Corkscrew SIGHTINGS: Screech-owls are masters of camouflage



Eastern screech-owl perched in a hole in a tree.

Eastern screech-owl perched in a hole in a tree.

As night falls across Audubon’s Corkscrew Swamp Sanctuary, imagine that a mysterious trill pierces the silence followed by another in response. Along the boardwalk, visitors who are participating in a special guided night walk sense they are being watched.

Suddenly, out of an old-growth bald cypress cavity, a small bird drops on quiet wings, streaking through patchy moonlight, and snatches a small mouse scurrying along the boardwalk railing. Poof! The raptor and its prey are gone, back into the darkness of the cavity.

Eastern screech-owls are pint-size raptors that are common and wide-ranging in the eastern United States. These owls live in forests, parks, and even suburbs. During the day, they hole up in tree cavities, dense vegetation, or other hiding spots before becoming active at dusk. Many people will unknowingly pass by these masters of camouflage. But at night, you can hear their trills and soft whinnies. Despite their name, they don’t screech.

These raptors feed on myriad small animals ranging from birds and mammals to lizards, frogs, insects, and even earthworms. Screech-owls are agile and occasionally dine on bats. During times of abundance with plentiful prey, they will cache extra food in tree holes. The food can stay in these caches for up to four days.

Because they prey on small songbirds, you can sometimes find Eastern screech-owls during the day if you encounter songbirds making a commotion. This behavior alerts others to the predator’s presence, teaches younger birds to be wary of these owls, and just might be annoying enough to cause the owl to seek refuge elsewhere.

Screech-owls regurgitate indigestible parts of their prey in the form of pellets. Owl pellets are usually oval and are composed of bones, fur and feathers. It is possible to find owl pellets littering the ground at the base of frequently used owl roosts, and researchers have used owl pellets to study owl diets.

Eastern screech-owls cannot create cavities for themselves, so they rely on tree holes that have been naturally created by woodpeckers, fungus, rot or squirrels. Their eggs incubate for 27-34 days, and once hatched, mother owl and the nestlings will be fed by her mate, who defends a small territory rife with multiple cavity roosts. The young continue to rely on the parents for food as they slowly learn the ropes and become independent about eight to 10 weeks after fledging.

Audubon’s Corkscrew Swamp Sanctuary and its 2.25-mile-long boardwalk are open daily from 8 a.m. to 3 p.m. with last admission at 1 p.m. Learn more at corkscrew.audubon.org.