Here's a recording of a male Long-eared Owl in full song, at a woodland site near Newmarket, on Wednesday last.
As dusk falls, a few birds are still singing, but the song of a male Long-eared Owl is subtle and easily missed. It can sound a little like a distant cow mooing, a regular "Oooo", repeated every three seconds or so. Although it is a relatively quiet call, it can carry, and on this still evening was audible from about 300-350m away. This recording was taken when the bird was only about 80m away, hidden in the foliage. The song was repeated for two to four minutes, then the male would fly to a new perch and start again, but during the flight, loud wingclaps could be heard, another way that males lay claim to their territory.