Western Screech-Owl

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Common Name: Western Screech-owl
Scientific Name: Megascops kennicottii

Size: Males 8 ¼ inches (22 cm); Wingspan: 21 inches (54 cm)

Habitat: North America. This owl is resident from south-coastal and extreme southeastern Alaska, coastal (excluding Queen Charlotte Islands) and southern British Columbia, northern Idaho, western Montana, northwestern Wyoming, Colorado, extreme western Oklahoma, and western Texas south to Baja California.

Western Screech Owls also occurs northern Sinaloa and across the Mexican highlands through Chihuahua and Coahuila as far as the Distrito Federal. They are essentially non-migratory.

Western Screech Owls inhabit a wide variety of habitats. On the northwest coast, they are found in humid Douglas-fir, western hemlock, western red cedar, and Sitka spruce forests along the edges of clearings, rivers, and lakes. Further inland they occupy a narrow ecological niche of lowland deciduous forests, especially riparian woodlands along river bottoms. Southern populations inhabit lowland riparian forests, oak-filled arroyos, desert saguaro and cardon cacti stands, Joshua tree and mesquite groves, and open pine and pinyon-juniper forests. They avoid dense forests because Great Horned Owls use that habitat, and high elevation forests. In general, they require open forests, with an abundance of small mammals and insect prey, and cavities for nesting. They roost mainly in natural or woodpecker cavities in large trees, but also in dense foliage of deciduous trees, usually on a branch next to the trunk, or in dense conifers.

Status: Least Concern. Global population: 700,000. Western Screech Owls are dependent on deciduous woodlands or open mixed forests that have suitable nesting sites and sufficient prey densities. Removal of riparian forest in drier regions will cause population declines because most densities are highest in riparian zones. However, this adaptable Owl can survive in wooded suburban areas and city parks. The removal of dead and dying trees will eliminate this bird as a breeding species from local areas.

Diet: Favorite foods include small rodents such as shrews, kangaroo rats, deer and pocket mice), larger insects (including beetles, larval moths & butterflies), or small birds depending on abundance.

Screech Owls are nocturnal, with activity generally beginning 20-30 minutes after sunset. Hunts mainly from a perch in open woodlands, along the edges of open fields or wetlands, or makes short forays into open fields. They also capture flying insects on the wing. Small prey is usually swallowed whole on the spot, while larger prey is carried in the bill to a perch and then torn apart.

Nesting: Females are slightly larger. During courtship males and females call to each other in a duet as they approach. When together they preen each other's heads and nibble at the other's beaks. The male then changes his call to a rapid tremolo, answered with a short, tremolo from the female.

Western Screech Owls nest almost exclusively in tree cavities. Enlarged natural cavities are preferred but they will also use old Pileated Woodpecker and rotted-out Northern Flicker holes. Nest cavities are usually 6 ½ to 20 feet above the ground. They will readily nest in suitable nest boxes. Nests are almost always in deciduous trees such as oaks, cottonwoods, maples, sycamores and large willows, but also in large cacti, Douglas-fir snags, and junipers. One subspecies in Arizona nests exclusively in saguaro cacti. No nest material is added and nests are kept cleaner than in Eastern Screech Owls. 2 to 5 eggs are laid on natural sawdust on the floor of the cavity. The average clutch size tends to increase from south to north and from the coast inland. The eggs are laid every 1 to 2 days and incubation begins after laying of the first. The incubation period is about 26 days and the fledging period about 35 days. Females incubate eggs and brood young while males bring food to the nest. The Western Screech Owl is single brooded, but may re-nest if first clutch is lost. Pairs will often reuse nest sites in consecutive years. Pairs mate for life but will accept a new mate if the previous mate is lost. Gray and red color phases will mate together.

Adults tend to remain near their breeding areas year-round while juveniles disperse in the autumn. Small territories around nest sites are vigorously defended by males. In desert riparian areas of the southwest, where these Owls can be quite numerous, territories may be only 50 meters (165 feet) apart. Home ranges are much larger, and range from 3 to 60 hectares (7.5 to 150 acres), but these are not defended and there is much overlap between pairs.

Cool Facts: The western Screech Owl was first discovered in 1867. The species name "kennicotti" was created to honor Robert Kennicott, an American explorer and naturalist (1835-1866) and was originally called "Kennicott's Owl".

There is much individual variation within the two color morphs. In the gray-phase, birds in the dry southwest are a paler gray, while birds in the humid northwest are darker and browner. The red-phase is very rare and found only in the Pacific Northwest.

Adult (gray phase) - Facial disks are dusky white with fine gray-brown mottling. Overall gray-brown, with gray-brown narrow vertical stripes, bars, and spots on the underparts, and barred wings and tail. The legs have fine buff mottling.

Adult (red phase) - Similar pattern to gray phase except dull cinnamon instead of gray. The face is buff light cinnamon. There is rufous spotting on the breast with black anchor marks.

This owl is very aggressive when defending a nest site, and may attack humans.


Found in Songbird ReMix Owls of the World Volume 1

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