The
Tawny Owl (
Strix aluco) is a stocky, medium-sized
owlThe Owls are the order Strigiformes, comprising 200 birds of prey, species. Most are solitary, and nocturnal, with some exceptions . Owls hunt mostly small mammals, insects, and other birds, though a few species specialize in hunting fish. They are found in all regions of the Earth except...
which is common in
woodlandsWoodlands may refer to:* Woodland* Eastern Woodlands tribes, some indigenous peoples of North AmericaWoodlands may also refers to places:In Australia*Woodlands, New South Wales*Woodlands, Western AustraliaIn Canada*Woodlands, North Vancouver...
across much of
EurasiaEurasia is a large landmass covering about 52,990,000 km
2 or about 10.6% of the Earth's surface...
. Its underparts are pale with dark streaks, and the upperparts are either brown or grey, with several of the eleven recognised
subspeciesSubspecies in biological classification, is 1) a taxonomic rank subordinate to species, or 2) a taxonomic unit, a taxon in that rank...
having both variants. The
nestA bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term is popular in reference to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
is typically in a tree hole, and eggs and young are fiercely defended against potential predators. This owl is
non-migratoryBird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. These however are usually irregular or in only one direction and are termed variously as nomadism, invasions,...
and highly territorial, and many young birds starve if they cannot find a vacant territory once parental care ceases.
This nocturnal
bird of preyBirds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as any bird that kills its prey with its talons. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases,...
hunts mainly
rodentRodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s, usually by dropping from a perch to seize its victim, which is swallowed whole, although in more urban areas its diet includes a higher proportion of birds.
The
Tawny Owl (
Strix aluco) is a stocky, medium-sized
owlThe Owls are the order Strigiformes, comprising 200 birds of prey, species. Most are solitary, and nocturnal, with some exceptions . Owls hunt mostly small mammals, insects, and other birds, though a few species specialize in hunting fish. They are found in all regions of the Earth except...
which is common in
woodlandsWoodlands may refer to:* Woodland* Eastern Woodlands tribes, some indigenous peoples of North AmericaWoodlands may also refers to places:In Australia*Woodlands, New South Wales*Woodlands, Western AustraliaIn Canada*Woodlands, North Vancouver...
across much of
EurasiaEurasia is a large landmass covering about 52,990,000 km
2 or about 10.6% of the Earth's surface...
. Its underparts are pale with dark streaks, and the upperparts are either brown or grey, with several of the eleven recognised
subspeciesSubspecies in biological classification, is 1) a taxonomic rank subordinate to species, or 2) a taxonomic unit, a taxon in that rank...
having both variants. The
nestA bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term is popular in reference to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
is typically in a tree hole, and eggs and young are fiercely defended against potential predators. This owl is
non-migratoryBird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. These however are usually irregular or in only one direction and are termed variously as nomadism, invasions,...
and highly territorial, and many young birds starve if they cannot find a vacant territory once parental care ceases.
This nocturnal
bird of preyBirds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as any bird that kills its prey with its talons. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases,...
hunts mainly
rodentRodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s, usually by dropping from a perch to seize its victim, which is swallowed whole, although in more urban areas its diet includes a higher proportion of birds. Its night hunting is aided by vision and hearing adaptations and silent flight. The Tawny is capable of catching smaller owls, but may itself be killed by the Eagle Owl or Northern Goshawk, and
foxesThe red fox is a mammal of the order Carnivora. It has the widest range of any terrestrial carnivore, being native to Canada, Alaska, almost all of the contiguous United States, Europe, North Africa and almost all of Asia, including Japan. In Ireland and the UK, where there are no longer any other...
are an important cause of mortality in newly fledged young.
Although this owl is often claimed to have exceptional night vision, its
retinaThe vertebrate retina is a light sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
is no more sensitive than a human's, but its asymmetrically placed ears give the Tawny Owl excellent directional hearing. Its nighttime habits and eerie, easily imitated call have led to an association in myth with bad luck and death.
Description
The Tawny Owl is a robust bird, 37–43
cmA centimetre is a unit of length in the metric system, equal to one hundredth of a metre, which is the current SI base unit of length. Centi is the SI prefix for a factor of...
(14.5–17
inAn inch is the name of a unit of length in a number of different systems, including Imperial units, and United States customary units. There are 36 inches in a yard and 12 inches in a foot...
