Western Screech Owl - Megascops kennicottii
Formerly Otus kennicottii
Calls - Megascops kennicottii
The western Screech Owl was first described in 1867. The species name
"kennicotti" was created to honour Robert Kennicott, an American explorer and
naturalist (1835-1866). Originally, this bird was officially called "Kennicott's
Owl". Common names include Little Horned Owl, Dusk Owl, Ghost Owl, Mouse Owl, Cat
Owl, Little Cat Owl, Puget Sound Screech Owl, Washington Screech Owl, and Coastal Screech
[For help with terms used in the description, see parts of an owl. For general characteristics common to most owl species, see owl physiology.]
Description: The Western Screech Owl is a small, nocturnal,
woodland Owl of western North America and is one of the west's more common Owls at lower
elevations. They are squat-looking Owls that sit erect, with their plumage fluffed out,
with the feet and legs obscured, and distinct ear tufts raised. The iris is bright yellow
and the bill is gray to black, with tufts of bristly feathers around its base. The facial
disk is bordered by black. The toes are yellow. Plumage is either mainly grayish or
reddish-brown variegated dark and light, resembling a furrowed tree bark pattern. They use
the variegated plumage as camouflage. When threatened, the bird stretches its body and
tightens its feathers in order to look like a branch stub to avoid detection, but will
take flight when it knows it has been detected. They have noticeable light spotting along
the edge of the scapulars. There is much individual variation within the two colour
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 rare and found more in the
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
The juvenile of both colour phases is similar to the adults, but the indistinct stripes
and bars are more patterned, with many feathers tipped with white.
The Western Screech Owl is likely to be confused with the Eastern Screech Owl and Whiskered Screech Owl. These Owls
can be distinguished by bill colour (Eastern Screech Owls have gray-green bills while
Western Screech Owls have gray to black bills) and their different calls. Western and
Eastern Screech Owls only occur together locally in eastern Colorado and southern Texas.
Western and Whiskered Screech Owls only occur together in southern Arizona and Mexico.
Size: Length 22-24cm. Wing length 142-190mm. Weight 90-250g. Females are larger than males.
Habits: Nocturnal, with activity generally begining 20-30 minutes after sunset. Flight is noisless with soft wingbeats and gliding. Will become motionless if disturbed at roost, and can sometimes be cought by hand in this state. This owl is very aggressive when defending a nest site, and may attack humans. During direct flight, the Western Screech Owl flies fairly rapidly with a
steady wing beat of about 5 strokes/second. It rarely glides or hovers, but may fly
bat-like with erratic movements, when manoeuvring through wooded areas. Wings are broad
and the head is held tucked in giving a flying bird a stubby appearance.
Voice: The male's most common call is a mellow, muted trill
bouncing ball song, that
speeds up at the end, but maintains a constant pitch. It is given by the male during the
mating and nesting seasons, but also during the autumn and winter. This call is primarily
territorial in nature. A secondary song is a double trill of rapid bursts. Other calls are
a soft "cr-r-oo-oo-oo-oo" given as a greeting call, and a sharp bark given when
Hunting & Food: 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.
An extremely wide range of prey species is captured. The most favoured prey are small
microtine rodents and deer mice, larger insects, or small birds depending on abundance.
Prey species include shrews, orthopterons, insects (including beetles, larval moths &
butterflies), birds, pocket gophers, voles, salamanders, kangaroo rats, wood rats, pocket
mice, bats, grasshopper mice, gophers, frogs, locusts, and scorpions, crayfish, worms,
snails, small fish, poultry, and barnyard ducks.
Pellets are medium-sized, averaging about 3.8 by 1.9 centimetres (1.5 by 0.75 inches).
They are compact, dark gray, ovals composed of fur, feathers, bones, teeth, and chitin.
Two to four pellets are cast each day.
Breeding: During courtship males and females call to each other
in a duet as they approach each other. 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 2 to 6 metres (6.5 to 20 feet) above the
ground, but may be up to 15 metres (50 feet) up. 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 (average 3-4) 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 colour 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
Mortality: Western Screech Owls can fall prey to Northern
Goshawks, Cooper's Hawks, Great Horned Owls, Barred Owls, Spotted Owls, Long-eared Owls,
Great gray Owls, Short-eared Owls, mink, weasels, raccoons, skunks, squirrels, snakes, and
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 as
long as long as they are not directly persecuted. Populations likely fluctuate more
depending on prey availability. Nest box programs can enhance local populations,
especially in areas short of suitable tree cavities. Silviculture practices that include
removal of dead and dying trees can eliminate this bird as a breeding species from local
Habitat: Western Screech Owls inhabit a wide variety of habitats. On the
northwest coast, they inhabits 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.
Distribution: 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.
Distribution of the Western Screech Owl Megascops kennicottii
Status: Locally frequent to common.
Original Description: Elliot, Daniel Giraud. 1867. Proceedings of the Academy of Natural Science of Philadelphia, 19, p. 99-100.
M. k. aikeni,
M. k. bendirei,
M. k. macfarlanei,
M. k. suttoni,
M. k. vinaceus,
M. k. xantusi,
M. k. yumanensis,
M. k. cardonensis
Campbell, Wayne. 1994. "Know Your Owls (CD-ROM)". Axia Wildlife
Page compiled by Deane P. Lewis. Page last updated 2012-08-13
OwlPages.com Owl Species ID: 040.010.000