Asio

Taxobox
name = "Asio"


image_width = 200px
image_caption = Long-eared Owl
regnum = Animalia
phylum = Chordata
classis = Aves
ordo = Strigiformes
familia = Strigidae
genus = "Asio"
genus_authority = Brisson, 1760
subdivision_ranks = Species
subdivision = See text.

"Asio" is a genus of typical owls, or true owls, in family Strigidae. The genus "Asio" contains the eared owls, which are characterised by feather tufts on the head which have the appearance of ears. 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 in length with 80-103 cm 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.

"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.

These owls hunt over open fields or grasslands, taking mainly rodents, other small mammals and some birds.

pecies

* Stygian Owl, " Asio stygius"
* Long-eared Owl, " Asio otus"
* African Long-eared Owl, " Asio abyssinicus"
* Madagascar Long-eared Owl, " Asio madagascariensis"
* Short-eared Owl, " Asio flammeus"
* Marsh Owl, " Asio capensis"
* Striped Owl, "Asio clamator" - often placed in "Pseudoscops" or "Rhinoptynx"

Two fossil species are recognized nowadays:
* "Asio brevipes" (Glenns Ferry Late Pliocene of Hagerman, USA)
* "Asio priscus" (Late Pliocene of Santa Rosa Island, USA)

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".(Mlíkovský 2002)

References

* Mlíkovský, Jirí (2002): "Cenozoic Birds of the World, Part 1: Europe". Ninox Press, Prague. ISBN 80-901105-3-8 [http://www.nm.cz/download/JML-18-2002-CBE.pdf PDF fulltext]