Order Strigiformes – Owls
Family Strigidae – true owls
Scientific Name: Otus asio
Description: This owl resembles a miniature great horned owl with ornamental feathery tufts on the top of the head. Size ranges from 7 – 10 in. The females are slightly larger than males. Color ranges from reddish-brown to a pale gray independent of age, sex, or season. Like all true owls, the eyes are directed forward and the facial disk is prominent. The head is large in relation to the body and the neck is not noticeable. Screech owls have several different calls. The territorial call of the Eastern screech owl is a series of descending trills (a “whinny”) heard most frequently just after dark, late fall to early spring. The male courtship call is a series of 30-70 rapid monotonous notes uttered at a constant speed and the alarm call is a sharp “keerr.”
Home Range: Southern central and eastern Canada to Florida and northeastern Mexico.
Habitat Type: Deciduous forests and forest edges, open woodlands, orchards, cultivated land, suburban parks and gardens, creek bottoms and riparian areas in grasslands.
Reproductive Habits: Males use a courtship call to attract females in early spring. The female will then find a nest 5 – 30 feet off of the ground. They will frequently use small birds’ nests (after devouring the previous occupant), abandoned crow’s nests, or natural hollows in trees. The female lays a clutch of 4 - 5 glossy white eggs usually from mid-March through mid-May. Although the male does not help to incubate the eggs, he will bring the female food each night and frequently store small mammals inside of the nest. The young will hatch in 26 days and are blind (rare among predatory birds). Juveniles will not leave the nest for at least a month and are sexually mature at one year.
Diet in Wild: Screech owls are very opportunistic feeders and will eat nearly any available animal that is small enough to catch and kill, including insects, arthropods, small mammals, birds, amphibians, bats and worms.
Diet in Zoo: 1/2 oz. Bird of Prey meat, 1 small mouse Wednesday, fast on Sunday.
General Info: There appears to be much debate and disagreement over whether there is one type of screech owl or several. Many authorities recognize the Western screech owl and the Eastern screech owl while others lump the two together into one species known as the common screech owl (we do not know which type of screech owl we have at our zoo). Still others claim that there are as many as nine distinct subspecies of this bird. Regardless of the classification, all screech owls have the same basic appearance and the differences seem to lie only in varying territorial calls and distribution.
Screech owls prefer more open woodland. The thinning of the Eastern Deciduous Forest has benefited this species and allowed it to spread west. Unfortunately, this expansion has come at the expense of other owls such as the barred owl and the great horned owl.
The screech owl’s color phases have intrigued ornithologists for over 100 years. Color is independent of sex or age. Some studies indicate that temperature and available vegetation selects one phase over another. The reddish brown phase appears most commonly in the Southeastern US where temperatures are warmer and the trees and leaves available for roosting tend to have a reddish cast. The paler gray phase has better camouflage in the northern parts of their range where tree bark tends to be gray. After very harsh winters, scientists have noted a decrease in the number of red phase screech owls. This particular owl is very well adapted to life near humans. It is strictly nocturnal and rarely seen in the daytime. Screech owls are very protective of their young and will dive and strike at humans who wander near the nest. However, an adult screech owl will often play “possum” when handled.
Predators: Larger owls and raptors.
Conservation Status: Listed on CITES appendix ll.
Audubon Society Field Guide to North American Birds—Western Region. 1977. Miklos D. F. Udvardy. Alfred A. Knopf. New York. p. 621.
Birds in Kansas. Vol I. 1989. Max C. Thompson et al. University of Kansas Press. Lawrence, KS. pp. 329-330.
Grzimek’s Animal Life Encyclopedia. Vol 8 Birds II. 1975. Bernhard Grzimek. Van Nostrand Reinhold Company. New York. pp. 392-397.
Grzimek’s Animal Life Encylopedia. Vol. 9, Birds II. 2003. Bernhard Grzimek. p. 355.
Owls of the Northern Hemisphere. 1988. Karel H. Voous. The MIT Press. Cambridge, MA. pp. 64-68.