Bird of the Month: Burrowing Owl
By Andy McCormick
PC: Mick Thompson (Burrowing Owls)
Scientific Name: Athene cunicularia
Length 9.5 in
Wingspan 21 in
Weight 5oz (155 g)
AOU Band code BUOW
The diminutive Burrowing Owl is one of our most endearing birds. It can look a bit comical as it peers over the rim of its burrow entrance bobbing and twisting its head. Cowboys have called it the “Howdy Owl” in response to this behavior. One owl sensing danger can send a line of them down into the burrows for cover. The owls are active during both day and night and can often be seen perched on fence posts or on top of sagebrush. Their primary habitat is grassland with dry, sandy soil.
The Burrowing Owl is brown overall with white barring on the wing feathers. It has a round head with no ear tufts and the bright lemon yellow eyes are set in separate oval disks. “The combination of ground-dwelling diurnal habits and small size render this owl nearly unmistakable. The most distinctive features include long legs and a characteristic of bobbing up and down when disturbed” (Poulin, et al).
The bird is in the genus Athene, for the Greek goddess to whom owls were sacred, and the species name cunicularia, is from Latin for a miner, or a tunnel or burrow (Holloway). The western subspecies hypugaea is common, and floridana, is a smaller subspecies found in Florida (Alderfer).
Burrowing Owls in the northern portion of their range, which extends into southern Alberta and Manitoba, begin fall migration in late August. Some Washington birds, typically those in more urban areas, will overwinter in the breeding area. Many Burrowing Owls are resident in the southwestern U. S. and others migrate there and into southern Mexico.
The owls arrive on the breeding grounds in Washington in late March and nest in small colonies of 10-12 individuals in burrows previously dug by a prairie dog, ground squirrel, marmot, skunk or other burrowing mammal. It appears the owls are dependent on these mammals for the burrows which are typically 6-10 feet in length with a larger chamber at the end. The nest is lined with dried animal dung. Usually 7-10 eggs are deposited and incubated by the female for about one month. The female stays with the young at first with the male bringing food. First flight occurs in about six weeks (Kaufman).
Burrowing Owl populations have dropped by over 40% in the past 50 years and in some areas of previous abundance have now become rare. This is primarily due to eradication of prairie dog colonies and human development for agriculture and housing in grassland areas. These owls have a juvenile survival rate of only 20-30% in the first year. Badgers are a major predator and remains of Burrowing Owls have been found in a number of different hawks and falcons. Snakes, skunks and dogs raid nests for eggs. There have also been reports of cannibalism within nesting colonies (Poulin, et al). Conservation efforts have focused on preserving some prairie dog habitat and placing artificial burrows in safe areas.