All owls have specially designed eyes, ears, and wings
to enable them to capture their prey.
eyes are large and on the front of their faces, giving them binocular vision and
fine depth perception. They have a large concentration of rods on their
retinas, but they see little color. Their eyes are ten times as
light-sensitive as human eyes, but they are short-sighted so they hunt near the
ground. Their eyes are so large that there is little room in their skulls
for eye muscles. Thus an owl turns its head, sometimes as much as 270
degrees, rather than its eyes, to follow a moving object.
Owl ears are located on the
sides of the "facial disks," those round feather arrangements, and give owls the
most highly developed sense of hearing of all birds. The facial feathers help to
amplify and channel sounds to their ears. Generally one ear is larger than the
other and slightly above or below, so the owl can pinpoint the location of a
sound. It can hear a mouse or a cricket in the grass below!
The owl's feathers are
silent in flight. The wings have downy fringes along the stiff flight feathers
which muffle sound as the owl approaches its prey.
Owls swallow their prey
whole. Then later they cough up a "pellet" of bones and fur. Owls can often be
found in the woods by locating these pellets on the ground, or by finding their
white droppings, called "whitewash."
None of the species of owl
in North America is a nest builder. The Eastern and Western Screech Owls,
among others, nest in cavities and take readily to a birdhouse.
The Eastern Screech Owl
(Otus asio) lives generally in wooded areas east of the Rockies, while
its Western cousin (Otis kennicottii) lives to the west of them. They
look a lot alike, with small, thick bodies and large "ear" tufts, which are not
actually ears at all (the ears are located on each side of the head, beside the
eyes). Most are a gray-brown color with whitish spots and stripes
throughout. They have sharp, hooked beaks and powerful feet. The adult
owls are only 8 to 9 inches tall.
The name might indicate
that the sound they make is a screech, but it comes closer to singing. It
is a favorite sound of many bird lovers on warm spring nights.
Screech owls breed from
March, in the South, into July further north, and inhabit a small area close to
the site of their nest. They have one brood a year of four to six young,
and they are not generally migratory, preferring to be year-round
Screech owls are typical
"night owls," hunting at night and sleeping during the day. They have a
varied diet of small rodents and night-flying insects. They may even be
seen catching moths under city street lights.
Because they also
occasionally eat other small birds that may be roosting in the trees at night,
you may want to place the owl house away from the houses for your other
The Saw-whet Owl
(Aegolius acadicus) is named for its call, which sounds like filing or
"whetting" a saw. It also gives a series of short, monotonous whistles
during breeding season. It is a small owl, only about 7" tall, without
"ear tufts," and with large yellow eyes. It is brown, streaked with white
above, with a reddish-brown facial disk and streaks of white and reddish-brown
on the underside.
The Saw-whet Owl generally
lives in low, moist, coniferous or mixed wooded areas, in evergreen thickets,
wooded swamps, or even in isolated pine trees. It likes the densest parts
of trees where it can roost safely without being seen from above by predatory
hawks and owls. It is almost entirely nocturnal, roosting during the day
in or near their nesting hole, or in dense foliage during the winter.
Saw-whets are very tame,
and very sound sleepers, when roosting. They are difficult to find, but
may be approached and even held.
At night they prey on
insects, mice and other small rodents. They may occasionally eat a small
bird as well.
Saw-whet owls are found
nesting across the northern and western states and southern Canada. They
winter primarily through the middle West and the lower South.
The Barred Owl (Strix
varia) can be recognized by a pattern of "bars," or stripes, running across
its chest horizontally and down its belly vertically. In contrast to many
other owls with yellow eyes, this owl has dark brown eyes.
This owl is the most
commonly heard at night, with a typical "hoot" associated with owls. It
sounds a bit like "Who cooks for you?"
The Barred Owl is about 20"
long with a 44" wing span. It has no ear tufts. It lives in low, wet
woods and swampy forests, but it also likes residential areas with lots of
trees. It feeds at night on rodents, birds, frogs and crayfish and rests
during the day. It is one of the few owls which will take to a nesting box
and requires no nesting materials. It generally does not migrate, but
resides year-round east of the Rockies.
The young Barred Owl can
climb trees, even as nestlings and young fledglings. Sometimes they leave
the nest before they can fly, so they are able to get back safely.
The Barn Owl (Tyto
alba) is one of only five species of owl which take to birdhouses
readily. It makes some of the most unusual of all bird sounds. It
may resemble the screech of metal scraping against metal or the rush of steam
coming out of an engine.
Its large white,
heart-shaped face makes the Barn Owl easily recognized: the male and
female look alike. It is a large bird, 18" high with a wing span of
44". It is buff-brown above and white below.
The Barn Owl eats meadow
voles and other rodents almost exclusively. It does most of its hunting
for food at night. The Barn Owl's breeding period is March into
July. Its territory is only the area around the nest site. The nest
may be lined with leaves, grasses and other debris.
The Barn Owl is found in
all but the northernmost states and migrates slightly south from northern