asio (Linnaeus, 1758) includes previously described races no longer considered valid such as M. Much of the variation may be considered clinal, as predictably, the size tends to decrease from north to south and much of the color variation is explainable by adaptation to habitat. Subspecies įive subspecies are typically treated for the eastern screech owl, but the taxonomy in the species is considered "muddled". Through much of the eastern United States, eastern screech owls are essentially physically unmistakable, because other owls with ear tufts are much larger and differently colored and the only other small owl, the northern saw-whet owl ( Aegolius acadius) is even smaller, with no ear tufts, a more defined facial disc, and browner overall color. Other somewhat similar species that may abut the eastern screech owl's range in its western and southernmost distribution, like the Middle American screech owl ( Megascops guatemalae formerly called "vermiculated screech owl"), whiskered screech owl ( Megascops trichopsis), and the flammulated owl ( Psiloscops flammeolus), are distinguished by their increasingly smaller body and foot size, different streaking pattern on breast (bolder on the whiskered, weaker on the others), different bare part coloration, and distinctive voices. The eastern and western screech owls overlap in the range in the Rio Grande valley at the Texas– Mexico border and the riparian woods of the Cimarron tributary of the Arkansas River on the edge of southern Great Plains. The only reliable distinguishing feature is the bill color, which is considerably darker (often a black-gray) in the western and olive-yellow in the eastern their voices also differ. Besides coloration, the western screech owl is of almost exactly the same general appearance and size as the eastern. In the closely related western screech owl ( Megascops kennicottii), no color morphs are known all owls of the western species are gray. A paler gray variation (sometimes bordering on a washed-out, whitish look) also exists in western Canada and the north-central United States. In Florida, brown morphs are typically reported in the more humid portions of the state, whereas they appear to be generally absent in the northern and northwestern parts of the state. Florida), which may be the occasional product of hybridation between the morphs. A rarer "brown morph" is known, recorded exclusively in the south (i.e. The highest percentage of red morphs is known from Tennessee (79% of population) and Illinois (78% of population). While the gray morph provides remarkably effective camouflage amongst the bark of hardwood trees, red morphs may find security in certain pine trees and the colorful leaves of changing deciduous trees. Rusty birds are more common in the southern parts of the range pairings of the two color variants do occur. Two color variations are referred to as " red or rufous morphs" and "gray morphs" by bird watchers and ornithologists. Eastern screech owl (gray morph) in Canada The eastern screech owl (and its western counterpart) are actually some of the heaviest screech owls, the largest tropical screech owls do not exceed them in average or maximal weight, but (due to the eastern screech owls' relatively short tails) they are surpassed in length by Balsas ( M. The feet are relatively large and powerful compared to more southern screech owls and are typically feathered down to the toes, although the southernmost populations only have remnant bristles rather than full feathering on the legs and feet. They have a large, round head with prominent ear tufts, yellow eyes, and a yellowish beak, which measures on average 1.45 cm ( 9⁄ 16 in) in length. Midsized by screech-owl standards, these birds are stocky, short-tailed (tail averages from 6.6 to 8.6 cm ( 2 + 5⁄ 8 to 3 + 3⁄ 8 in) in length) and broad-winged ( wing chord averages from 14.5 to 17 cm ( 5 + 3⁄ 4 to 6 + 3⁄ 4 in) in length) as is typical of the genus. They have either rusty or dark gray intricately patterned plumage with streaking on the underparts. In Ohio, male owls average 166 g ( 5 + 7⁄ 8 oz) and females 194 g ( 6 + 7⁄ 8 oz) while in central Texas, they average 157 g ( 5 + 1⁄ 2 oz) and 185 g ( 6 + 1⁄ 2 oz), respectively. The wingspan can range from 46 to 61 cm (18 to 24 in). Among the differently sized races, length can average from 19.5 to 23.8 cm ( 7 + 11⁄ 16 to 9 + 3⁄ 8 in). Description Illustration of the eastern screech owl by AudubonĪdults range from 16 to 25 cm ( 6 + 1⁄ 2 to 10 in) in length and weigh 121–244 g ( 4 + 1⁄ 4– 8 + 5⁄ 8 oz). This species is native to most wooded environments of its distribution, and more so than any other owl in its range, has adapted well to manmade development, although it frequently avoids detection due to its strictly nocturnal habits. The eastern screech owl ( Megascops asio) or eastern screech-owl, is a small owl that is relatively common in Eastern North America, from Mexico to Canada.
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