Western Screech Owl
(Megascops kennicoti)
Classification
and Range
Western screech owls are part of the family
Strigidae or “typical” owls. They are one
of the smaller owls found within this family with ear
tufts and well-developed facial discs. There are approximately
36 species in the genus Megascops and, in North America,
three species of screech owls; eastern (M. asio), western
(M. kennicoti) and whiskered (M. trichopsis). In total,
there are 18 recognized subspecies of western screech
owls. Western screech owls inhabit open woodlands, wooded
stream and river banks throughout Pacific Coast mountain
ranges in Canada and from the Pacific Coast to the Rocky
Mountains in North America.
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Habitat
Due to their wide distribution, western screech owls use a variety of habitats.
Habitat can vary from tropical coast lowlands to desert habitats in the
south, to temperate rain forests in the North. In general, these owls prefer
partially open country with many deciduous trees around, particularly oaks,
sycamores and riparian hardwoods.
Physical
Characteristics
Western screech owls
are small owls measuring from 6.5 to 8 inches (16-20 cm)
in length with a wingspan of 20 to 22 inches (52-56 cm).
Their body is gray to brownish-gray in color with a streaked
chest and belly. They have black bills and yellow eyes. They
have prominent ear tufts when they are raised. Like many
other raptor species, females and males are similar in color.
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Range Map |
Western screech owls are nocturnal.
Their vocalizations consist of a series of short whistles that increase
in tempo near the end. They sometimes will use a double trill tone
when alarmed..
Life
Span
In both
the wild and captivity, screech owls can live to about 13 years.
Diet
In the wild: The western screech owls hunt small mammals, insects, snakes,
lizards, frogs, small birds and even crayfish and scorpions. In winter,
when prey is scarce, screech owls have even been seen attacking larger
birds such as domestic ducks and pheasants. In summer, these birds
can often be seen hunting insects and moths around street lamps.
At
the zoo: Mice, insects and coturnix quail.
Reproduction
It
is believed that female and male western screech owls mate for life. They
vocalize heavily at the beginning of the breeding season and will engage
in mutual head-preening when a potential mate is found. The breeding season
is short, typically lasting from March to May. Nest sites in the western
screech owl vary greatly according to habitat. Favorite nest choices include
natural tree hollows and cavities excavated by woodpeckers. They lay two
to seven eggs that are incubated mainly by the female for 30 days.
Life
Cycle
Young chicks are ready to leave the nest at 30-32 days of age
and the success rate of reaching fledging age is quite high, around 73%
of eggs hatched in the nest. Being hit by automobiles is a large mortality
factor in the first year of life in western screech owls.
Screech
or no Screech?
The western screech owl has two distinct calls, neither of which
are a screech. The first call is often described as a bouncing ball. It
is a series of even and distinct notes, which start slowly then accelerate
and runs together, like a ball that bounces more quickly as the bounce
gets smaller. The second call, used when a male and female are dueting,
is a short trill followed quickly by a longer one.
Location
at the Zoo
A western screech owl is housed at the Raptor Center at the zoo. He is missing
a wing and is only visible to the public when being handled or when used in
education programs. Great horned, spectacled and barred owls can be seen at
the raptor center along with the bald eagle, gyrfalcon and turkey vulture.
A spotted owl or great gray owl can be found in the Temperate Forest adjacent
to Bug World, snowy owls are on display in the Northern Trail exhibit and a
barn owl can be located at the Family Farm.
Conservation
Connection
In many areas, screech owls have suffered substantial habitat losses. On the
other hand, relatively abundant food supply and probable increased protection
from great horned owls has allowed screech owls to become more abundant in city
parks and suburban areas.
Many
raptor species are in trouble. Human-caused changes in land use are
escalating, and this affects the habitats and migratory corridors
required by some raptors
for survival. Vast forests are being removed for timber and other paper products,
and industrial emissions are polluting water and air resources. Critical shoreline
and riparian zone habitats are being rapidly converted by expanding human communities
and agricultural needs. Shooting and trapping are also lowering raptor numbers.
It's only a matter of time until more raptor species may face extinction, unless
we take measures to protect their habitats.
Humans
need raptors. Here are only a few of the benefits raptors
provide:
- Raptors
help keep animal populations in balance.
- Raptors
consume many animals that humans consider as pests, including mice,
rats and destructive species of insects. This helps to control disease
and damage to crops.
- As
top predators of their food chain, raptors are an indicator species
of the overall health of the ecosystem in which they live.
- Of
equal importance, witnessing wild raptors enriches each of our lives.
Imagine what life would be like if we could no longer hear the haunting
evening call of the owl.
How
You Can Help!
Efforts to save threatened and endangered raptors require cooperation and support
at international, national, regional and individual levels. You can help in
this cause. Join and become active in Woodland Park Zoo and other conservation
organizations of your choice. Recycle forest products. Eliminate or reduce
pesticide use. Support breeding programs for endangered birds of prey at zoos
and other animal care organizations. Let your elected representatives know
your views about the conservation of migratory birds and their wild habitats.
Contact
Woodland Park Zoo at webkeeper@zoo.org to
find ways you can support conservation programs at the zoo or visit
our How
You Can Help section. Discover more about raptors by contacting
the Peregrine Fund at their Web site www.peregrinefund.org.
Sources
and Suggested Reading
Burton, J.A. (editor). 1992 (third ed.). Owls of the World: Their
Evolution,
Structure and Ecology. E.P. Dutton, New York, NY. 216 p.
For Kids!
Jarvis, Kila and Denver W. Holt. 1996. Owls: Whoo Are They? Mountain
Press Publishing Company, Missoula, MT. 59 p.Zoobooks. 1992. Owls. Wildlife
Education, Ltd., San Diego, CA. 17 p.
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