A couple of weeks ago we explored the world of birds with different color traits known as “morphs.” One of the birds with distinct color variances that got a passing mention was the eastern screech-owl. These darling little owls are elusive and fascinating creatures that merit a closer look.
Downstate readers and folks who’ve lived further to the south may be more familiar with this robin-sized raptor than South Shore residents. Most range maps show the northern end of their territories as ending around Green Bay and then extending further north into the Great Plains and southern Manitoba. But the map from eBird shows a number of reported sightings around the Chequamegon Bay area over the past five years (especially around the Bibon Swamp) and a couple of range maps I found show the Bay Area as part of their intermittent, or “scarce,” range.
Eastern screech-owls are non-migratory and live in their home range year-round, but like a lot of birds they wander during the winter months in search of food. So this might be the best time of year to encounter one. In Wisconsin, they’re a lot more common south of the I-90 and Highway 10 corridors.
As we’ve discussed, eastern screech-owls come in a rusty red or “rufous” morph, and a gray morph. Both variants have mottling and dark vertical streaks in the plumage. They’re “eared” owls that are about the size of a robin, and their head makes up nearly half of their bodies. That mottled plumage serves them well during the daytime when they blend in so completely with tree bark that trying to find one in a photograph is like trying to see the image in one of those Magic Eye puzzles. We’re not likely to see this very nocturnal owl in the daytime even when they aren’t camouflaged, unless they’re being mobbed by a flock of songbirds.
Eastern screech-owls are cavity dwellers. They roost and nest in tree cavities, including those excavated by other species such as pileated woodpeckers, and they will readily move into a nesting box put up by humans. A quick Google Images search shows plenty of examples of screech-owls hanging out in mailboxes and other repurposed abodes. They raise their broods in these cavities, but they don’t bother with building a nest; the mom just incubates the eggs right on the floor of her house. Eastern screech-owls take a while to reach independence and will depend on their parents for food and protection for up to 10 weeks after they fledge. Those parents generally mate for life, although males will occasionally mate with two females, one of which may evict the other and then lay her own eggs alongside her predecessor’s. She then incubates all those eggs, which hardly sounds like a bargain to me.
Eastern screech-owls are highly adaptable, agile birds who eat all manner of critters including a number of birds that are comparable or even larger in size. They also eat a large number of earthworms, fish and, occasionally, bats. Which is just bonkers. They tend to raise bigger broods in suburbs, parks and smaller cities thanks to these areas having fewer predators.
People living in cities with areas of greenbelt (screech-owls can’t live in areas without trees) may be familiar with their loud, eerie song. This song sounds more like a whinny than a screech, but they do have a defensive call that probably gave them their name. They also have an equally eerie trilling song. I remember hearing them back in the creek bed from my childhood bedroom in Indiana. Their sound was unsettling in the middle of the night, but it was hard to be creeped out in the daylight when I looked the little squirts up in my field guide.
Eastern screech-owl populations are slowly declining across parts of their range, but they appear to be generally stable and doing well in areas where nesting boxes are common. If you live or have property in areas where they’re more common, you can put up nesting boxes that are designed for them (kestrels also like these boxes), but generally they aren’t particular and will nest in wood duck boxes, purple martin houses or an old crate. Keep an ear out on a quiet night and you might be lucky enough to hear their lonesome call.
Morris, a bird-watcher and outdoorswoman who explores northern Wisconsin from her home base in the Ashland County town of Gingles, may be reached at morrisoutside@gmail.com.