) in length with an 81–96 cm (32–38 in) wingspan. Its large rounded head lacks ear tufts, and the facial disc surrounding the dark brown eyes is usually rather plain. The nominate race has two morphs which differ in their
plumagePlumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
colour, one form having rufous brown upperparts and the other greyish brown, although intermediates also occur. The underparts of both morphs are whitish and streaked with brown. This species is
sexually dimorphicSexual dimorphism is the systematic difference in form between individuals of different sex in the same species. Examples include colour , size, and the presence or absence of parts of the body used in courtship displays or fights, such as ornamental feathers, horns, antlers or tusks.-Examples:In...
; the female is much larger than the male, 5% longer and more than 25% heavier.
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. As with most owls, its flight is silent due to its feathers' soft, furry upper surfaces and a fringe on the leading edge of the outer primaries. Its size, dumpy shape and broad wings distinguish it from other owls found within its range;
Great GreyThe Great Grey Owl or Lapland Owl is a very large owl, distributed across the Northern Hemisphere.-Description:Adults have a big, rounded head with a grey face and yellow eyes with darker circles around them. The underparts are light with dark streaks; the upper parts are grey with pale bars...
, Eagle and
Ural OwlThe Ural Owl is a medium-large nocturnal owl of the genus Strix, with up to 15 subspecies found in Europe and northern Asia....
s 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 visionBinocular vision is vision in which both eyes are used together. The word binocular comes from two Latin roots, bini for double, and oculus for eye. Having two eyes confers at least four advantages over having one. First, it gives a creature a spare eye in case one is damaged. Second, it gives a...
than diurnal birds of prey (overlap 30–50%). The Tawny Owl's
retinaThe vertebrate retina is a light sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
has about 56,000 light-sensitive
rod cellRod cells, or rods, are photoreceptor cells in the retina of the eye that can function in less intense light than can the other type of photoreceptor, cone cells. Because they are more light sensitive, rods are responsible for night vision. Named for their cylindrical shape, rods are concentrated...
s per square millimetre (36 million per square inch); although earlier claims that it could see in the
infraredInfrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light , but shorter than that of terahertz radiation and microwaves...
part of the
spectrumThe electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
have been dismissed, it is still often said to have
eyesightVision is the most important sense for birds, since good eyesight is essential for safe flight, and this group has a number of adaptations which give visual acuity superior to that of other vertebrate groups; a pigeon has been described as "two eyes with wings". The avian eye resembles that of a...
10 to 100 times better than humans in low-light conditions. However, the experimental basis for this claim is probably inaccurate by at least a factor of 10. 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
vertebrateVertebrates are members of the subphylum Vertebrata, chordates with backbones or spinal columns. About 58,000 species of vertebrates have been described. Vertebrata is the largest subphylum of chordates, and contains many familiar groups of large land animals. Vertebrates comprise cyclostomes, bony...
s.
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
cone cellCone cells, or cones, are photoreceptor cells in the retina of the eye that function best in relatively bright light. The cone cells gradually become sparser towards the periphery of the retina....
s, since colour vision is unnecessary at night. There are few coloured oil drops, which would reduce the light intensity. Unlike diurnal birds of prey, owls normally have only one
foveaThe term fovea comes from the Latin, meaning pit or pitfall. As an anatomical term, there are several foveae around the body, including in the head of the femur.Fovea of the eye=...
, and that is poorly developed except in diurnal hunters like the
Short-eared OwlThe Short-eared Owl is a species of typical owl . 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 may not be visible. Asio flammeus will display its tufts when in a defensive pose. However, its very short...
.
Hearing is important for a nocturnal
bird of preyBirds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as any bird that kills its prey with its talons. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases,...
, 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).
The internal structure of the ear, which has large numbers of auditory
neuronA neuron is an excitable cell in the nervous system that processes and transmits information by electrochemical signaling. Neurons are the core components of the brain, the vertebrate spinal cord, the invertebrate ventral nerve cord, and the peripheral nerves...
s, 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 ShakespeareWilliam Shakespeare was an English poet and playwright, widely regarded as the greatest writer in the English language and the world's preeminent dramatist. He is often called England's national poet and the "Bard of Avon"...
immortalised this owl's song in Love's Labour's LostLove's Labour's Lost is one of William Shakespeare's early comedies, believed to have been written in the mid-1590s, and first published in 1598.-Etymology:The name of the play comes from a poem written by the Greek Theognis:...
(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 stereotypicalA stereotype is a commonly held public belief about specific social groups, or types of individuals.The concepts of "stereotype" and "prejudice" are often confused with many other different meanings. Stereotypes are standardized and simplified conceptions of groups, based on some prior...
