Burrowing Owl

Common Name: Burrowing Owl
Class: Aves
Order: Strigiformes
Family: Strigidae
Genus: Speotyto cunicularia

One of the joys of visiting the western United States was the possibility of seeing a Burrowing Owl, one of the rarest birds that lives on the American prairie. This animal makes its home in prairie dog towns, living in abandoned burrows. Expansion by people into the prairie has caused a decline in prairie dog communities and without these towns burrowing owls have a shortage of homes to nest and lay their eggs. Continuation of this trend may eliminate burrowing owls completely.

Burrowing Owl Taxonomy/Description

The burrowing owl belongs to the owl family, Strigidae, in the Avian Order Strigiformes. Its scientific name is Speotyto cunicularia, derived from the Greek words "speo", meaning cave and "tyto", meaning owl, and the Latin word "cunicularus", meaning little miner.

The upper body of the burrowing owl is brown, mottled with off white spots. The remainder of the body is white with dark brown barring. Its legs are long, and the fronts of the legs are feathered. The burrowing owl possesses a white facial disc and yellow irises. The sexes are similar in appearance.

Burrowing Owl Habitat/Diet

The burrowing owl can be found on open, treeless prairie in western North America down through South America. Isolated populations are also located in Florida and the Caribbean. The burrowing owl makes its home in the discarded burrows of prairie dogs, woodchucks, viscachas, wolves, foxes, skunks, badgers, armadillos and gopher tortoises.

Burrowing owls eat insects, small mammals (including young prairie dogs), lizards, snakes, frogs and scorpions.

Burrowing Owl Behavior/Reproduction

Burrowing owls are diurnal. They make their homes in the abandoned burrows of other animals. The owl may or may not enlarge these burrows as needed when they move in. As a last resort, if no abandoned burrows are available, burrowing owls sometimes dig their own. These owls tend to gather in colonies of 10–12 pairs in a 2–3 acre area. However, they are sometimes found in isolated pairs.

Burrowing owls will decorate their burrows with bits of cattle or bison dung and other materials in order to camouflage their nests from predators. In urban areas, they have been known to use garbage and cigarette butts.

Burrowing owls can often be found perched on rocks, fence posts or branches. Perches improve the owl’s ability to spot their prey as well as predators which may harm them. Perching also enables the owl to elevate itself from the extremely hot ground of the midday summer prairie. When overheated, burrowing owls might also drop their wings to shade their legs, a form of thermoregulation.

Burrowing owls demonstrate a unique defense against predators: when threatened, both young and adult owls hiss from inside their burrows – imitating the sound of a rattlesnake to deter the predator from entering.

Burrowing owls reach sexual maturity at one year of age. Nesting generally occurs between March and July. The female owl lays 6–11 pure white eggs (usually 8 or 9) in a chamber at the end of a burrow. Both parents incubate the eggs for approximately 28 days.

Burrowing Owl History

Burrowing owls were once also found in several islands in the West Indies. But they disappeared at the end of the nineteenth century following the introduction of the mongoose.

Our Experiences with Burrowing Owls


photo M. Noonan

We were fortunate enough to have several encounters with Burrowing Owl while out in South Dakota. We first spotted a Burrowing Owl at a great distance while making observations in a prairie dog town at Buffalo Gap National Grasslands. Days later, we were able to accompany Randy Griebel (a graduate student from the University of Nebraska) who was studying the Burrowing Owl population of Buffalo Gap National Grasslands. He took us to an abandoned prairie dog burrow that was being used as a nesting site for a pair of burrowing owls. With his help we were able to observe the eggs using fiber-optic camera equipment.

 

Burrowing Owl Conservation

The greatest threat to the survival of the burrowing owl is loss of habitat due to human activity. Alteration of the prairie for agricultural purposes results in a serious reduction in available habitat. The large-scale destruction of prairie dog colonies also significantly reduces the availability of suitable habitat.

Glossary:

diurnal - active during the day

thermoregulation - an organism's ability to maintain its body temperature within certain boundaries when the surrounding temperature is different
 

Content provided by Canisius College students under the direction of Michael Noonan, PhD.