Great Grey Owl

The Great Grey Owl holds the distinction of being the longest owl species in the world, though much of its apparent bulk comes from dense, fluffy plumage rather than actual body mass - it is lighter than the similarly sized Great Horned Owl or Eurasian Eagle-Owl.

It inhabits boreal forest and adjoining meadows across North America, Scandinavia, and Siberia, hunting small rodents by sound with extraordinary precision, even through snow.

Its plumage is entirely grey-toned, finely mottled for camouflage against conifer bark, with a distinctively large facial disc marked by concentric dark rings around small yellow eyes.

Recognizing the feathers

• Body feathers are grey with fine, dense mottling in darker grey and white - lacking the browns or rufous tones seen in many other owls.
• Facial disc feathers form an unusually large disc marked with narrow concentric dark rings, a feature distinctive to this species.
• Flight feathers are very large, broad, and soft-fringed, among the biggest of any owl by feather length, reflecting the bird's long overall size.
• Tail feathers are long, contributing to the species' record length, with fine grey barring.

Similar species

• The predominantly grey (not brown or rufous) tone and huge, ringed facial disc separate this species' feathers from Great Horned Owl and Eurasian Eagle-Owl feathers; lack of ear tufts separates it from those species as well.

Plumage

Adults are uniformly grey with fine mottling throughout, a large facial disc marked with dark concentric rings, and small yellow eyes appearing proportionally tiny relative to the huge head. Sexes look alike, with females larger.

Juveniles are downier and more diffusely patterned before acquiring the adult grey mottled plumage.

Molt occurs gradually over the summer months, with flight feathers replaced in sequence.

Habitat & range

Found across the boreal forest belt of North America (Alaska and Canada, extending into the northern US) and across Scandinavia and Siberia, typically near forest edges and adjoining meadows or bogs used for hunting.

Mostly non-migratory, though it can shift locations irregularly in response to rodent population cycles, sometimes appearing well south of its usual range in poor food years.

Behavior & field notes

Hunts primarily voles and other small rodents, using extraordinarily acute hearing to detect prey moving beneath snow, then plunging through the snow to catch it.

Its call is a series of deep, soft hoots, quieter and lower-pitched than many other large owls.

A large, uniformly grey, finely mottled feather, especially one showing narrow concentric ring patterning if from the facial disc, found near boreal forest meadows, is a strong indicator of this species.