Búho del Chaco

Identificación

The Chaco owl is 35 to 38 cm (14 to 15 in) long. Males weigh 360 to 435 g (12.7 to 15.3 oz) and females 420 to 500 g (15 to 18 oz). It has a round head with no ear tufts. Adults have a pale grayish white facial disk with concentric dark lines. Their upperparts are dusky brownish black with narrow white and yellowish buff barring. Their underparts are off-white with dark brown barring. The tail is dark grayish brown with narrow pale bars.

Taxonomía

The Chaco owl was originally described as a species, then quickly reclassified as a subspecies of rufous-legged owl (Strix rufipes). A 1995 paper provided strong morphological and vocal evidence that the original treatment as a species in its own right was correct. Later work showed that it is probably more closely related to the rusty-barred owl (S. hylophila) than to the rufous-legged. It is monotypic.

Nombre científico

Strix chacoensis

Autoridad

Cherrie & Reichenberger, 1921

Orden

Strigiformes

Familia

Strigidae

Género

Strix

Distribución y hábitat

The Chaco owl is found in southern South America, from Bolivia's Santa Cruz Department south through western Paraguay into north-central Argentina as far as Córdoba and Buenos Aires provinces. Its elevational range is not well known, but in Argentina it is found between 500 and 1,300 m (1,600 and 4,300 ft). It inhabits the Gran Chaco, a biome characterized by low rainfall. The species is found there in hilly, rolling, and flat terrain with a wide variety of forest types, both dense and semi-open.

Migración

Resident species

Comportamiento

The Chaco owl is primarily nocturnal but is vocally active at dawn and dusk. It hunts from a perch, dropping on or flying to small mammals, birds, reptiles, and invertebrates.<p>The Chaco owl's breeding phenology is poorly known but is assumed to be similar to that of other Strix owls. It probably nests in tree cavities or possibly holes in the ground. Captive females lay two to three eggs.<p>The male Chaco owl's song is a "rather frog-like crococro craorr-craorr craorr-craorr, with emphasis on the first craorr". The female's song is similar but higher pitched.

Conservación

Tendencia poblacional

declining