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 CambridgeshireCambridgeshire is a county in England, bordering Lincolnshire to the north, Norfolk to the northeast, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west...
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.
Geographical variation
Although both colour morphs occur in much of the European range, brown birds predominate in the more humid climate of western Europe, with the grey phase becoming more common further east; in the northernmost regions, all the owls are a cold-grey colour. SiberiaSiberia , is the vast region constituting almost all of Northern Asia and for the most part currently serving as the massive central and eastern portion of the Russian Federation, having served in the same capacity previously for the USSR from its beginning, and the Russian Empire beginning in the...
n and Central AsiaAsia is a region of Asia from the Caspian Sea in the west to central China in the east, and from southern Russia in the north to northern India in the south. It is also sometimes known as Middle Asia or Inner Asia, and is within the scope of the wider Eurasian continent.Various definitions of its...
n subspecies have grey and white plumage, the North AfricaNorth Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa.Geopolitically, the UN definition of Northern Africa includes the following seven countries or territories; Algeria, Egypt, Libya, Morocco, Sudan, Tunisia,Mauritania, and...
n race is dark grey-brown, and SouthSouth Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries on the west and the east...
and East Asian birds have barred, not striped, underparts, and fine lines around the facial disc. The Siberian and ScandinaviaScandinavia is a geographical region in northern Europe that includes, and is named after, the Scanian Province. It consists of the kingdoms of Norway, Sweden, and Denmark...
n subspecies are 12% larger, 40% heavier, and have 13% longer wings than western European birds, in accordance with Bergmann's ruleIn zoology, Bergmann's rule is an ecogeographic rule that correlates latitude with body mass in animals. Broadly it asserts that within a species the body mass increases with latitude and colder climate, or that within closely related species that differ only in relation to size that one would...
which predicts that northern forms will typically be bigger than their southern counterparts.
The plumage colour is geneA gene is the basic unit of heredity in a living organism. All living things depend on genes. Genes hold the information to build and maintain their cells and pass genetic traits to offspring...
tically controlled, and studies in Finland and Italy indicate that grey morph Tawny Owls have more reproductive success, better immune resistance, and fewer parasitesParasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the host....
than brown birds. Although this might suggest that eventually the brown morph could disappear, the owls show no colour preference when choosing a mate, so the adverse selection pressure is reduced. There are also environmental factors involved. The Italian study showed that brown-morph birds were found in denser woodland, and in Finland, Gloger's ruleGloger's Rule is a zoological rule which states that within a species of endotherms, more heavily pigmented forms tend to be found in more humid environments, e.g. near the equator...
would suggest that paler birds would in any case predominate in the colder climate.
Taxonomy
This species was first described by LinnaeusCarl Linnaeus was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature...
in his Systema naturaeThe book Systema Naturae was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. Its full title is Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis or translated: "System of...
in 1758 under its current scientific name. The binomialThe formal system of naming species is called binominal nomenclature , binary nomenclature , or the binomial classification system...
derives from GreekGreek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical...
strix "owl" and ItalianItalian is a Romance language spoken by about 60 million people in Italy, and by a total of around 70 million in the world. In Switzerland, Italian is one of four official languages. It is also the official language of San Marino, as well as the primary language of Vatican City...
allocco, "Tawny Owl" (from LatinLatin is an Italic language originally spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe...
ulucus "screech-owl").
The Tawny Owl is a member of the wood-owl genus StrixStrix is a genus of owls. They belong to the typical owl family Strigidae, one of the two generally accepted living families of owls, with the other being the barn-owls . Common names are earless owls or wood-owls though they are not the only owls without ear tufts, and "wood owl" is also used as a...
, part of the typical owl family Strigidae, which contains all species of owl other than the barn owlsBarn-owls are one of the two families of owls, the other being the typical owls, Strigidae. They are medium to large sized owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons...
. Within its genus, the Tawny's closest relatives are Hume's OwlThe Hume’s Owl or Hume’s Tawny Owl is a species of owl. As its alternative name implies, it is closely related to the more widespread Tawny Owl....
, Strix butleri, (formerly considered to be conspecificConspecificity is a concept in biology. Two or more individual organisms, populations, or taxa are termed conspecific if they belong to the same species....
), its larger northern neighbour, the Ural OwlThe Ural Owl is a medium-large nocturnal owl of the genus Strix, with up to 15 subspecies found in Europe and northern Asia....
