What does the Eastern Screech-Owl sound like at night?
Press play. If that is the sound outside, you have your answer — the Eastern Screech-Owl's "tremolo trill".
What you're hearing
A soft, even-pitched trill (sometimes called a "bounce song") that lasts 3–6 seconds. It's a gentle, purring trill on one note, used by pairs to stay in contact and by males when courting a mate. Often two owls (a mated pair) will trill to each other in a duet, especially in the early breeding season.
“tremolo trill”
Birders often file this one under Trill (Song).
What time of night you hear it
Full dark, all year, and often from a suburban tree far closer to your window than you expect.
Strictly nocturnal, roosting silently by day in tree cavities.
Why an Eastern Screech-Owl calls at night
That long, even, purring trill is the one you're hearing — screech-owls use it to keep tabs on each other, and pairs will trill back and forth. The other voice, the eerie descending whinny, is the territorial one. This is the owl behind most "something is trembling in my yard at night" reports, because it is small, common in towns, and happy in a backyard oak. It does not screech, despite the name.
What else could it be?
The other voices you are most likely to hear in the dark. Play them and compare.
Western Screech-Owl
Nearly identical in size and shape, but found in western North America. Visually, Western Screech-Owls have very similar plumage (also gray or reddish morphs) and also have ear tufts. Range is usually the determining factor. Their vocalizations differ: the Western gives a series of accelerating hoots (like a bouncing ball) rather than the Eastern's whinny trill. In the very limited areas of range overlap (e.g., parts of Texas), voice is the best way to distinguish them.
Northern Saw-whet Owl
Another small owl sharing some range in the East. Saw-whet Owls are even smaller and lack ear tufts. They have a round head, brown upperparts with white spots, and streaky underparts. Saw-whets have dark brown eyes (as opposed to the Screech-Owl's yellow eyes). Their call is a series of monotonic tooting whistles, very unlike the Screech-Owl's trill or whinny. They also prefer dense forests and are migratory, whereas Screech-Owls are resident and found even in suburban areas.
Barred Owl
Who cooks for you? Who cooks for you-all?