''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 The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...

is one of the most widespread of all bird species, breeding in Europe, Asia, North and South America, the

Caribbean The Caribbean (, ) ( es, El Caribe; french: la Caraïbe; ht, Karayib; nl, De Caraïben) is a region of the Americas that consists of the Caribbean Sea, its islands (some surrounded by the Caribbean Sea and some bordering both the Caribbean Se ...

, Hawaii and the Galápagos Islands. Its geographic range extends to all continents except Antarctica and

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. These are medium-sized owls, in length with 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

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s and some birds. ''Asio'' owls are mainly

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

, but short-eared owls are also

crepuscular In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of daylig ...

. Most species nest on the ground, but the long-eared owl ('' Asio otus'') nests in the old stick nests of crows,

raven A raven is any of several larger-bodied bird species of the genus ''Corvus''. These species do not form a single taxonomic group within the genus. There is no consistent distinction between "crows" and "ravens", common names which are assigned t ...

s and

magpie Magpies are birds of the Corvidae family. Like other members of their family, they are widely considered to be intelligent creatures. The Eurasian magpie, for instance, is thought to rank among the world's most intelligent creatures, and is one ...

s (family Corvidae) and various

hawk Hawks are bird of prey, birds of prey of the family Accipitridae. They are widely distributed and are found on all continents except Antarctica. * The subfamily Accipitrinae includes goshawks, sparrowhawks, sharp-shinned hawks and others. Th ...

Taxonomy

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 Gaius Plinius Caecilius Secundus, born Gaius Caecilius or Gaius Caecilius Cilo (61 – c. 113), better known as Pliny the Younger (), was a lawyer, author, and magistrate of Ancient Rome. Pliny's uncle, Pliny the Elder, helped raise and educate ...

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.

Species

The genus contains the following nine species: * Jamaican owl, ''Asio grammicus'' (formerly placed in ''Pseudoscops'') * Striped owl, ''Asio clamator'' (formerly placed in ''Pseudoscops'' or ''Rhinoptynx'') * Long-eared owl, ''Asio otus'' *

Abyssinian owl The Abyssinian owl or African long-eared owl (''Asio abyssinicus'') is a medium-sized true owl.Burton, John A. 1984. "Owls of the world: their evolution, structure and ecology (Rev. Ed.)". Tanager Books Description The Abyssinian owl has dark bro ...

, ''Asio abyssinicus'' * Madagascar owl, ''Asio madagascariensis'' * Stygian owl, ''Asio stygius'' *

Short-eared owl The short-eared owl (''Asio flammeus'') is a widespread grassland species in the family Strigidae. Owls belonging to genus ''Asio'' are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or ...

, ''Asio flammeus'' *

Marsh owl The marsh owl (''Asio capensis'') is a medium to large species of owl in the family Strigidae. Description Medium-sized, dark brown with a pumpkin-shaped head with small 'ear' tufts. The facial disc is pale buff, with a distinct dark brown ri ...

, ''Asio capensis'' * Fearful owl, ''Asio solomonensis'' Three fossil species are recognized: * ''Asio brevipes'' (Glenns Ferry Late Pliocene of Hagerman, USA) * ''Asio priscus'' (Late Pleistocene of San Miguel Island and Santa Rosa Island, USA) * ''

Asio ecuadoriensis ''Asio ecuadoriensis'' is an extinct species of eared owl from the Pleistocene of Ecuador. Known from bones of the legs, it was a robust predatory bird similar in size to the great horned owl. Based on the robustness of its limbs and the bone ...

'' (Late Pleistocene of Ecuador)Lo Coco, G.E., Agnolín, F.L. & Román Carrión, J.L.
Late Pleistocene owls (Aves, Strigiformes) from Ecuador, with the description of a new species
In: J Ornithol 161, pp 713–721; March 5, 2020; doi:10.1007/s10336-020-01756-x 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, Jirí (2002):
Cenozoic Birds of the World, Part 1: Europe
''. Ninox Press, Prague.

References

{{Taxonbar, from=Q648422 Bird genera