, S. uralensis, and the North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
n Barred OwlThe Barred Owl, Strix varia, is a large typical owl. It goes by many other names, including eight hooter, rain owl, wood owl, and striped owl, but is probably known best as the hoot owl.-Description:...
, S. varia. The EarlyCalabrian is a subdivision of the Pleistocene Epoch of the Geologic time scale. The beginning of the stage is defined at 1.806 Ma . The end of the stage is defined by the last magnetic pole reversal 781,000 ± 5,000 years ago. Originally the Calabrian was a European faunal stage primarily based on...
–Middle PleistoceneThe Pleistocene Series is not subdivided into formal stages. Several solutions have been proposed, and dedicated working groups are presently pursuing an agreed solution. Although the base of the Pleistocene, before 2009, had been established at Vrica , the addition of the earlier Gelasian that...
Strix intermedia is sometimes considered a paleosubspecies of the Tawny Owl, which would make it that species' immediate ancestor.
The Tawny Owl subspecies are often poorly differentiated, and may be at a flexible stage of subspecies formation with features related to the ambient temperature, the colour tone of the local habitat, and the size of available prey. Consequently, various authors have described between 10 and 15 subspecies. The currently recognised subspecies are listed below.
| Subspecies |
Range |
Described by (parentheses indicate originally in a different genus) |
| S. a. aluco |
N & C EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
from Scandinavia to the Mediterranean and Black Seaur a loser!The Black Sea is an inland sea bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and Aegean Seas and various straits. The Bosporus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects it to...
|
Linnaeus, 1758 |
| S. a. sylvatica |
W EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural River, the Caspian Sea, the Caucasus Mountains , and the Black Sea to the southeast...
including Great BritainGreat Britain is an island lying to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island. With a population of about 59.6 million people, it is the third most populated island on Earth. Great Britain is surrounded by over 1000 smaller...
|
ShawGeorge Shaw was an English botanist and zoologist.Shaw was born at Bierton, Buckinghamshire and was educated at Magdalen Hall, Oxford, receiving his M.A. in 1772. He took up the profession of medical practitioner. In 1786 he became the assistant lecturer in botany at Oxford University...
, 1809 |
| S. a. nivicola |
NepalNepal , officially the Federal Democratic Republic of Nepal, is a landlocked country in South Asia and the world's youngest republic. It is bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...
to SE ChinaChina is a cultural region, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
, south to N Burma and ThailandThe Kingdom of Thailand is an independent country that lies in the heart of Southeast Asia.It is bordered to the north by Laos and Burma, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the west by the Andaman Sea and Burma...
|
(BlythEdward Blyth was an English zoologist and pharmacist. He was one of the founders of Indian zoology....
, 1845) |
| S. a. biddulphi |
NW IndiaIndia, officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the west, and the Bay of Bengal...
and PakistanPakistan , officially the Islamic Republic of Pakistan, is a country located at the crossroads of South Asia, the Middle East, and Central Asia...
|
Scully, 1881 |
| S. a. willkonskii |
Palestine Palestine is a conventional name used, among others, to describe a geographic region between the Mediterranean Sea and the Jordan River, and various adjoining lands.As a geographical term, Palestine can also refer to 'ancient Palestine,' an area...
to N IranIran , officially the Islamic Republic of Iran is a country in Western Asia. The name Iran has been in use natively since the Sassanid period and came into international use from 1935, before which the country was known internationally as Persia...
and the CaucasusThe Caucasus or Caucas is a geopolitical region between at the border of Europe and Asia. It is home to the Caucasus Mountains, including Europe's highest mountain ....
|
(Menzbier, 1896) |
| S. a. mauritanica |
NW Africa Africa is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people in 61 territories, it accounts for about 14.8% of the...
from MoroccoMorocco, officially the Kingdom of Morocco, is a country located in North Africa with a population of nearly 32 million and an area just under . Its capital is Rabat, and its largest city is Casablanca. Morocco has a coast on the Atlantic Ocean that reaches past the Strait of Gibraltar into the...
to TunisiaTunisia , officially the Tunisian Republic , is a country located in North Africa. It is bordered by Algeria to the west and Libya to the southeast. Tunisia is located southwest of the island of Sicily and south of Sardinia. Its size is almost 165,000 km² with an estimated population of just...
and MauritaniaMauritania , officially the Islamic Republic of Mauritania, is a country in northwest Africa. It is bordered by the Atlantic Ocean on the west, by Senegal on the southwest, by Mali on the east and southeast, by Algeria on the northeast, and by the Morocco-controlled Western Sahara on the northwest...
|
(Witherby Henry Forbes Witherby M.B.E., F.Z.S., M.B.O.U. was a noted British ornithologist, author, publisher and founding editor of British Birds magazine....
