Points North Field Guide: Snowy Owls “They can be above and up in a tree and listen to the critters munching on grass, traveling along their trails underneath the snow pack," explains Kaitlyn Bohnet, director of North Sky Raptor Sanctuary. "[Owls] triangulate where they are and then hit them through the snow pack.” Owls can detect mice with such precision in part because their ears are asymmetrical. The right ear is a little larger and positioned a bit higher than the left ear. Sound hits one ear before the other and that helps the owl pinpoint the location of its prey.