Burrowing Owl Biology

A Reference for North and Central American Owls

Name: Burrowing Owl – Athene cunicularia
Other Common Names: Florida Burrowing Owl (floridana); Western Burrowing Owl (hypugaea); Billy Owl; Prairie Dog Owl; Prairie Owl; Ground Owl; Howdy Owl.

Subspecies: There are two races of Burrowing Owl in North America. There is one race restricted to Clarion Island, south-west from the tip of Baja California and one race restricted to the Island of Hispaniola in the Caribbean. The remaining 15 recognized races are all found in South America.
A. c. hypugaea is found from E. Texas north to S. Manitoba and west across S. Canada and all of the Western USA south (including all of Mexico) to El Salvador.
A. c. floridana is restricted to Florida and the Bahamas (marginally S. Georgia).

Measurements and Weights:
Wingspan: 20 – 24 in.
Length: 9 – 11 in.
Tail: 2.8 – 3.4 in.
Average Weight: Male: 5.7 oz.
Average Weight: Female: 5.4 oz.

Description: The Burrowing Owl is a smaller owl that lacks ear tufts. The upper parts are brown with dull white to light buffy-brown spots. The spots are smaller and more numerous on the crown and larger on the back, upper wings and hind neck. It has a short tail with buffy white bands. The legs are distinctly long making it quickly distinguished from the other owls. The under parts are dull white with broad brown barring (all other small owls have streaking below) except the under tail coverts that are white. It has bold white eyebrows extending above and along the sides of the bill. There is a variable amount of white below the bill that may encompass the chin, throat, and entire lower facial disk although usually there is some brown on the chin. The Burrowing Owl’s eyes are lemon yellow and its bill is horn to cream colored.

Young: Juveniles lack the defined spots on the crown showing fine streaks only. The under parts lack barring and are dull white except the upper chest that is dark brown.

Habitat:

The Burrowing Owl’s unique home is, of course, a hole in the ground. These are usually burrows created by squirrels, prairie dogs, or other rodents and even turtles. Only rarely are they excavated by the owl itself (Florida). These are usually found in dry, level, open terrain such as prairie, plains, desert, and grassland with low height vegetation for foraging and available perches such as fences, utility poles, posts, or even raised rodent mounds. The abundance of available burrows seems to be a critical habitat requirement. Favored locations are those in relatively sandy sites (presumably for ease of modification and drainage), areas with low vegetation around the burrows (to facilitate the owl’s view and hunting success), holes at the bottom of vertical cuts with a slight downward slope from the entrance and slightly elevated locations to avoid flooding.

Food and Feeding:

Because the range and habitats vary so greatly, the availability of prey also varies for this owl. In general, the greatest biomass of food items taken consists of small mammals and numerically the majority of prey consists of invertebrates. Birds may be taken to a lesser degree. Reptiles and amphibians may also be an important prey. Of the invertebrate prey taken, the owl seems to especially prefer larger species such as grasshoppers, scorpions, large beetles, moths, and crickets. A vast array of small mammals also taken include mice, rats, voles, gophers, and even bats. Several birds may also be taken as may be possible and especially include Horned Larks but may also be as large as adult Mourning Doves. The owl may use a variety of hunting techniques as is appropriate for the prey and time of day. This may include hopping, walking, or running along the ground, fly catching, and hover/pounce. Prey is caught in the feet and may be transferred to the bill to carry or feed young. The owl tends to prey on insects during the day and small mammals at night.

Breeding:

The breeding season for the Burrowing Owl is from March to late August with the later dates from the northern part of its range. Clutch size ranges from 1 – 12 although averages about 7. The incubation period is from 28 – 30 days. The female does all the incubation and brooding and is believed to stay entirely in the burrow at this time while the male does all the hunting. The young fledge at 44 days but remain near the burrow and join the adults in foraging flights at dusk.

Movements and Life Span:

Only the northern populations seem to be migratory. The populations in the southern U. S. (California and Florida) are normally sedentary. Occasionally birds as far north as Washington and British Columbia will over-winter. In general the birds will stay resident when the food sources allow this and will disperse or migrate south in areas that food becomes scarce. The maximum life span recorded for a banded bird in the wild is about 8 1/2 years.