, 1905) |
| S. a. sanctinicolai |
W Iran, NE IraqIraq , officially the Republic of Iraq , also known as Mesopotamia, is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert.Iraq shares borders with Jordan to the west, Syria...
|
(Zarudny, 1905) |
| S. a. ma |
NE China & KoreaKorea is a civilization and formerly unified nation currently divided into two states. Located on the Korean Peninsula, it borders China to the northwest, Russia to the northeast, and is separated from Japan to the east by the Korea Strait....
|
H. L. Clark Hubert Lyman Clark, Ph. D. was an American zoologist.Clark, son of William Smith Clark, was born at Amherst, Massachusetts, and educated at Amherst College and Johns Hopkins University....
, 1907 |
| S. a. harmsi |
TurkmenistanRepublic of Turkmenistan is a country in Central Asia. Until 1991, it was a constituent republic of the Soviet Union, the Turkmen Soviet Socialist Republic...
|
(Zarudny, 1911) |
| S. a. siberiae |
C RussiaRussia , officially known as both Russia and the Russian Federation , is a country in northern Eurasia . It is a semi-presidential republic, comprising 83 federal subjects...
from UralsThe Ural Mountains are a mountain range that runs roughly north-south through western Russia. They are usually considered the natural boundary between Europe and Asia....
to W Siberia |
Dementiev, 1933 |
| S. a. yamadae |
TaiwanTaiwan , also known as Formosa , is the largest island of the Republic of China in East Asia. Taiwan is located east of the Taiwan Strait, off the southeastern coast of mainland China...
|
Yamashina, 1936 |
Distribution and habitat
The Tawny Owl has a distribution stretching discontinuously across temperate Eurasia from Great Britain and the Iberian PeninsulaThe Iberian Peninsula, or Iberia, is located in the extreme southwest of Europe and includes modern-day Spain, Portugal, Andorra and Gibraltar and a very small area of France. It is the westernmost of the three major southern European peninsulas—the Iberian, Italian, and Balkan peninsulas...
eastwards to KoreaKorea is a civilization and formerly unified nation currently divided into two states. Located on the Korean Peninsula, it borders China to the northwest, Russia to the northeast, and is separated from Japan to the east by the Korea Strait....
, and south to Iran and the Himalayas. The subspecies S. a. mauritanica extends the range into northwest Africa. This essentially non-migratoryBird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. These however are usually irregular or in only one direction and are termed variously as nomadism, invasions,...
owl is absent from IrelandIreland is the third-largest island in Europe and the twentieth-largest island in the world. It lies to the north-west of continental Europe and is surrounded by hundreds of islands and islets. To the east of Ireland, separated by the Irish Sea, is the island of Great Britain...
, and only a rare vagrant to the BalearicThe Balearic Islands are an archipelago in the western Mediterranean Sea, near the eastern coast of the Iberian Peninsula....
and Canary IslandsThe Canary Islands are a Spanish archipelago which, in turn, forms one of the Spanish Autonomous Communities and an Outermost Region of the European Union. The archipelago is located just off the northwest coast of mainland Africa, 100 km west of the disputed border between Morocco and the...
.
This species is found in deciduousDeciduous means falling off at maturity or tending to fall off and is typically used in reference to trees or shrubs that lose their leaves seasonally and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
and mixed forests, and sometimes mature conifer plantations, preferring locations with access to water. Cemeteries, gardens and parks have allowed it to spread into urban areas, including central London[]London is the capital of England and the United Kingdom. It has been a major settlement for two millennia, and the history of London goes back to its founding by the Romans, when it was named Londinium. London's core, the ancient City of London, the 'square mile', retains its medieval boundaries...
. The Tawny Owl is mainly a lowland bird in the colder parts of its range, but breeds to 550 mThe metre or meter is the basic unit of length in the International System of Units . Historically, the metre was defined by the French Academy of Sciences as the length between two marks on a platinum-iridium bar, which was designed to represent one ten-millionth of the distance from the Equator...
(1,800 ftThe foot is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion...
) in ScotlandScotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
, 1,600 m (5,250 ft) in the AlpsThe Alps are one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east; through Italy, Switzerland, Liechtenstein and Germany; to France in the west....
