EASTERN SCREECH OWL (Otus asio)
RANGE: Southern part of Canada down to north-eastern Mexico, all of the United States east of the Mississippi River except northern Maine, and as far west as eastern Montana, Wyoming, and Colorado.
HABITAT: Open woods and suburbs with large shade trees.
SIZE: Length: 7-10 inches Wingspan: 18-24 inches Weight: 4-6 ounces (about the weight of a quarter-pounder with cheese)
LIFE EXPECTANCY: WILD: 3-8 years CAPTIVITY: Up to 12 years
REPRODUCTION: In this area the breeding season is March and April, which is relatively short. The clutch size is 3 - 5 eggs, and the incubation period is approximately 26 days. Chicks fledge at 30 - 32 days. Nests are usually found in natural cavities (like Woodpecker holes) in trees, but they will use man-made nest boxes.
DIET: WILD: Small mammals (mice, rats, moles, voles, shrews, flying squirrels, chipmunks, and bats); small birds (songbirds, rock doves, bobwhites, ruffed grouse, kestrels, and other screech owls); reptiles and insects (snakes, lizards, frogs, toads, salamanders, small fish, snails, crayfish, spiders, scorpions, millipedes, earthworms, moths, and grasshoppers). CAPTIVITY: Mice and crickets.
BEHAVIOR: EASOs form pair bonds that are monogamous and lifelong. Bonding behavior includes calling in synchronized duets, mutual preening, and rubbing of facial area. Defend only a small territory that includes the nest site and a peripheral area surrounding the nest site.
POINTS OF INTEREST: EASOs are the smallest tufted owl in the United States, but six other owls in the US are smaller.
There are two color phases: red and gray. The differences are arbitrary (like our hair color) and have no relationship to age, sex, etc.
EASOs can be differentiated from Western Screech Owls by the color of their bills. The Eastern Screech Owl’s bill is grayish green and the Western's is black. Also, the Western Screech does not show the red color phase.
EASOs are called the "feathered wildcat" because of their ferocity when defending their nests and because of their audacity at taking some prey. There have been cases recorded where EASOs flew down a chimney, went directly to a canary cage, pulled out the canary, and swallowed it whole.
Predators: Being small birds, EASOs are often preyed upon by larger owls, particularly the Great Horned. Cats are also major predators of the owl, particularly young birds and birds that have made a kill too large to be carried to a safe perch. They were also the most commonly hit raptor in a study done on Ohio highways, and the second most commonly hit bird overall (the robin was the most commonly hit). This is a result of the tendency of the bird to hunt in open areas adjacent to woods, and this type of habitat is common along roads.
Camouflage: An EASO attempting to hide from predators would perch on a branch next to a tree and pull its feathers close to its body while erecting its ear tufts, effectively blending into the trunk and appearing to be no more than another bump on the tree.
Vocalizations: Main call sounds like mournful, descending whinny, much like a horse's neigh. The name "Screech Owl" is a misnomer, since the owl makes an actual "screech" only when extremely upset (i.e. a wild owl being handled, etc.).
Plumicorns: The Plumicorns (ear tufts) are only feathers and have nothing to do with hearing. Their function is to show expression, like our eyebrows. The ear tufts allow them to look larger and more threatening when showing aggression. They also serve to lengthen the owl when it sits against the trunk of a tree so that it blends in and resembles a bulge on the tree.
STATUS: Screech Owl populations have fluctuated since the 1940's with no clear directional trend evident. Perhaps the screech owl's utilization of suburban areas has balanced out the habitat loss in woodlands and creek bottoms.
IN ADDITION: This information is generally included in the EASO portion of the program, but it applies to all owls. Owls have 14 vertebrae in their neck and we have 7. In fact, all mammals with the exception of 2 have 7, including the giraffe. An owl can turn its head 270 degrees (3/4 of the way around) in either direction. This adaptation is necessary because the birds have such large eyes there is no room in their skull for muscles to move those eyes. So, owls must turn their heads to look directly at an object before they can see it.