Gamarús dels Urals , Strix uralensis

Himalayan Owl

Strix nivicolum

The Tawny Owl or Brown Owl (Strix aluco) is a stocky, medium-sized owl commonly found in across much of Eurasia. Its underparts are pale with dark streaks, and the upperparts are either brown or grey. Several of the eleven recognised subspecies have both variants. The nest is typically in a tree hole where it can protect its eggs and young against potential predators. This owl is non-migratory and highly territorial. Many young birds starve if they cannot find a vacant territory once parental care ceases. This nocturnal bird of prey hunts mainly , usually by dropping from a perch to seize its prey, which it swallows whole; in more urban areas its diet includes a higher proportion of birds. Vision and hearing adaptations and silent flight aid its night hunting. The Tawny is capable of catching smaller owls, but is itself vulnerable to the Eagle Owl or Northern Goshawk. Although many people believe this owl has exceptional night vision, its retina is no more sensitive than a human's. Rather, it is its asymmetrically placed ears that are key to its hunting because they give the Tawny Owl excellent directional hearing. Its nocturnal habits and eerie, easily imitated call, have led to a mythical association of the Tawny with bad luck and death.

The Tawny Owl is a robust bird, in length, with an wingspan. Weight can range from . The Tawny Owl flies with long glides on rounded wings, less undulating and with fewer wingbeats than other Eurasian owls, and typically at a greater height.The flight of the Tawny Owl is rather heavy and slow, particularly at its first entering on the wing. As with most owls, its flight is silent because of its feathers' soft, furry upper surfaces and a fringe on the leading edge of the outer primaries. Its size, squat shape and broad wings distinguish it from other owls found within its range; Great Grey, Eagle and are similar in shape, but much larger. An owl's eyes are placed at the front of the head and have a field overlap of 50–70%, giving it better binocular vision than diurnal birds of prey (overlap 30–50%). The owl's actual visual acuity is only slightly greater than that of man, and any increased sensitivity is due to optical factors rather than to greater retinal sensitivity; both humans and owl have reached the limit of resolution for the retinas of terrestrial . Field of view compared with a pigeon Adaptations to night vision include the large size of the eye, its tubular shape, large numbers of closely packed retinal rods, and an absence of , since have superior light sensitivity. There are few coloured oil drops, which would reduce the light intensity. Hearing is important for a nocturnal bird of prey, and as with other owls, the Tawny's two ear openings differ in structure and are asymmetrically placed to improve directional hearing. A passage through the skull links the eardrums, and small differences in the time of arrival of a sound at each ear enables its source to be pinpointed. The left ear opening is higher on the head than the larger right ear and tilts downward, improving sensitivity to sounds from below. Both ear openings are hidden under the facial disk feathers, which are structurally specialized to be transparent to sound, and are supported by a movable fold of skin (the pre-aural flap). An owl's retina has a single fovea.Based on Güntürkün, Onur, "Structure and functions of the eye" in 1–18 The internal structure of the ear, which has large numbers of auditory , gives an improved ability to detect low-frequency sounds at a distance, which could include rustling made by prey moving in vegetation. The Tawny Owl's hearing is ten times better than a human's, and it can hunt using this sense alone in the dark of a woodland on an overcast night, but the patter of raindrops makes it difficult to detect faint sounds, and prolonged wet weather can lead to starvation if the owl cannot hunt effectively. The commonly heard contact call is a shrill, kew-wick but the male has a quavering advertising song hoo...ho, ho, hoo-hoo-hoo-hoo. William Shakespeare used this owl's song in Love's Labour's Lost (Act 5, Scene 2) as "Then nightly sings the staring owl, Tu-whit; Tu-who, a merry note, While greasy Joan doth keel the pot", but this stereotypical call is actually a duet, with the female making the kew-wick sound, and the male responding hooo. The call is easily imitated by blowing into cupped hands through slightly parted thumbs, and a study in Cambridgeshire found that this mimicry produced a response from the owl within 30 minutes in 94% of trials. A male’s response to a broadcast song appears to be indicative of his health and vigour; owls with higher blood parasite loads use fewer high frequencies and a more limited range of frequencies in their responses to an apparent intruder.


