Chaco Owl

The Chaco Owl is a medium-sized owl found in the Gran Chaco region of South America, spanning parts of Argentina, Paraguay, and Bolivia. It belongs to the genus Strix, the earless 'true owls,' and is closely related to the Rufous-legged Owl of more temperate southern South America.

Its plumage is well suited to the dry, thorny woodland habitat of the Chaco, blending dense barring and mottling that matches the dappled light of open scrub forest.

Feathers of this species can be recognized by their combination of dark round eyes (no ear tufts), even barring across the wings and tail, and an overall brown tone matching the arid woodland it inhabits.

Size and shape

• Rounded head profile feathers with no ear tufts, typical of Strix owls
• Broad, rounded flight feathers and a moderately long, evenly barred tail

Color and pattern

• Ground color greyish-brown to warmer brown, with dense, fairly regular dark barring across the back, wings, and tail
• Underparts paler with fine streaking and barring rather than solid color
• Facial disc feathers plain brown-grey without strong contrasting rings

Distinguishing from similar species

• Closely resembles the Rufous-legged Owl of the southern Andes and Patagonia, but the two occupy largely separate, non-overlapping dry versus humid habitats
• Overall duller and more evenly barred than tropical screech-owls sharing its range, which tend to show more contrast and ear tufts

Plumage is greyish-brown to warm brown overall, densely barred and mottled to blend with dry woodland bark and shadow. Sexes look similar, with females typically slightly larger, as is standard among owls. Juveniles show a softer, more uniformly downy version of the adult pattern before fledging into adult-like barring. Molt is gradual and generally follows the breeding season.

Restricted to the Gran Chaco ecoregion of central South America, including parts of Argentina, Paraguay, and Bolivia, where it inhabits dry deciduous woodland and thorn scrub forest. It is a non-migratory resident, remaining in suitable Chaco woodland year-round.

A nocturnal hunter taking a range of small vertebrates and large insects from perches within dry woodland. It nests in tree cavities. Its voice consists of low hooting calls typical of Strix owls, used to establish and defend territory at night. Because it closely resembles the Rufous-legged Owl, any feather tentatively assigned to this species should be considered together with its geographic origin within the dry Chaco region specifically.