Barred Owl

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Image:BarredOwl.jpg

Common Name: Barred or "Hoot" Owl
Scientific Name: Strix varia

Size: 16-25 inches (40-63 cm); Wingspan: 38-49 inches (96-125 cm)

Habitat: North America; widespread in North America, they occur across most of the eastern half of the continent from Florida northward to southern Canada; they are also spreading westward in the north of their range. Northern populations may be partially migratory depending on food resources.

Barred Owls live year-round in mixed forests of large trees, often near water. They tend to occur in large, unfragmented blocks of mature forest, possibly because old woodlands support a higher diversity of prey and are more likely to have large cavities suitable for nesting. Their preferred habitats range from swamps to streamsides to uplands, and may contain hemlock, maple, oak, hickory, beech, aspen, white spruce, quaking aspen, balsam poplar, Douglas-fir, lodgepole pine, or western larch.

Status: Least Concern. Global population: 3,000,000 adult individuals with an increasing population trend. Barred Owls are fairly numerous and their populations increased 1.7 percent per year between 1966 and 2010, according to the North American Breeding Bird Survey. Until the twentieth century, Barred Owls were residents of old, undisturbed forests in eastern North America. They were probably restricted from moving into northwestern boreal forests because of frequent forest fires. But fire suppression—along with tree planting in the Great Plains—allowed them to spread northward and westward during the past century. They eventually expanded south along the West Coast as far as northern California, where they began competing with Spotted Owls. Barred Owls have displaced these slightly smaller and less aggressive owls and started hybridizing with them, further threatening the already compromised Spotted Owl population. Barred Owls are forest birds. They tend to occur in older forests and they need large, dead trees for nest sites; these requirements make them sensitive to expansion of logging. For this reason, the Barred Owl is often used as an indicator species for managing old forests.

Diet: A very opportunistic hunter; meadow voles are its main prey, followed by shrews and deer mice. Other mammals include rats, squirrels, young rabbits, bats, moles, opossums, mink, and weasels. Birds are taken occasionally, including woodpeckers, grouse, quail, jays, blackbirds, and pigeons. They also eats small fish, turtles, frogs, snakes, lizards, crayfish, scorpions, beetles, crickets, and grasshoppers.

A nocturnal bird, hiding in dense foliage during the day, usually high up. It may also roost on a branch close to a broad tree-trunk, or in a natural tree hole. It may become very aggressive when defending a nest. It will use a perch, from where it dives upon its prey. Birds are taken as they settle into nocturnal roosts, because they cannot catch birds on the wing. They will also swoop down to the water's edge to catch frogs, other amphibians, and occasionally fish. Barred Owls are attracted to campfires and lights where they forage for large insects. Prey is usually devoured on the spot. Larger prey is carried to a feeding perch and torn apart before eating.

Nesting: Males and females are alike. The facial disc is pale grayish-brown with darker concentric lines. The rim is not very prominent. Eyes are dark brown to blackish-brown. The cere is pale horn and the bill is orange to pale yellow with sometimes a slight greenish tint. The sides of the head and neck are barred light and dark. The upper parts are brown to grayish-brown, scalloped with whitish bars on the crown, back and mantle. Wing-coverts are spotted whitish. Flight feathers are barred whitish-buff and brown. The tail is brown or grayish-brown with 4-5 whitish bars. Underparts are pale grayish-brown to dirty whitish. The upper breast and fore neck are densely barred light and dark. The rest of the underparts are boldly streaked dark to rufous-brown. The tarsi are feathered, and toes are almost totally feathered, the bare parts being yellowish-gray. The claws are dark horn with blackish tips.

Barred Owls call year-round but courtship activities begin in February with breeding occurring between March and August. Males hoot and females give contact calls. As the nesting season approaches, males chase after females giving a variety of hooting and screeching calls. Males display by swaying back and forth, and raising their wings, while sidling along a branch. Courtship feeding and mutual preening also occur. Barred Owls nest in cavities and will also use abandoned Red-shouldered Hawk, Cooper's Hawk, Squirrel, or Crow nests. Eggs number 2-4 and are white, and almost perfectly round, with a slightly rough texture. They are likely laid every 2 to 3 days and incubation begins with the first egg laid. Incubation period is 28-33 days. The Male brings food to the female while she is on the nest. The Barred Owl is single-brooded but has a long breeding season, which allows for laying of replacement clutches if the first clutch or brood is lost. When the young leave the nest, at about 4 weeks, they are not able to fly, but crawl out of the nest using their beak and talons to sit on branches. They fledge at 35 to 40 days. Once they lose their down, there is no difference between adult and juvenile plumage.

Parents care for the young for at least 4 months, much longer than most other Owls. Young tend to disperse very short distances, usually less than 10km, before settling. Pairs mate for life and territories and nest sites are maintained for many years.

Cool Facts: Barred owls may be partly responsible for the recent decline of the northern spotted owl, native to British Columbia, Washington, Oregon, and California. Since the 1960s, barred owls have been expanding their range westward from the eastern US, perhaps because man-made changes have created new suitable habitat in the west. When spotted owls and barred owls share the same environment, the latter are generally more aggressive and out-compete the former, leading to decreased populations of the native owls. They have also been known to interbreed, with the hybrids named "sparred owl" or "botted owl", which are sterile, and further threaten the population stability of the Spotted Owl.

The Great Horned Owl is the most serious predatory threat to the Barred Owl. Although the two species often live in the same areas, a Barred Owl will move to another part of its territory when a Great Horned Owl is nearby.


Found in Songbird ReMix Owls of the World Volume 2

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