BIRDS
Status: Permanent Native Resident

GREAT HORNED OWL
(Bubo virginianus)

Description 

The great horned owl is a large owl about 22 inches (56 cm) in length. The ear tufts, which are feathers, give the appearance of horns, hence its name. The owl's color is mostly brown with some black markings and stripes. It has a white throat and yellow eyes. Males and females are of similar color, but there are darker and lighter forms. South Dakota is visited in the winter by the Arctic race of this species whose plumage is almost as pale as a snowy owl's. A great horned owl call is a series of 3 to 8 loud, deep hoots.

 
 
 
Distribution 

The great horned owl is a common permanent, native resident over the entire state of South Dakota. It lives in woodlands throughout the state, such as shelterbelts, parks, forests, urban forests, and along stream and river bottoms. In the winter, during times of low rabbit populations in Saskatchewan, some Arctic great horned owls move southward into South Dakota.

Natural History

The great horned owl is primarily nocturnal, which means it is active mostly at night. This species starts to nest early in the year in South Dakota, often laying eggs in late January and February with young fledging from the nest by May. The birds nest in trees, sometimes using an old nest of hawks, crows, or other birds. They also have been known to nest in tree cavities. Usually 2 or 3 eggs are laid in a nest. Great horned owls are predators that kill their prey with their large talons. They feed on cottontail rabbits, rodents, skunks, birds and other animals. Owls swallow their food whole and digest all but the bones, hair, and feathers, which they regurgitate in the form of a hard grayish or brownish pellet. These pellets often can be found under large trees. The presence of numerous pellets under one tree indicates the birds' repeated use of the same tree when eating. By studying the bones and skulls in the pellets, one can determine what the owl has been eating. All birds of prey make pellets, but because owls deposit numerous pellets in the same location, owl pellets are more easily found and studied than are those of hawks. A survey of more than 120 large owl pellets collected in Day County revealed that approximately 85% of the skulls in the pellets were from rodents. The remaining 15% came from shrews and moles, snakes, rabbits, and birds.

Conservation Measures

Owls, and all other birds of prey, are protected by law. It is illegal to harm them or to disturb their nests. It is also against the law to have in your possession any artifacts from birds of prey, such as feathers, talons or preserved specimens. Injured hawks and owls should be reported to the S.D. Department of Game, Fish and Parks or the U.S. Fish and Wildlife Service. Officials will arrange for birds that can be saved to be cared for at rehabilitation centers such as the Oahe Wildlife Center in Pierre or the Reptile Gardens Raptor Rehabilitation Center in Rapid City. (see below for educational information).

References
 

South Dakota Ornithologists' Union, 1991. The Birds of South Dakota, NSU Press, Aberdeen, SD 57401.
National Geographic Society, 1987. Birds of North America, Mead Paper Co., New York, NY.
Ehrlich, Dobkin, and Wheye, 1988. The Birder's Handbook, Simon and Schuster, Inc. New York, NY.

Selecsted Resources For Teachers
 

Oahe Wildlife Center, Pierre, SD. This non-profit center is run by Dr. Virginia Trexler-Myren, a veterinarian who provides wildlife
rehabilitation as well as educational programs at schools. These living bird and slide show programs are free locally, but may cost a
small amount away from the Pierre area. For information call 605-224-2984.
Reptile Gardens, P.O. Box 620, Rapid City, SD. This commercial tourist attraction provides group rates for class visits and
educational outreach programs on raptors and reptiles from November 1 through March 1. For information call 605-342-5873.

Written by:
Dr. Robert Buckman, Professor of Biology, Dakota State University, Madison, SD 57042. 1996.

Reviewed by:
Dr. Dan Tallman, Professor of Biology, Northern State University, Aberdeen, SD 57401.

Publication of the Great Horned Owl fact sheet was funded by the South Dakota Department of Game, Fish, and Parks, Division of Wildlife, Pierre, SD.