, 2,350 m (7,700 ft) in TurkeyTurkey , known officially as the Republic of Turkey
, is a Eurasian country that stretches across the Anatolian peninsula in Western Asia and Thrace in the Balkan region of southeastern Europe...
, and up to 2,800 m (9,180 ft) in Burma.
The Tawny Owl has a geographical range of at least 10 million km² (3.8 million mi²) and a large population including an estimated 970,000–2,000,000 individuals in Europe alone. Population trends have not been quantified, but there is evidence of an overall increase. This owl is not believed to meet the IUCN Red ListThe IUCN Red List of Threatened Species , founded in 1948, is the world's most comprehensive inventory of the global conservation status of plant and animal species. The International Union for the Conservation of Nature and Natural Resources is the world's main authority on the conservation...
criterion of declining more than 30% in ten years or three generations and is therefore evaluated as Least ConcernLeast Concern is an IUCN category assigned to extant species or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, nor Near Threatened, nor Conservation Dependent...
. This species has expanded its range in BelgiumThe Kingdom of Belgium is a country in northwest Europe. It is a founding member of the European Union and hosts its headquarters, as well as those of other major international organizations, including NATO...
, the NetherlandsThe Netherlands is a country in Northwestern Europe, constituting the major portion of the Kingdom of the Netherlands. It is a parliamentary democratic constitutional monarchy. The Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east...
, NorwayNorway , officially the Kingdom of Norway, is a country in Northern Europe occupying the western portion of the Scandinavian Peninsula, as well as Jan Mayen and the Arctic archipelago of Svalbard under the Spitsbergen Treaty...
and UkraineUkraine is a country in Eastern Europe. It is bordered by Russia to the east; Belarus to the north; Poland, Slovakia, and Hungary to the west; Romania and Moldova to the southwest; and the Black Sea and Sea of Azov to the south. The city of Kiev is both the capital and the largest city of...
, and populations are stable or increasing in most European countries. Declines have occurred in FinlandFinland , officially the Republic of Finland
, is a Nordic country and democracy situated in the Fennoscandian region of northern Europe. It borders Sweden on the west, Russia on the east, and Norway on the north, while Estonia lies to its south across the Gulf of Finland...
, EstoniaEstonia , officially the Republic of Estonia , is a country in Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by the Russian Federation...
, ItalyItaly , officially the Italian Republic , is a country located on the Italian Peninsula in Southern Europe and on the two largest islands in the Mediterranean Sea, Sicily and Sardinia. Italy shares its northern, Alpine boundary with France, Switzerland, Austria and Slovenia...
and AlbaniaAlbania , officially the Republic of Albania , is a Mediterranean country in South Eastern Europe. It is bordered by Montenegro to the north, Kosovo to the northeast, Macedonia to the east and Greece to the south-east...
.
Breeding
Tawny Owls pair off from the age of one year, and stay together in a usually monogamousMonogamy is the state of having only one sexual partner at any one time. The word monogamy comes from the Greek word monos "μονός", which means one or alone, and the Greek word gamos "γάμος", which means marriage or union...
relationship for life. An established pair's territory is defended year-round and maintained with little, if any, boundary change from year to year. The pair sit in cover on a branch close to a tree trunk during the day, and usually roost separately from July to October. Roosting owls may be discovered and "mobbed" by small birds during the day, but they normally ignore the disturbance.
The Tawny Owl typically nests in a hole in a tree, but will also use old European MagpieThe European Magpie or Common Magpie is a resident breeding bird throughout Europe, much of Asia, and northwest Africa. It is one of several birds in the crow family named as magpies, and belongs to the Holarctic radiation of "monochrome" magpies.In Europe, "Magpie" is used by English speakers as...
nests, squirrelA squirrel is one of many small or medium-sized rodents in the family Sciuridae. In the English-speaking world, squirrel commonly refers to members of this family's genera Sciurus and Tamiasciurus, which are tree squirrels with large bushy tails, indigenous to Asia, the Americas and Europe....
dreys or holes in buildings, and readily takes to nest boxA nest box, nestbox or birdhouse) is a man-made box provided for animals to nest in. Nest boxes are most frequently utilized for wild and domesticated birds, but some mammal species may also use them.-Construction:...
es. It nests from February onwards in the south of its range, but rarely before mid-March in ScandinaviaScandinavia is a geographical region in northern Europe that includes, and is named after, the Scanian Province. It consists of the kingdoms of Norway, Sweden, and Denmark...
