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STRIX OCCIDENTALIS

APPEARANCE

Robust, medium-size, with round head, no ear tufts, and relatively long tail; upper parts dark brown with pale spots; under parts graduate from brown and whitish barring on upper breast to heavy white spotting lower down; flight feathers and tail heavily barred; eyes dark brown/black in buff facial disk with dark rim.

SIZE

length 17 in. (43 cm)

weight 1.3 lb (600 g)

wingspan 45 in. (114 cm)

females larger than males

DISTRIBUTION

Pacific North America, from southwestern British Columbia south through western Washington and Oregon to southern California; also Rocky Mountains, from southern Utah and Colorado south through Arizona and northwestern Texas into central Mexico.

STATUS

Near Threatened

“MY FRIENDS, IT IS TIME to consider the human factor in the Spotted Owl equation,” said U.S. President George Bush, addressing lumber employees in Colville, Washington State, in 1992. And so, this threatened bird became a political football: symbolic of the struggle between loggers, who felt its conservation threatened their livelihoods, and environmentalists seeking to save the old-growth forests of the Pacific Northwest. The bird in question is, in fact, one of the more mild-mannered of its kind. Despite belonging to the same Strix genus as the notoriously feisty Tawny Owl and Ural Owl, it is surprisingly tame and shows no appetite for defending its territory. Unfortunately, its territory is under serious threat as the forests continue to disappear.

The Spotted Owl resembles the slightly larger Barred Owl, the two having diverged from a common ancestor some six to eight million years ago. Its plumage is a complex patterning of spots and bars, and the dark brown eyes sit in a buff facial disk with a dark rim. This owl inhabits mountains and humid coastal forest, and its intricate patterning provides camouflage against the dappling shadow in the Douglas fir forests of the northwest. Elsewhere, it frequents mature hardwood forests of oak, alder, and cottonwood. Whatever the forest type, it prefers a multilayered canopy and tends to choose steep-walled valleys, generally with water nearby.

This species roosts by day on a high branch against a tree trunk, and hunts from shortly after sunset to just before sunrise. Top of the menu are wood rats and flying squirrels, with pocket gophers, rabbits, and a variety of other small mammals also taken. It may also capture birds, sometimes in flight, as well as snakes, crickets, beetles, and moths. This owl has even been observed walking around a campsite picking up scraps. In good times, surplus prey is cached for later.

The Spotted Owl forms monogamous pairs that maintain a year-round bond. In early spring, the male advertises his territory with a mellow four-syllable hoot: “whoop, wu-hoo, hu.” The female responds in kind, and the two call together in courtship. Among various other barks, grunts, and chattering calls, the female uses a piercing “coo-weep,” reminiscent of a Tawny Owl, to contact her mate. Breeding depends upon prey abundance and does not happen every year. The pair generally chooses an old stick nest, typically that of a northern goshawk (Accipiter gentilis), but may also use mistletoe, broken treetops, and cavities in banks and rock faces. On average, the female lays a clutch of two to three eggs, and the chicks hatch at twenty-eight to thirty-two days.

In the wild, the Spotted Owl may live seventeen years. Juveniles suffer high mortality (up to 90 percent in some regions) and must dodge forest predators such as the Great Horned Owl and red-tailed hawk (Buteo jamaicensis). The species’ greatest threat, however, comes from the loss of its habitat, and the attempt to save these forests has made the Spotted Owl a conservation icon. Furthermore, modern logging practices often benefit the larger and more aggressive Barred Owl, against which the Spotted Owl cannot compete. With a total population estimated at 15,000 birds, the species is classed as Near Threatened. It is declining across most of its range, with the Canadian population reduced to fewer than one hundred breeding pairs. “Shoot an owl, save a logger,” was once a popular bumper sticker. Unless this heavy decline is reversed, there may soon be no owls left to shoot.

A Barred Owl stretches one wing to reveal the markings for which it is named.