The western screech owl (Megascops kennicottii) is a small owl native to North and Central America, closely related to the eastern screech owl. The scientific name commemorates the American naturalist Robert Kennicott. Western Screech-Owls are small owls with stocky bodies. They have somewhat square heads, almost no neck, and conspicuous ear tufts. The tail is short. They are superbly camouflaged birds with a base color that can be grayish, brownish, or reddish-brown (rufous). The upperparts are flecked with white; the breast and belly are pale with dark, spidery streaks. The face is pale, outlined with dark arcs. The eyes are yellow.

Western Screech-Owls live mainly in forested habitats, especially in bands of deciduous trees along canyons and other drainages. Common trees include cottonwood, aspen, alder, water birch, oak, and bigleaf maple. But you can also find Western Screech-Owls in suburbs, parks, deserts, coastal areas, and in mountains up to about 6,000 feet elevation.

Western Screech-Owls are nocturnal. They usually leave their roosts around sunset to forage, returning within a half-hour of sunrise. You may glimpse them perching at the entrances of their roost cavities on sunny winter days. They are “socially monogamous,” meaning that pairs raise young together, although both sexes may also mate outside the pair. The male and female in a pair often preen each other. During courtship and mating, they sing duets, and the male presents food to the female. Like many small owls, Western Screech-Owls nest in tree cavities excavated by woodpeckers. They may also use naturally occurring cavities, such as those formed where branches have broken off a trunk. Very occasionally, they nest in cavities in cliffs and banks. They sometimes use nest boxes. Wherever the location, the male owl finds a suitable hole, then calls or leads the female to it, sometimes by carrying an enticing prey item. They may use the same cavity for several years in a row. The Western Screech-Owl does not build a nest, but lays its eggs on whatever material happens to be in the cavity. Western Screech-Owl nest cavities are about 1 foot in diameter and 1 to 1.5 feet deep. Entrances are just big enough to admit an owl’s body; presumably this helps prevent larger predators from getting in. Western Screech-Owls sometimes take over the nests of other species. In breeding season, the male roosts near the nest cavity. During the last weeks of the nestling period, the female also leaves the nest, often roosting close enough to the male that their bodies touch. Both adults guard the entrance from crows, jays, and other predators. The male provides almost all the food for the female and young during nesting, while the female incubates eggs and broods the baby owls. She stays with her young constantly for the first 3 weeks, then takes increasingly long breaks to help the male hunt. Owlets leave the nest before they can fly well. They remain with their parents for about 5 weeks after leaving the nest site.

Western Screech-Owls are carnivores. They eat mostly small mammals, thought they also eat birds, fish, amphibians, and invertebrates. Their diet can vary tremendously from place to place and from season to season. Mammal prey includes pocket mice, deermice, grasshopper mice, shrews, woodrats, kangaroo rats, as well as bats and occasionally rabbits. Invertebrate prey include insects, crayfish, worms, slugs, snails, and whip scorpions. They are sit-and-wait predators, perching inconspicuously on tree branches and watching the ground for prey. These owls sometimes perch above creeks, watching for crayfish to emerge from the shallows. They also glean invertebrates from foliage and catch flying insects in midair, or bats leaving a roost. Due to their small size, they are also predated by larger animals such as hawks, skunks, snakes, or larger owls.

Heard at dusk and into the night, the Western Screech-Owl’s most distinctive vocalization is its “bouncing ball” song: a series of 5–9 short, whistled hoots, speeding up ping-pong-ball fashion toward the end. The male uses this for territorial and courtship advertising, often calling from a nest tree or a prospective nest site. In duets sung by a mating pair, the female’s notes are interspersed with the male’s—her voice higher than her mate’s, despite her larger size. To stay in contact, pairs of screech-owls use a short “double trill” call; when agitated, they make a barking sound. Adult females whinny in response to the male’s bouncing ball song, and to solicit feeding and copulation. Western Screech-Owls snap their bills when approached closely by a potential predator such as a crow, squirrel, or human. Nestlings begin doing this when they are about 8 days old. Here is a link so you can listen to this bird too.