. The glossy white eggs are 48 x 39 mm (1.89 x 1.54 in) in size and weigh 39.0 g (1.4 oz) of which 7% is shell. The typical clutch of two or three eggs is incubated by the female alone for 30 days to hatching, and the altricialAltricial, meaning "requiring nourishment", refers to a pattern of growth and development in organisms which are incapable of moving around on their own soon after hatching or being born...
, downy chicks fledgeFledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of raising chicks to a fully grown state by the chick's parents...
in a further 35–39 days. The young usually leave the nest up to ten days before fledging, and hide on nearby branches.
This species is fearless in defence of its nest and young, and, like other StrixStrix is a genus of owls. They belong to the typical owl family Strigidae, one of the two generally accepted living families of owls, with the other being the barn-owls . Common names are earless owls or wood-owls though they are not the only owls without ear tufts, and "wood owl" is also used as a...
owls, strikes for the intruder's head with its sharp talons. Because its flight is silent, it may not be detected until it is too late to avoid the danger. Dogs, cats and humans may be assaulted, sometimes without provocation. Perhaps the best-known victim of the Tawny Owl's fierce attack was the renowned bird photographer Eric HoskingEric John Hosking OBE was an English photographer noted for his bird photography.Hosking was born in London. Although he pioneered several techniques for bird photography, during the first 10 years of his photography career, Hosking was not successful in being published...
, who lost an eye when struck by a bird he was attempting to photograph near its nest. He later called his autobiography An Eye for a Bird.
The parents care for young birds for two or three months after they fledge, but from August to November the juveniles disperse to find a territory of their own to occupy. If they fail to find a vacant territory, they usually starve. The juvenile survival rate is unknown, but the annual survival rate for adults is 76.8%. The typical lifespan is 5 years, but an age of over 18 years has been recorded for a wild Tawny Owl, and of over 27 years for a captive bird.
Predators of the Tawny Owl include large birds such as UralThe Ural Owl is a medium-large nocturnal owl of the genus Strix, with up to 15 subspecies found in Europe and northern Asia....
and Eagle Owls, Northern Goshawks and Common BuzzardThe Common Buzzard is a medium to large bird of prey, whose range covers most of Europe and extends into Asia. It is typically between 51-57 cm in length with a 110 to 130 cm wingspan, making it a medium-sized raptor. There are around 40,000 breeding pairs in Britain...
s. Pine MartenThe European Pine Marten , or Pineten, is an animal native to Northern Europe belonging to the mustelid family, which also includes mink, otter, badger, wolverine and weasel. It is about the size of a domestic cat. Its body is up to 53 cm in length , and its bushy tail can be 25 cm...
s may raid nests, especially where artificial nest boxes make the owls easy to find, and several instances have been recorded of Eurasian Jackdaws building nests on top of a brooding female Tawny Owl leading to the death of the adult and chicks. A DanishDenmark is a Scandinavian country in Northern Europe and the senior member of the Kingdom of Denmark. It is the southernmost of the Nordic countries; southwest of Sweden and south of Norway, and it is bordered to the south by Germany. Denmark borders both the Baltic and the North Sea...
study showed that predation by mammals, especially Red FoxThe red fox is a mammal of the order Carnivora. It has the widest range of any terrestrial carnivore, being native to Canada, Alaska, almost all of the contiguous United States, Europe, North Africa and almost all of Asia, including Japan. In Ireland and the UK, where there are no longer any other...
es, was a important cause of mortality in newly fledged young, with 36% dying between fledging and independence. The mortality risk increased with fledging date from 14% in April to more than 58% in June, and increasing predation of late broods may be an important selective agent for early breeding in this species.
Feeding
The Tawny Owl hunts almost entirely at night, watching from a perch before dropping or gliding silently down to its victim, but very occasionally it will hunt in daylight when it has young to feed. This species takes a wide range of preyIn ecology, predation describes a biological interaction where a predator feeds on its prey, . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of the prey...
, mainly woodland rodentRodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
s, but also other mammalMammals are a class of vertebrate animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain.Mammals are divided into three main...
s up to the size of a young rabbitRabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world. There are seven different genera in the family classified as rabbits, including the European rabbit , Cottontail rabbit , and the Amami rabbit...
