Great Horned Owl

Bubo virginianus

By Andy McCormick

  • Length           22 in
  • Wingspan      44 in 
  • Weight           3.1 lb (1400 g)
  • AOU Band code    GHOW

 Now is the time of year to keep your ears perked up for the hoo-hoo-HOO-hooo-hoo Good for you, me too call of the Great Horned Owl, probably the most widespread owl in North America which can be found in a variety of wooded sites. Its hooting is the quintessential sound of an owl at night, but it also makes other vocalizations such as clucks, screams, and squawks.These owls breed in winter and as part of courtship they will call in a duet at dawn or dusk. The hooting of the female is generally higher pitched than that of the male. After chicks hatch the adults remain mostly quiet.

The Great Horned Owl is a fierce predator. Its diet is made up of a variety of mammals including those as large as a hare and birds including hawks. It will also consume rodents and snakes. The Great Horned attacks with extremely powerful talons which first crush its prey. Then its hooked bill is so powerful it will sever the spinal column of even prey that outweigh the owl.

It is an early nester. The first eggs can hatch as early as January (Alderfer). The male initiates courtship with hooting and display flights as early as October and November (Houston, et al). Typically the Great Horned does not build its own nest, choosing instead to use the old nests of a Red-tailed Hawk, crow, heron, or other large bird species, but it will also nest in a broken tree stump or cave or on a cliff ledge (Kaufman). It adds little nesting material except pehaps a few feathers. A Great Horned Owl can reuse a nest and males have a high degree of filiopatry, fidelity to their nest site.

Usually two to three dull whitish eggs are deposited and the female incubates them for about a month. After hatching the owlets are dependent on the parents for food for several months even continuing to beg for food until the following fall (Houston, et al). However, they will begin to leave the nest to climb on nearby branches at around five weeks of age. At this stage the young owls are sometimes called “branchlings.” They can begin flights at around 9-10 weeks of age (Kaufman).

The Great Horned is a long-lived bird with some individuals reaching age 20 or more. It is highly adaptable to changing habitat conditions and can be found in almost any habitat in North America except the arctic, high altitudes and extreme desert (Houston, et al). It is named after the two tufts of feathers that resemble horns. Its genus Bubo is from the Greek buas, horned or buzo, to hoot.

Although the population of Great Horned Owls is thought to be robust, more research is needed to obtain more accurate information about them (Houston, et al). Their numbers are generally not counted in breeding bird surveys, which are held in April and May and count birds by ear, when these owls have usually stopped hooting. At this time there are no conservation measures required for the Great Horned Owl, a denizen of our woodlands which adds a spirit of wilderness when encountered.  

Photo by Mick Thompson

Photo by Mick Thompson

Barred Owl

Strix varia

By Hugh Jennings

  • Length           21 in
  • Wingspan      42 in 
  • Weight           1.6 lb (720 g)
  • AOU Band code    BARR

The Barred Owl (BARR, due to conflict with Barn Owl being BAOW) is about 21” long with a wingspan of 42” and a weight of 1.6 lb. (720 g). This compares with 17.5”, 40” WS and 1.3 lb. for its cousin, the Spotted Owl. The genus name Strix (STRIKS) comes from the Greek, strizo, meaning to screech. The species name varia (VAY-rih-ah) is from Latin and means “variegated in plumage”.
The Barred Owl is stocky, round-headed, broad-winged and short-tailed. The Barred, Spotted and Barn Owls are our only owls with dark eyes. The Barred Owl has no ear tufts and has dark barring on the upper breast and dark streaking below.
It favors mostly dense and thick woods with only scattered clearings, especially in low-lying and swampy areas. It is common in deciduous and mixed woods in the southeast, but in the north and northwest may be found in coniferous trees. The Barred Owl is found throughout eastern U.S., across southern Canada and has recently expanded from British Columbia into Washington, Oregon and northern California. It first was noted in Pend Oreille County in 1965 and has since spread throughout the state. Its range expansion threatens the Spotted Owl with which it sometimes hybridizes. Its distinctive call is a rhythmic series of loud hoots: who-cooks-for-you, who-cooks-for-you-all. The call is sometimes preceded by a ascending agitated barking.
The owl eats mice, rabbits, reptiles, insects and amphibians. It hunts most at dawn or dusk and seeks prey by watching from a perch or flying through the forest.
Courtship includes both male and female bobbing and bowing heads, raising wings and calling while perched together. The male and female often call in duet.
Their nest is in a large natural hollow in a tree, broken-off snag, or on an old nest of a hawk, crow or squirrel. Two to three white eggs, rarely 4, are laid. Incubation is mostly by the female and lasts 28-33 days. The male brings food to the incubating female. The female may stay with the young much of the time at first, while the male hunts and brings food back for her and the young. First flight is in about six weeks.
Barred Owls are permanent residents throughout its range. However, individuals may wander away from nesting habitat in the winter.

