Below, an unusual picture of a Barn Owl's ear, photographed during the Duhallow Barn Owl Survey this summer. The ear opening is much larger than on comparably sized birds, and the openings are slightly asymmetric on each side of the head, allowing more precise location of sounds.
Barn Owl ear (M.O'Clery).
The heart-shaped facial disc which is so prominent on Barn Owls, is composed of slightly stiffer feathers, and it is believed that these further channel sound toward the ears, further enhancing an already exceptional hearing ability.