USGS Home
Contact USGS
Search USGS

Platte River Status: A fairly common permanent resident throughout the study area.

Breeding Range: A fairly common widely distributed nesting species in the Platte River Valley and on the Eastern Plain; uncommon and more localized on the Dissected Plain, Western Plain, and in the Sandhills.

Breeding Population: The estimated population of 2,500 breeding pairs in 1979-1980 made up about 0.1% of the total bird numbers those years.

Habitat: Mean breeding densities in upland prairie and lowland forest were 0.2 pairs per km². We located several nests in shelterbelts and tree plantings as well as in a cemetary. Faanes and Andrew (1983) reported that nesting season great horned owls on a northeastern North Dakota study area were located at the edge of bur oak - green ash forest. Rising (1974) stated that in western Kansas, great horned owl was a common resident in woodlands and canyons.

Effect of Habitat Alteration: Great horned owls have been positively impacted by encroachment of wooded vegetation within the Platte River channel, and by establishment of shelterbelts and other tree plantings in the uplands.

Nesting Data: We have located 13 active nests in the study area. Egg dates extend from 21 February to 28 March at the Mormon Island Crane Meadows, Hall County. Hatchlings were observed in 3 different nests there during 28-30 March. Nestlings have been observed as late as 16 May. Egg dates in North Dakota range from 8 March to 5 May, while those in Kansas extend from 11 January to 20 March (Johnsgard 1979).