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.Back to top
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.Back to top
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.
|Clutch Size:||2-7 eggs|
|Egg Length:||1.3-1.6 in (3.2-4.2 cm)|
|Egg Width:||1.1-1.4 in (2.7-3.6 cm)|
|Incubation Period:||26-34 days|
|Condition at Hatching:||Covered in white down; eyes closed.|
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. 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.Back to top
Western Screech-Owl population trends are difficult to study because of their nocturnal habits but populations appear to have declined slightly between 1966 and 2019, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 180,000 and rates them 13 out of 20 on the Continental Concern Score, indicating a species of relatively low conservation concern. The Pacific Northwest population of Western Screech-Owls has proven vulnerable to predation from recently arrived Barred Owls. High-density development, clearcutting of forests, and their dependence on standing dead trees for nest sites have also had a negative impact on screech-owl numbers. In addition, Western Screech-Owls thrive near streamside vegetation which tends to be prime real estate for humans. Maintaining robust populations of the Western Screech-Owl will require protecting open forested areas along bodies of water in both rural and residential areas. However, the Western Screech-Owl can adapt to human presence and will use nest boxes, which will help with conservation efforts.Back to top
Cannings, R. J., T. Angell, P. Pyle, and M. A. Patten (2020). Western Screech-Owl (Megascops kennicottii), version 1.0. In Birds of the World (P. G. Rodewald, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.