People have asked me about owls appearing in the houses of wood ducks. Eastern screech-owls are the ones that will roost and nest in wood duck and other larger wooden nest boxes, such as a flicker house.
Owls are often seen sunning themselves at a nesting box entrance during the winter. A male and a female may roost together, and are thought to mate for life. Normally they nest and roost in tree cavities. Old woodpecker cavities come to mind.
In March or April, four to five white eggs are laid, but no nesting material is used. The female incubates the eggs for about 25 days, and the male feeds his mate during that time.
Eastern screech-owls stand about 9 inches, have yellow eyes, and have plumage that changes to gray or red-brown. They are the only small owl species in Minnesota with ear tufts, and are year-round residents of the southern half of the state. A wide variety of habitats suit them: woodlots, forests, swamps, orchards, parks, and even suburban gardens.
A fairly common owl, active at dusk and during the night, the eastern screech has excellent hearing and eyesight. They feed on small mammals and birds. They also eat large insects in summer. Screech-owls seldom give a screeching call but more often a steady trill.
Jim Gilbert’s Nature Notes are heard on WCCO Radio at 7:15 a.m. Sundays. His observations have been part of the Minnesota Weatherguide Environment Calendars since 1977, and he is the author of five books on nature in Minnesota. He taught and worked as a naturalist for 50 years.