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ATHENE CUNICULARIA

APPEARANCE

Small, with round head, long legs, and upright stance; pale yellow eyes, brownish facial disk, white eyebrows and white throat band; under parts pale to brownish, spotted in white and dusky-brown; upper parts and crown brown with whitish streaks and dots; short tail and barred, rounded wings.

SIZE

length 7.5 – 11 in. (19 – 28 cm)

weight 4.9 – 8.5 oz (140 – 240 g)

wingspan 20 – 24 in. (50 – 61 cm)

female slightly larger than male

DISTRIBUTION

In North America, all states west of Mississippi Valley, north to southern Canada, and south into Mexico and Florida; also in South America, Central America, and the Caribbean; birds from northern North America migrate south to Mexico and Central America.

STATUS

Least Concern

IF EVER A BIRD WAS DESTINED to feature in a cartoon strip, it is this charismatic little owl. Typically, it appears from a hole in the ground, stands tall on stilt-like legs, bobs its head up and down, and fixes you with a furious glare. Small wonder that the Burrowing Owl continually pops up, so to speak, in children’s fiction, recently as a band of Mexican Mariachi musicians in the animated movie Rango (2011).

This is the most terrestrial of the world’s owls: it not only spends much of its time on the ground, but also, as the name suggests, nests beneath it. Although capable of digging its own burrow, this owl generally reappropriates the burrow systems of ground-dwelling mammals, such as prairie dogs (Cynomys). The two are often seen in close proximity and inhabit the same terrain: open grasslands, from the prairies of North America to the pampas of South America. Other favored habitats range from semidesert to pinyon and ponderosa pine scrub, and this owl will happily take to farmland and other human landscapes, too, including golf courses and airports, if conditions are suitable.

The Burrowing Owl is one of the most widely distributed owls in the Americas. However, it avoids mountains and forest. In South America, for example, it is found discontinuously in all suitable habitat as far south as Tierra del Fuego, but is absent from the Amazon Basin and the high Andes. Birds toward the north of the North American range are migratory, but the South American population is largely sedentary.

This species was once assigned its own genus, Speotyto. Today, most taxonomists group it within Athene, along with Eurasia’s Little Owl, which it closely resembles. The fragmented distribution has produced up to twenty-two subspecies, with the nominate race, A. c. cunicularia, found on the eastern side of South America. These vary in markings, but the Burrowing Owl’s distinctive habits and posture—small, round head and long-legged silhouette atop an anthill or fence post—mean that confusion with other owls is unlikely. In fact, it is one of the easier owls to observe up close; it is both diurnal and reasonably approachable, especially where it is used to human disturbance. A good view reveals pale yellow eyes set in a brownish facial disk. The strong white throat band stands out above a brownish upper breast, which is spotted in white to differing degrees according to subspecies. The tarsi are long and white, the tail is short, and the heavily barred wings appear broad and rounded in flight. Males are generally lighter in color, especially toward the end of the breeding season, when their guard duties outside the burrow expose their plumage to the bleaching of the sun.

The Burrowing Owl is seldom seen far from its burrow, and often perches at the entrance or on a nearby perch. When alarmed it will bob up and down excitedly, and if threatened it will fly away low, with irregular, jerky wingbeats between long glides. Although visible throughout the day, the bird becomes most active at dusk. Its prey changes with season and location, but the staple diet in most areas is large arthropods, including beetles, grasshoppers, and scorpions. However, this owl will also turn to small vertebrates, from reptiles and amphibians to small mammals, as well as birds up to the size of the eared dove (Zenaida auriculata), which is its equivalent. Birds in different areas specialize in a particular food type: in southern Brazil, for example, the delicate vesper mouse (Calomys tener) is a favorite. The usual hunting technique is to watch for prey, then glide silently toward it and snatch it from the ground with talons. However, the Burrowing Owl is a versatile little predator and will also chase insects on foot or hawk them in midair. When feeding young, it may hunt around the clock.

In the northern hemisphere, courtship starts in March and April. Generally, this species forms monogamous pairs, although polygyny—one male mating with and providing for two or more females in separate burrows—is occasionally recorded. Activity starts with the male’s distinctive two-syllable call, a hollow “cu-cuhooh.” This song varies according to individual and mood. The female’s call is similar but higher, and both sexes have a repertoire of harsh and curious calls. The male backs up his vocal performance with a choreographed courtship display, in which he coos, bows, and scratches the ground, flashing his prominent white throat and eyebrows. He may also rise in a brief hovering display flight, hanging above the female, then flying in a circle around her.

A pair will return to the same nesting burrow, or one close by, for many years in succession. Once settled, the female lines the burrow with dry material, including cattle dung. Indeed, the pair will often deposit dung outside the burrow entrance: once thought to be a means of repelling predators, this is now believed to encourage dung beetles and other insects on which the owls can feed. The female lays six to nine eggs (a maximum of twelve), one day apart, which she incubates for twenty-eight to thirty days. The male, meanwhile, provides food and aggressively defends the small area around the burrow.

In productive habitat, the Burrowing Owl may form loose colonies. This enables it to cooperate in sounding the alarm and warding off predators. Another ingenious defense system is deployed by the young chicks in the burrow: if disturbed, they make a harsh alarm call that sounds uncannily like the warning rattle of a rattlesnake. This is a prime example of Batesian mimicry, in which a vulnerable animal imitates a more dangerous one in order to deceive a potential predator. And this species certainly has many predators, from larger owls and other raptors to badgers, skunks, armadillos, and even domestic cats and dogs.

Globally, the Burrowing Owl is classed as Least Concern, with an estimated population of two million individuals. However, its wide distribution belies the fact that it is declining in many areas. Today, it is endangered in Canada, threatened in Mexico, and of special concern in Florida. Among the threats it faces are the loss of habitat to agricultural intensification, pesticides, and control programs for prairie dogs. Conservationists try to relocate Burrowing Owls whose burrows are threatened by a development project by enticing them to new burrows and perches constructed on safe alternative quarters nearby.

Burrowing Owls often find a home in human environments.

A Burrowing Owl drives an American Badger away from its nesting burrow.

Frogs feature among a wide variety of prey for this species.

The Great Horned Owl held an iconic status among the native peoples of North America.