, and birdBirds are winged, bipedal, endothermic , vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the Bee Hummingbird to the ...
s, earthwormEarthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s and beetleBeetles are the group of insects with the largest number of known species. They are classified in the order Coleoptera , which contains more described species than in any other order in the animal kingdom, constituting about 25% of all known life-forms...
s. In urban areas, birds make up a larger proportion of the diet, and species as unlikely as MallardThe Mallard , probably the best-known and most recognizable of all ducks, is a dabbling duck which breeds throughout the temperate and sub-tropical areas of North America, Europe, Asia, Africa, New Zealand , and Australia...
and KittiwakeThe Black-legged Kittiwake, Rissa tridactyla, is a seabird species in the gull family Laridae.This species was first described by Linnaeus in his Systema naturae in 1758 as Larus tridactylus....
have been killed and eaten.
Prey is typically swallowed whole, with indigestible parts regurgitated as pelletsA pellet, in ornithology, is the mass of undigested parts of a bird's food that some bird species occasionally regurgitate. The contents of a bird's pellet depend on its diet, but can include the exoskeletons of insects, indigestible plant matter, bones, fur, feathers, bills, claws, and teeth...
. These are medium-sized and grey, consisting mainly of rodent fur and often with bones protruding, and are found in groups under trees used for roosting or nesting.
Less powerful woodland owls such as the Little OwlThe Little Owl is a bird which is resident in much of the temperate and warmer parts of Europe, Asia east to Korea, and north Africa. It is not native to Great Britain, but was first introduced in 1842, and is now naturalised there...
and the Long-eared OwlThe Long-eared Owl - Asio otus is a species of owl which breeds in Europe, Asia, and North America. This species is a part of the larger grouping of owls known as typical owls, family Strigidae, which contains most species of owl...
cannot usually co-exist with the stronger Tawny, which may take them as food items, and are found in different habitats. Similarly, where the Tawny Owl has moved into built-up areas, it tends to displace Barn OwlThe Barn Owl is the most widely distributed species of owl, and one of the most widespread of all birds. It is also referred to as Common Barn Owl, to distinguish it from other species in the barn-owl family Tytonidae. These form one of the two living main lineages groups of owls, the other being...
s from their traditional nesting sites in buildings.
In culture
The Tawny Owl, like its relatives, has often been seen as an omen of bad luck, and William ShakespeareWilliam Shakespeare was an English poet and playwright, widely regarded as the greatest writer in the English language and the world's preeminent dramatist. He is often called England's national poet and the "Bard of Avon"...
used it as such in Julius CaesarJulius Caesar is a tragedy by William Shakespeare, believed to have been written in 1599. It portrays the conspiracy against the Roman dictator of the same name, his assassination and its aftermath...
(Act 1 Scene 3) "And yesterday the bird of night did sit/ Even at noon-day upon the market-place/ Hooting and shrieking." Even John RuskinJohn Ruskin was an English art critic and social thinker, also remembered as an author, poet and artist. His essays on art and architecture were extremely influential in the Victorian and Edwardian eras....
is quoted as saying "Whatever wise people may say of them, I at least have found the owl's cry always prophetic of mischief to me".
Wordsworth described the technique for calling an owl in his poem About a boy.
And there, with fingers interwoven, both hands
Pressed closely palm to palm and to his mouth
Uplifted, he, as through an instrument,
Blew mimic hootings to the silent owls,
That they might answer him.--And they would shout
Across the watery vale, and shout again,
Responsive to his call,--with quivering peals,
And long halloos, and screams, and echoes loud
Redoubled and redoubled; concourse wild
Of jocund din!
Owls were associated with BlodeuweddIn Welsh mythology, Blodeuwedd or Blodeuedd, , is a woman made from the flowers of broom, meadowsweet and the oak by Math fab Mathonwy and Gwydion to be the wife of Lleu Llaw Gyffes...
, who betrayed Lleu Llaw GyffesLleu Llaw Gyffes is a figure of Welsh mythology. He appears in the Fourth Branch of the Mabinogi, the tale of Math fab Mathonwy...
in the tale of Math son of Mathonwy from the ancient WelshWales is a country that is part of the United Kingdom, bordered by England to its east, and the Atlantic Ocean and Irish Sea to its west. It is also an elective region of the European Union...
MabinogionThe Mabinogion is the title given to a collection of eleven prose stories collated from medieval Welsh manuscripts. The tales draw on pre-Christian Celtic mythology, international folktale motifs, and early medieval historical traditions...
, and the call of an owl amongst the houses of a village was believed in Wales to signify that a girl had lost her virginity.
External links