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Asio

Genus of birds

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Asio is a genus of typical owls, or true owls, in the family Strigidae. This group has representatives over most of the planet, and the short-eared owl is one of the most widespread of all bird species, breeding in Europe, Asia, North and South America, the Caribbean, Hawaii and the Galápagos Islands. Its geographic range extends to all continents except Antarctica and Australia.

These are medium-sized owls, 30-46 cm (12-18 in) in length with 80-103 cm (31-41 in) wingspans. They are long-winged and have the characteristic facial disc. The two northern species are partially migratory, moving south in winter from the northern parts of their range, or wandering nomadically in poor vole years in search of better food supplies. Tropical Asio owls are largely sedentary. These owls hunt over open fields or grasslands, taking mainly rodents, other small mammals and some birds.

Asio owls are mainly nocturnal, but short-eared owls are also crepuscular. Most species nest on the ground, but the long-eared owl (Asio otus) nests in the old stick nests of crows, ravens and magpies (family Corvidae) and various hawks.

01Taxonomy

The genus Asio was introduced by the French zoologist Mathurin Jacques Brisson in 1760 with the long-eared owl (Asio otus) as the type species. The genus name is from asiō, the Latin name used by Pliny the Younger for a type of horned owl, the feather tufts on the head of these owls give the appearance of "ears" which is a defining characteristic.

02Species

The genus contains the following nine species:

Genus Asio , Brisson, 1760, nine species
Common name Scientific name and subspecies Range Size and ecology IUCN status and estimated population
Jamaican owl Asio grammicus
(Gosse, 1847)
Jamaica
Size:

Habitat:

Diet:
 LC 

Striped owl Asio clamator
(Vieillot, 1808)
South America and parts of Central America.
Size:

Habitat:

Diet:
 LC 

Long-eared owl Asio otus
(Linnaeus, 1758)

Four subspecies
  • A. o. otus (Linnaeus, 1758)
  • A. o. canariensis (Madarász, 1901)
  • A. o. wilsonianus (Lesson, 1830)
  • A. o. tuftsi Godfrey, 1948

Size:

Habitat:

Diet:
 LC 

Abyssinian owl Asio abyssinicus
(Guérin-Méneville, 1843)
Ethiopia and northern Kenya. Size:

Habitat:

Diet:
 LC 

Madagascar owl Asio madagascariensis
(A. Smith, 1834)
Madagascar Size:

Habitat:

Diet:
 LC 

Stygian owl Asio stygius
(Wagler, 1832)

Six subspecies
Mexico, parts of Central America, Cuba, Hispaniola, and 10 countries in South America.
Size:

Habitat:

Diet:
 LC 

Short-eared owl Asio flammeus
(Pontoppidan, 1763)

Eleven subspecies
all continents except Antarctica and Australia
Size:

Habitat:

Diet:
 LC 

Marsh owl Asio capensis
(Smith, 1834)
southern Africa Size:

Habitat:

Diet:
 LC 

Fearful owl Asio solomonensis
(Hartert, 1901)
Solomon Islands archipelago Size:

Habitat:

Diet:
 VU 

Three fossil species are recognized:

The supposed Late Eocene/Early Oligocene eared owl "Asio" henrici has been recognized as a member of the fossil barn-owl genus Selenornis. "Asio" pygmaeus (often misspelt pigmaeus) cannot be assigned to a genus without restudy of the material. "Asio" collongensis (Middle Miocene of Vieux-Collonges, France) is now placed in the genus Alasio.

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Sources and credits

This article is adapted from the Wikipedia article Asio, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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