Fall 1999 Table of Contents

Who's That?

Screech, Saw-whet Owl nest box

Barn Owl nest box

1. Securely knot one end of a 5" long piece of nylon rope. Thread it through a small hole made in the top of one side so that the knot is inside the box. Then thread the rope through a small hole at the other side and knot the rope inside. The box can be hung inside a barn or other building about 20" above the ground. If placed in a tree, first wrap the rope around a sturdy limb before threading through the second hole. 2. Place box on a cross-beam with the front facing the inside of the building. Nail the box through the bottom to the cross-beam. 3. To permit direct access to the box from the outside, place the box against the inside of a wall after cutting a 6"x6" entrance in the barn wall at the level of the entry on the box. Materials: 1-4x8x5/8" exterior plywood, 1-1x12x6' rough cedar board, 2 galvanized hinges with galvanized screws, 5' of nylon mounting rope (optional), 35-1 5/8" outdoor wood screwsor 35 #7 galvanized nails, two coats of dark latex exterior paint (if mounted outside).

"Who, Who, Who’s That," you ask? Well if it sounds anything like that, it could be one of 13 species of owls native to Washington.

Some are uncommon or unlikely in your backyard due to habitat preferences, like the Great gray owl of the mountains, Burrowing owl of shrub-steppe areas, or endangered Spotted owl of old-growth forests.

The following are most likely to be seen or heard around your home.

The Great horned owl (Bubo virginianus) is unmistakable for its large ear tufts or "horns." It’s also called the "cat owl," probably because those tufts look like cat ears, but maybe because it’s known to prey on house cats not kept in the house! This two-foot owl with a four-foot wingspan makes meals of small to medium-size mammals. Its hooting is heard more often than this nocturnal hunter is seen, but its large-headed, necklace silhouette, even at dusk, is hard to miss.

Year-round residents here, GHOs begin courtship in January, hooting at each other from atop large trees. By March they use old hawk or heron nests to lay two to three eggs for a month’s incubation. Young take three months to fledge and are fairly dependent on parents through the summer (when you may hear their begging cry for food.)

Like all owls, GHOs have feather layers so tight and dense that their flight is noiseless, advantageous to swooping in on prey. All owls have large eyes in flattened faces or facial "disks" to better hear and see prey, too; the GHO’s ear tufts may be useful extensions of that design.

If you have an owl roosting spot on your property, you may find "pellets" of indigestible bones, fur, and feathers that GHOs and other owls regurgitate from their prey.

The Western screech owl (Otus kennicottii) is much smaller at about ten-inches in length but also with small ear tufts. It is usually dark brown and has a unique series of whistles that "screech" through the night. A year-round resident, it nests in tree cavities, like old woodpecker holes, but will also use nestboxes (see design.) Screech owls favor areas near water and prey mostly on rodents, birds, and large insects.

The Northern saw-whet owl (Aegolius acadicus) is smaller still, about the size of a blackbird, with dark brown plumage but no ear tufts. This seemingly tame or simply fearless little owl does migrate and may appear in some areas of Washington only in the winter. "Saw-whet" comes from its most common voice, an almost mechanical repetitive whistle that sounds like saw filing. Like the screech owl, it nests in tree cavities but will use a nestbox (see design). It prefers conifer forests and mostly hunts small mammals.

The Northern pygmy owl (Glaucidium gnoma) is our smallest owl at just seven inches long, including its long tail carried at a tilt. Because of its size, un-owl-like shape (besides tail, head is proportionately smaller), shrike-like flight and day-time hunting, the pygmy owl is often misidentified or overlooked as "just another brown bird in the brush." Watch for it near your winter feeder where this fearless hunter will take on bigger birds or mammals. It has sharply streaked undersides, but most telling are the black patches on the back of its head that mimic "eyes" and may help intimidate prey. It can sometimes be attracted by imitating its staccato tooting.

The Barn owl (Tyto alba) is unique with its white heart-shaped face, dark eyes, golden-buff plumage with ghostly light underparts, and long legs that give it up to 20 inches in height. Despite its sinister appearance, and rasping scream that sounds like ripping canvas, this owl may be one of our best feathered friends as a living mousetrap. Although it nests in open country natural cavities, it earned its name by ready use of barn rafters and other structures (including boxes – see design.) The Barn owl tends to be a year-round resident in milder parts of Washington, but may migrate out of harsher areas by fall. By March it lines its nest with fur pellets, lays 5-10 eggs,and in three weeks hatches young that fledge within two months (by mid-May).

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