Introduction
Screech owls, native to the Americas, encompass over twenty-one species, all generally under 10 inches tall. These diminutive birds of prey have carved out a niche for themselves in various ecosystems, showcasing remarkable adaptability in their diet and hunting strategies. This article delves into the intricate details of screech owl feeding habits, exploring what they eat, how they hunt, and how their diet varies across seasons and species. It also touches upon ways to attract these fascinating creatures to your backyard while emphasizing their importance in local ecosystems.
General Description and Habitat
Eastern screech owls are small, compact, nocturnal owls with ear tufts and lemon-yellow eyes. There are 2 common color morphs; gray and rufous, or “red.” Gray morphs are the predominate morph in Pennsylvania and are more cold-hearty than their southern, reddish cousins. Red and gray morphs will mate together, producing brownish-gray offspring. Screech owls camouflage effectively against tree bark and are readily found in suburban areas throughout the Eastern United States. There is a slight difference in size, with females being the larger of the two sexes, a pattern called “reversed sexual dimorphism.” Eastern screech owls thrive best in patches of mixed forest landscapes, similar to what is found in most of suburban Eastern North America. They avoid continuous tracts of forest, and areas of high elevation. Factors that likely dictate the presence of screech owls include a low density of predators, a nearby waterway, ample nest cavities, evergreens for roosting, and optimal hunting grounds. Suburbia often provides these requirements.
Dietary Diversity
Screech owls are carnivorous birds of prey with a highly varied diet. Their feeding is opportunistic; they consume a wide array of prey depending on availability and geographic location. Documented prey items include mice, voles, insects, crayfish, earthworms, spiders, amphibians, reptiles, small fish, small birds, snails, the occasional bat, and even other screech owls! Screech owls are opportunistic feeders and take advantage of seasonal abundance in prey.
Prey Size and Limitations
Screech owls' small size naturally restricts them to hunting prey that they can effectively grasp with their talons and swallow whole. This excludes larger animals from their diet, as they can only carry prey within a specific size and weight range.
Regional Variations
The diet of screech owls varies with latitude; screech owls further North have a limited variety of available prey compared to their southern counterparts. For example, rodents form a large part of the diet of an Eastern screech owl, while a Western screech owl’s diet contains more reptiles and crustaceans.
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What Birds Do Screech Owls Eat?
Due to their own small stature, screech owls eat smaller birds, such as blue jays, chickadees, thrushes, creepers and woodpeckers. Many of the bird species frequently hunted by screech owls are songbirds.
Hunting Strategies
Screech owls are skilled hunters, employing different strategies to capture their prey.
Sit-and-Wait Predation
Eastern screech owls are sit-and-wait predators. They remain on a perch until they identify prey (animals they eat) using their keen sense of sight or heightened sense of hearing.
Silent Flight
Owls have softened edges on their feathers, giving them near silent flight.
Hunting Techniques
Feeding behavior consists of watching, waiting, and snatching prey. Occasionally screech owls will hover before seizing their meal. They hunt mostly at night, but like other owls, are active at dusk and dawn. Screech owls hunt from perches around 1.8 to 3 m (6 to 10 ft) off the ground, using their acute hearing to sense potential prey before swooping down. Their sharp talons and strong, curved beaks help them to catch, kill, and carry their prey, and tear it into smaller pieces if needed. Because they are so small, if prey cannot be swallowed whole screech owls carry it back to their nest to avoid losing it to an even larger predator.
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Sensory Adaptations
The owls are alerted to the presence of prey by their highly accurate sense of hearing and wait on a relatively high up perch before swooping in to catch whatever they have detected. Like other owls, they have exceptional hearing and great night vision, which helps make them excellent hunters.
Temporal Aspects of Feeding
Screech owls exhibit specific feeding patterns related to the time of day and year.
Nocturnal Behavior
Screech owls are nocturnal, meaning they hunt and feed at night and sleep during daylight hours.
Seasonal Diet Variations
Screech owls take advantage of seasonal abundance in prey. For example, they may switch between consuming fish or insects during the summer, to primarily vertebrates during the winter. These habits vary with latitude. In winter months, screech owls will continue to eat whatever prey is available, particularly insects and small rodents. Insects, such as moths, beetles and grasshoppers, as well as earthworms, snails, and in wetland areas, crayfish and minnows, form a significant part of their winter diet. In summer months, a screech owl’s usual diet is supplemented by any young animals that it might encounter, including baby rabbits, shrews, voles, moles, and pocket gophers.
Feeding the Young
The diet of baby screech owls differs from that of adults, especially in their early stages of development.
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Diet of Owlets
The initial diet of baby screech owls consists of soft, easy-to-digest food that is regurgitated by their parents. Larger prey items are introduced before they fledge, and once they leave the nest, they continue to be fed and supported by both parents until they gradually master the art of independent hunting by the time they reach 8 to 10 weeks. Initial catches, however, are restricted to insects and earthworms.
Digestive Process
Birds can digest whole prey. Birds do not have teeth and are not able to chew food. Because of this, they have a specialized part of their stomach, called a gizzard, that helps with digestion by grinding food. The small stones, sand, and grit that birds pick up while they are eating are stored in the gizzard. Once food is swallowed and makes its way to the gizzard, it is pulverized by the grit and stomach muscles. Some birds like chickens, ducks, and turkeys have thick, muscular gizzards. Individual screech owls expel roughly two pellets per day, containing bones fragments and other indigestible parts of their prey.
Attracting Screech Owls
Many backyards offer a natural source of mice, rats, earthworms, and frogs - which is already an excellent start to attracting screech owls. Many backyards are already the ideal habitats for Screech Owls. Screech-Owls readily accept nest boxes; consider putting one up to attract a breeding pair. Make sure you put it up well before breeding season. Attach a guard to keep predators from raiding eggs and young. Find out more about nest boxes on our Attract Birds pages. You'll find plans for building a nest box of the appropriate size on our All About Birdhouses site.
Conservation Status and Human Impact
Eastern screech owls are listed as a Species of Least Concern under the IUCN’s Red List. Screech owls are declining, yet their population is large enough that they are not yet considered a global conservation priority. Screech owls are compatible with suburban environments. However, they still require essential habitat features such as nest cavities, safety from predators, a reduction in vehicle collisions (a leading cause in screech owl mortality) and appreciation from humans. You can support your local screech owl population by driving slowly at night, refraining from rodenticide use, leaving trees with cavities standing when possible, installing screech owl nest boxes, and acknowledging the role these owls play in your neighborhood rodent and insect populations. Most importantly, you can spread the word about how amazing these charismatic screech owls truly are, and support Hawk Mountain in our work to help support owl populations worldwide.