BIRD OF THE WEEK: November 16, 2018
SCIENTIFIC NAME: Megascops asio
HABITAT: Open forests east of the Rockies
The little Eastern Screech-Owl lives alongside people in many suburban and even urban settings throughout the eastern United States. Although widespread, this nocturnal bird, like the Barn Owl and Eastern Whip-poor-will, often goes unseen and is best detected by its vocalizations. (Scroll down to hear its voice.)
During nesting, the male brings food while the female broods the eggs and young; like the male Northern Saw-whet Owl, it often caches several days' worth of food for the nestlings. The Eastern Screech-Owl's varied diet includes small birds and mammals, reptiles, insects, crayfish, and earthworms.
This eclectic diet sometimes includes worm-like reptiles called blind snakes, which the adult owl brings to the nest alive. The owl chicks eat some of them, but other blind snakes escape being a meal by burrowing beneath the wood chips, pellets, and other debris on the nest cavity's floor. The surviving blind snakes dine on insect larvae that would otherwise parasitize the owl nestlings. A recent study showed that screech-owl chicks grew faster and healthier in nests kept vermin-free by "helper" blind snakes.
Like other owls, Eastern Screech-Owls regurgitate pellets that contain indigestible fur and bones; finding these pellets beneath a tree may be one clue to an owl's presence.
Eastern Screech-Owls are permanent residents in a wide variety of habitats, particularly wooded suburban neighborhoods and parks, riparian areas, orchards, and woodlands near marshes, meadows, and fields. They tend to avoid dense forests, habitats frequently inhabited by Great Horned Owls, which readily prey upon the smaller screech-owls.
Five subspecies of Eastern Screech-Owl are recognized, varying in color, size, and voice. This owl occurs in rufous and gray morphs, and, rarely, in a brownish plumage. Birds of different color phases often mate together. Male and female plumages are alike, but as in many other birds of prey, including the Flammulated Owl and Cooper's Hawk, the female is larger.
The Eastern Screech-Owl's vocalizations include a distinctive, whinny-like call and a low-pitched trill, given during nesting season to maintain pair and family bonds, to attract mates, and during aggressive interactions between individuals. Both males and females vocalize, although males tend to be more noisy.
If you've heard these odd sounds, you may have an Eastern Screech-Owl as a neighbor!
(Audio: Call recorded in Edgartown, Mass. by Tim Spahr, XC286959. Accessible at www.xeno-canto.org/286959. Song recorded in Atsion, NJ by Don Jones, XC1160. Accessible at www.xeno-canto.org/1160.)
Eastern Screech-Owls nest in tree cavities, either naturally formed or old woodpecker holes. They will also use nest boxes and may even nest behind loose boards on abandoned buildings or barns. Pairs often reuse nest sites in consecutive years.
Like the Short-eared Owl, the Eastern Screech-Owl has an elaborate courtship ritual. A courting male approaches a female while calling, then bobs and swivels his head and entire body, even slowly winking his eyes as part of this performance. If the female accepts him, the pair will touch bills and preen each other. These owls mate for life, although they will seek a new mate if one disappears.
Together, we can change the story for birds. Help us get results.
Although the Eastern Screech-Owl is still considered a common species, Partners in Flight data show a decline in populations in some areas. This owl is often the victim of collisions with glass and vehicles. Screech-owls that nest in suburbs and orchards are vulnerable to pesticides, and like so many other birds, they are affected by habitat loss.
ABC's Bird-Smart Glass program offers a number of solutions to protect these little owls. Our Bird-Friendly Life web page also suggests ways to protect birds and bird habitats. If you have a wooded yard, you might even consider building a screech-owl nest box.
By December 31, 2018, ABC wants to raise $1 million for bird conservation. Please consider donating to this effort, and we can write a better story for the Eastern Screech-Owl and other birds!