Distinguishing Characteristics

Medium-sized owl with females larger than males (about 20% larger in body mass: 378 vs. 315 g), although Snyder and Wiley (1976) report this species to be relatively non-dimorphic in size (e.g., wing length roughly equal: 296 mm vs 297 mm). Adult plumage dorsally mottled brown and buff, resembles dried grasses. Ventrally, whitish to rust colored with dense vertical streaking on breast, thinning out on sides and flanks. Females generally darker dorsally owing to more brown, and ventrally owing to rust color and heavier streaking, but there is overlap and sexes are not reliably distinguished by plumage (Pyle 1997). Sexes more readily distinguished during the breeding season using color, size, and behavior (Village 1987, Holt 1992). Head large and round with very small tufts arising from center of forehead, generally not seen. Face large and facial ruff round during normal posture. Facial disk gray/white, orbits black, eyes yellow, bill black. Wings long and broad with 10 primaries and 12 secondaries. Tail medium length with 12 feathers. In ascending flight, bouncing high flapping wing-beats. When hunting, few wing-beats interspersed with quartering on slightly positive dihedral wings. Aerial agility a good field characteristic of this species as it is often seen foraging during the day. 

Juveniles (male and female similar in plumage) like adults but upperparts and head more dusky with buff tips; facial pattern of adult lacking; iris more brown than yellow (Pyle 1997).

Morphologically similar to Long-eared Owl (Asio otus), but larger overall. Long-eared Owl’s flight is more direct with wings held most often on horizontal plane. Long-eared Owl plumage darker dorsally and more heavily streaked and barred ventrally (Davis and Prytherch 1976). Usually separated by diel activity period (i.e. Long-eared: nocturnal; Short-eared: crepuscular), but latitude and season may complicate this.