If a mysterious trill catches your attention in the night, bear in mind the spooky sound may come from an owl no bigger than a pint glass. Common east of the Rockies in woods, suburbs, and parks, the Eastern Screech-Owl is found wherever trees are, and they’re even willing to nest in backyard nest boxes. These supremely camouflaged birds hide out in nooks and tree crannies through the day, so train your ears and listen for them at night. [ facts source: Cornell University – All About Birds ]
One of the more exciting new additions at Peace River Wildlife Center is our white screech owl. This little guy is not an albino, but is leucistic. An albino has a lack of melanin, the pigment that appears as black/brown color; although the cells that produce it, melanocytes, are still present. Some albino animals (snakes, fish, turtles, etc.) are pale yellow or orange because they have different pigments being produced other than black and brown. Leucistic individuals lack the cells that make all pigment throughout their bodies, because they are all derived from a single source in embryonic development, and hence have no color at all. An albino’s eyes will appear pink or red due to the lack of pigment in the iris. The blood vessels behind the eye are usually masked by the colored iris, but their reddish hue is seen behind the (clear) iris in an albino. A leucistic animal will usually have normally colored eyes because the pigment cells in the iris are derived from a different progenitor cell, directly within the eye.
When the white screech owl nestling originally presented to us, we tried to find his nest in order to return him to it. We went back out to the Charlotte Harbour Environmental Center where he was found on the ground behind the visitor’s center. There was no evidence of a screech owl’s nest anywhere in the vicinity that we could see. It is entirely possible that the parents and maybe even the siblings of this bird intentionally kicked him out of the nest to prevent him from drawing attention to the young family. Being such a tiny bird of prey, the screech owl’s main advantage is its camouflage. Their bark-colored feathers allow them to blend into the tree in which they are perching. As he grew and started to perch on the edge of the nest, he was a beckoning white flag waving to nearby predators, We surrender! Come eat us! This little marshmallow would quickly become the component of some predator’s s’more if left on his own. Since this little guy’s chances of long term survival in the wild are slim, he will become an education ambassador at PRWC. Our education ambassadors are permanent resident animals that go to classrooms, festivals, and other venues to give people a hint at what we do here at PRWC.
Be sure to stop by the Screech Owl Habitat and see “Luna” on your next visit.
Adopt Luna Today!
Like most raptors, male Eastern Screech-Owls are smaller than females, and are more agile fliers and hunters. The female doesn’t hunt while on the nest; she and the chicks depend on food brought them by the male. Though the male is smaller, his voice is deeper than the females. Smaller birds can help you find screech-owls during the day. Listen for a commotion of Blue Jays, chickadees, and titmice they may be mobbing a screech-owl (or other raptor), swooping around it with noisy calls. This can be enough of a nuisance to make the owl move on, and it alerts other birds to the predator’s presence and teaches younger members of the flock about the danger. Screech-owls regurgitate the bones, fur, and feathers of their prey in an oval pellet, usually once or twice a day. The ground beneath habitual owl roosts can be littered with pellets, and you can learn a lot from them about the owls diet. However, data from pellets may underestimate the number of soft-bodied animals, like worms and insects, the owl has eaten. Nestling Screech-owls fight fiercely among themselves for food, and sometimes even kill and eat their smallest sibling. Eastern Screech-Owls of the suburbs may fledge more young than their rural counterparts, probably because their predators are scarcer in the suburbs. Red and gray individuals occur across the range of the Eastern Screech-Owl, with about one-third of all individuals being red. Rufous owls are more common in the East, with fewer than 15% red at the western edge of the range. No red owls are known from southern Texas, although they occur further north in Texas and further south in Mexico. Intermediate brownish individuals also occur in most populations. Eastern Screech-Owl pairs usually are monogamous and remain together for life. Some males, however, will mate with two different females. The second female may evict the first female, lay her own eggs in the nest, and incubate both clutches. The Eastern Screech-Owl is known to eat a variety of songbirds, including the European Starling. Despite this fact, the starling regularly displaces the owl from nesting sites and takes over the hole to raise its own brood.
Almost any habitat with sufficient tree cover will do for this cosmopolitan owl. Tree cavities or nest boxes are essential, and fairly open understories are preferred, but Eastern Screech-Owls live and breed successfully in farmland, suburban landscapes, and city parks. On the Great Plains, at the westernmost edge of its range, Eastern Screech-Owls occur in the uneven traces of wooded land along streams and rivers. Screech-owls cannot survive if all trees are removed, but the species readily recolonizes once trees are replanted, especially if nest boxes are also provided.
Eastern Screech-Owls eat most kinds of small animals, including birds and mammals as well as surprisingly large numbers of invertebrates, including earthworms, insects, crayfish, tadpoles, frogs, and lizards. They eat many kinds of mammals, including rats, mice, squirrels, moles, and rabbits. Small birds taken as prey include flycatchers, swallows, thrushes, waxwings, and finches, as well as larger species such as jays, grouse, doves, shorebirds, and woodpeckers. This owl is agile enough to occasionally prey on bats, and can rarely even be cannibalistic. When prey is plentiful, Eastern Screech-Owls cache extra food in tree holes for as long as four days.
Eastern Screech-Owls build no nest. The female lays her eggs on whatever debris is at the bottom of her nesting cavity, be it wood-chips, twigs, or the cast-off feathers and droppings from a previous years nest. Settling in, she makes a body-shaped depression where her eggs lie.
Eastern Screech-Owls nest in holes and cavities, but never dig a cavity themselves. Thus, they depend on tree holes opened or enlarged by woodpeckers, fungus, rot, or squirrels. They often occupy abandoned woodpecker nest holes. Eastern Screech-Owls readily accept nest boxes, including those built for Wood Ducks or Purple Martins, and sometimes nest in wood piles, mailboxes, or crates left on the ground.
Eastern Screech-Owls are chiefly active at night, though they often hunt at dawn or dusk, and occasionally in daylight. These versatile hunters sit and wait in the trees for prey to pass below. They tend to pounce from perches six to ten feet off the ground, occasionally snatching an insect or bat on the wing or hitting shallow water talons-first to snag fish or tadpoles. Most flights are short (less than 75 feet or so). When traveling between perches, these owls often drop, fly straight, then rise again, in a characteristic U-shaped pattern. Eastern Screech-Owls form stable matches, usually one male with one female but occasionally one male with two females. Males defend small territories containing several cavity roost spots. When nesting, the female stays in the nest hole except for brief dawn and dusk excursions. She and the nestlings are fed by her mate, though it is the female who tears the prey into small bits for the babies. At fledging, the young first hop to the ground or nearby branches, using feet and fluttering wings to climb laboriously back to safety. Young gain flight and hunting skills slowly; they depend on their parents for food for 8-10 weeks after fledging. Both parents feed the youngsters at this stage, and adults, especially the females, shelter together with the young in communal tree roosts. Gradually, as the young gain skill, they begin to roost and hunt apart from their parents and siblings.
The Eastern Screech Owl is in no current conservation danger. This little owl is a generalist, with unfussy eating and nesting habits, and it adjusts well to the presence of humans. In fact, suburban birds often survive better than their rural kin, as suburbs provide more prey, milder climates, and fewer predators. Eastern Screech-Owls need trees to nest in, or, at least, nest boxes and brushy cover, but their small size, territorial tolerance, and broadly varied diet make this owl a successful survivor.
[ facts source: Cornell University – All About Birds ]