Flies low to the ground, usually in a straight line. Sometimes hovers into the wind. Stout body and wide, rounded wings distinguish it from meadowlarks and other songbirds.

Nesting Habitat

Rodent colonies in grasslands, shrublands, and deserts, mostly below 2000 m. Highest nesting densities occur in prairie dog colonies on the eastern plains. Burrowing owls avoid areas where mid- to tall grass obscures their view of terrestrial predators. Occupied nest burrows usually have whitewash on the burrow mound, and bits of bone and fir of prey items are often scattered around the burrow entrance.

Nesting Dates

Courtship: mid-April to mid-May

Incubation: early May to mid-July

Dependent nestlings: mid-May to early August

Incubation of 6-11 eggs requires 27-30 days. Young appear above ground after about two weeks and fledge (moving to separate burrows) about 40-45 days after hatching. Number of young appearing above ground averages 3-5.

Statewide Distribution and Population

Nests throughout eastern plains, in some western valleys (primarily the Grand Valley area), northwestern Colorado, and in scattered mountain parks. Negative influences on populations to loss of nesting habitat (primarily active prairie dog colonies on the high plains), fragmentation of nesting habitat leading to increased predation by urban-edge predators, automobile collisions, and poisoning of insect prey in Mexico.

State and Federal Status

State threatened; Colorado State Wildlife Action Plan Tier 1 species.

Search and Nest Monitoring Protocol

For rodent colonies of 50 acres or less: Beginning in mid-May, observe each colony for a minimum of 30 minutes from a stationary observation point, scanning the colony every 5 minutes with binoculars or a spotting scope. Repeat at two-week intervals until 1 August or until all young have dispersed from the nest burrow.

For rodent colonies larger than 50 acres: Same as above, but locate multiple observation points as necessary to provide a clear view of all areas of the colony.

Recommended Nest Buffer Areas

No foot traffic or recreational activity within 50 m of active nest burrows, 1 April-15 August.

References

Johnsgard, P. A. 1988. Owls of North America. Smithsonian Institution Press, Washington, D.C.

Kingery, H. E., ed. 1998. Colorado breeding bird atlas. Colorado Bird Atlas Partnership, Denver.

Pezzolesi. L. S. 1994. The western Burrowing Owl: increasing prairie dog abundance, foraging theory, and nest site fidelity. M. S.. Thesis, Texas Tech University, Lubbock.

Plumpton, D. L., and R. S. Lutz. 1993. Prey selection and food habits of Burrowing Owls in Colorado. Great Basin Naturalist 53: 299-304.

Vroos, K. 1988. Owls of the Northern Hemisphere. MIT Press, Cambridge.

Walker, L. W. 1974. The book of owls. Alfred Knopf, New York.

Wickersham, L.E. 2016. The Second Colorado Breeding Bird Atlas. Colorado Bird Atlas Partnership, Denver.