Photo by Mick Thompson

Photo by Mick Thompson

Spotted Owl

Strix occidentalis

By Andy McCormick

  • Length          17.5 in
  • Wingspan      40 in 
  • Weight           1.3 lb
  • AOU Band code    SPOW

“The Northern Spotted Owl is an indicator species for Pacific Northwest old-growth forest; in other words, the state of this bird represents the state of these forests. In this role, it has become an icon of efforts to preserve old-growth forests in the region” (Bannick). The Northern Spotted Owl lives in the northwestern maritime forest which has a mix of western red cedar, western hemlock, Douglas fir and Pacific silver fir located west of the Cascade Crest.

The Northern Spotted Owl of the Pacific Northwest is one of three subspecies along with the California Spotted Owl and Mexican Spotted Owl. The genus Strix is originally from the Greek strix, an owl. Occidentalis is Latin referring to the west or western, this owl’s natural range. The common name Spotted refers to the white spots on it plumage (Holloway). The Northern subspecies is darker than the other two and it has smaller spots. Many bird species have darker plumage in the northern, wetter climates. 

Spotted Owls are brown overall with elliptical white spots on most of its body. They do not have ear tufts as some other owls do. Their flight is low and direct (Alderfer). The call is a low four-note hoot which can be heard at the Macaulay Library. They are strictly nocturnal but can sometimes be found roosting in a tree during the day.
Spotted Owls begin nesting in March choosing a cavity in a large hollow tree or possibly in a cave. They do not build a nest, but make a scrape of debris at the site. Usually two eggs are deposited. The female will incubate the eggs for about a month. During this time the male will bring food for the female and then continue to feed the young, which are ready to leave the nest after five weeks. The adults will continue to tend them for several more weeks feeding on voles, deer mice, woodrats and other smaller owls and birds (Kaufman).

The habitat requirements for Northern Spotted Owls are quite specific and because this habitat has a high commercial value as harvested wood by the logging industry, this owl has been studied more than any other species as part of a long-running controversy pitting those who want to preserve its habitat and those who want to log the forests. Nest sites are found more frequently in deeper forest areas in late stages of maturity. “In general, this species uses forests with greater complexity and structure than random sites for nesting in both managed and unmanaged forests” (Guttierrez, et al). The Northern subspecies is now listed as endangered in Washington and Canada and threatened under the US Endangered Species Act.

Further adding to its already steep decline has been expansion of the range of the Barred Owl, an Eastern North American species that has been nesting in Washington and California. The Barred Owl is aggressive toward Spotted Owls and, despite the success states have had in preserving old-growth habitat, the population of Northern Spotted Owls continues a steep decline. “Between 2000 and 2007, the population of Northern Spotted Owls in Washington State fell by approximately 50 percent” (Bannick). There may be 300 nesting pairs existing in its range.  To counter this trend the US Fish & Wildlife Service has adopted a plan to experimentally kill Barred Owls in four geographical areas to allow Spotted Owls time to recover in the absence of Barred Owls. One of the four areas is near Cle Elum, WA. UFWS officials believe if humans do not interview the Northern Spotted Owl is on a road to extinction. 

Photo by USFWS

Photo by USFWS

Barn Owl

Tyto alba

By Andy McCormick

  • Length           16 in
  • Wingspan      42 in 
  • Weight           1 lb (460 oz)
  • AOU Band code    BNOW