A Parliament of Owls. David Tipling
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.
BARRED OWL
STRIX VARIA
APPEARANCE
Medium-large owl with wide, rounded head, dark eyes, yellow bill, and no ear tufts; pale gray-brown facial disk indented at top and bottom; plumage largely grayish-brown; upper parts barred with white and spotted on wing coverts; pale under parts densely barred on upper breast and more finely streaked below; flight feathers heavily barred. size
length 19 – 22 in. (48 – 56 cm)
weight 1.1 – 2.3 lb (500 – 1,050 g)
wingspan 42 – 44 in. (107 – 111 cm)
females larger than males.
DISTRIBUTION
Eastern North America, from southern Canada to Florida and south to southern Mexico; range expanding in northwestern United States; northerly populations make irregular southward migrations.
STATUS
Least Concern
IT IS NOT OFTEN THAT THE GOOD FORTUNES of one owl species spell misfortune for another. However, the advance of the Barred Owl in the northwestern United States—following a trail blazed by the loggers—is giving conservationists a headache, because it may be at the expense of the much rarer Spotted Owl. The two species belong to the Strix genus, but the Barred Owl is larger and more aggressive. In the past, the Spotted Owl was secure in the large, untouched tracts of forest in the northwest, while the Barred Owl flourished further east. However, the logging and fragmentation of these northwestern forests have produced a forest structure better suited to the Barred Owl. The more common species has been quick to accept the invitation, ousting its cousin in the process.
Four subspecies of the Barred Owl are recognized, of which the nominate race, S. v. varia, is the largest and most northerly, occurring from southeast Alaska to North Carolina. This bird frequents moist, dark, mature forests, typically in wooded swamps or woodland fringing lakes. It thrives in large parks with old trees and will take to old-growth forest where this has been opened up by logging. It is a nocturnal species that hides away by day in dense foliage, usually close to a tree trunk. Here, it can escape the attentions of the irate songbirds that are often drawn to mob it. After dark, however, this owl need fear no such persecution. Like most Strix species, it is largely a sit-and-wait hunter, watching and listening from its high perch, then swooping down to grab the prize. Prey comprises small rodents, notably meadow voles (Microtus pennsylvanicus), but it may take larger mammals, including possums and weasels. It hunts birds, such as jays and pigeons, by ambushing them in flight as they settle at their roost, while smaller owls, including the Eastern Screech Owl (Megascops asio) and Long-eared Owl, also sometimes fall victim. Among other interesting observations, this species has been seen wading in shallows to capture fish, plucking baby alligators from swamps, and visiting campfires to capture large insects drawn to the light. At peak nesting, it may also hunt by day.
The Barred Owl is easily identified by its territorial call: a resonant “hoo, hoo, too-HOO; hoo hoo too-HOO, ooo” phrase. A male tends to repeat this call in bursts of eight and then fall silent, waiting for a female’s reply. Once the two meet, the male pursues the female, giving a variety of calls and displays, swaying on a branch and sidling up to her with wings raised. This is a very vocal species, and the pair communicates throughout courtship with hoots, yelps, barks, and monkey-like shrieks, cementing their bond with feeding and mutual preening. Unpaired birds may call in fall, but an established pair does not get going until late winter. The pair usually selects an old stick nest from a hawk, crow, or squirrel but may also choose a natural cavity. The female lays two to four eggs and incubates them for twenty-eight to thirty-three days while the male provides food. The parents care for their chicks for four months, longer than most owls.
In captivity, the Barred Owl has been known to live thirty-two years. With an estimated population of 600,000, it is classed as Least Concern. Indeed, its recent range expansion in the northwest is a worry for conservationists, who fear the impact on the Western Screech Owl and rare Spotted Owl. In a contentious initiative of the U.S. Forest Service, considerable numbers of Barred Owls have already been culled.
A