Himalayan Owl photos and videos:



Strix [aluco or nivicolum] - Avibase
Order: Strigiformes Family: Strigidae. English: Tawny Owl Scientific: Strix [aluco or nivicolum] Protonym: Strix Aluco. Avibase ID: 2CD9FB4AE9C1214A

Himalayan Wood-Owl - Strix nivicola
Strix nivicola;Himalayan Wood-Owl;Indian Birds ... nivicolum; Himalayan Wood Owl; ; Syrnium nivicolum; Himalayan Wood-Owl; ; Syrnium nivicola; Himalayan Wood-Owl; ; Strix ...
Strix aluco Himalayan Owl: Strix nivicolum: AS : Hume's Owl: Strix butleri Spotted Owl: Strix occidentalis Northern Barred Owl: Strix varia Mexican Barred Owl

Strigidae – Owls « Lee's Birdwatching Adventures Plus
Himalayan Owl (Strix nivicolum) ____ (Strix nivicolum nivicolum) ____ (Strix nivicolum yamadae) ____ (Strix nivicolum ma) Hume’s Owl (Strix butleri)

Tawny Owl, Strix aluco; Himalayan Owl, Strix nivicolum; Mottled Wood-Owl, Strix ocellata; Spotted Wood-Owl, Strix seloputo; Brown Wood-Owl, Strix leptogrammica

Famille des Strigidés - Les oiseaux
Strix uralensis: Ural Owl: Chouette de Tengmalm: Aegolius funereus: Boreal Owl: Chouette des neiges: Strix nivicolum: Himalayan Owl: Chouette des pagodes: Strix seloputo

Global Species : Strix aluco (Tawny Owl)
Strix aluco nivicolum Strix aluco sanctinicolai Strix aluco siberiae Strix aluco sylvatica (European tawny owl) Strix aluco willkonskii Strix aluco yamadae

Himalayan Wood-Owl - BirdForum
Strix leptogrammica newarensis is the Himalayan Wood-Owl Strix aluco nivicolum is the Himalayan Tawny Owl
Strix nivicola. Himalayan Owl. Strix nivicolum. TAX. H&M Corrigenda 2.1, fide Norman David. 96. Pipra pipra. White-crowned Manakin. Dixiphia pipra. TAX. Tello et al 2009

Strix – Wikipedia, wolna encyklopedia
puszczyk zwyczajny (Strix aluco) puszczyk leśny (Strix nivicolum) puszczyk arabski (Strix butleri) puszczyk plamisty (Strix occidentalis) puszczyk kreskowany (Strix varia)

Aves—A Taxonomy in Flux: 2009 Updates
There are two spelling corrections to scientific names: Gray-chested Dove, Leptotila cassinii, not cassini, and Himalayan Owl, Strix nivicolum, not nivicola.

Strix - Wikipedia
Strix nivicolum; Strix occidentalis (Gevlekte bosuil) Strix ocellata (Indische bosuil) Strix rufipes (Roodpootbosuil) Strix seloputo (Maleise bosuil) Strix uralensis ; Strix varia ...

Full text of "Check-list of birds of the world"
Full text of "Check-list of birds of the world"

Strix - Wikipédia
Strix aluco – Chouette hulotte; Strix nivicolum – Chouette des neiges; Strix butleri – Chouette de Butler; Strix occidentalis – Chouette tachetée

Strigidae – Wikipédia, a enciclopédia livre
Strix nivicolum; Strix butleri - Coruja-da-palestina; Strix occidentalis; Strix varia; Strix fulvescens; Strix hylophila - Coruja-listrada; Strix rufipes; Strix chacoensis

Les oiseaux d'Inde
Strix nivicolum: Himalayan Owl: Chouette hulotte: Strix aluco: Tawny Owl: Chouette leptogramme: Strix leptogrammica: Brown Wood Owl: Chouette ocellée: Strix ocellata

xeno-canto :: bird sounds from around the world
Strix aluco: Himalayan Owl: Strix nivicolum: Hume's Owl: Strix butleri: Spotted Owl: Strix occidentalis: Northern Barred Owl: Strix varia: Mexican Barred Owl: Strix sartori

Bosuil - Strix Aluco - Eaglewatch roofvogels en uilen - Roofvogels ...
Strix aluco obscurata Strix aluco sanctinicolai Strix aluco haermsi Strix nivicolum Strix nivicolum nivicolum Strix nivicolum obrieni

Strigidae - Wikipédia
Strix aluco – Chouette hulotte; Strix nivicolum – Chouette des neiges; Strix butleri – Chouette de Butler; Strix occidentalis – Chouette tachetée

Gamarús - Viquipèdia
Strix aluco nivicolum (Blyth, 1845) Strix aluco sanctinicolai (Zarudny, 1905) Strix aluco siberiae (Dementiev, 1933) Strix aluco sylvatica (Shaw, 1809)

© 2014 | Disclaimer