Owls are birds from the order Strigiformes, which includes about 200 species of mostly solitary and nocturnal birds of prey typified by an upright stance, a large, broad head, binocular vision, binaural hearing, sharp talons, and feathers adapted for silent flight. Exceptions include the diurnal northern hawk-owl and the gregarious burrowing owl.
|Eastern barn owl |
(Tyto javanica stertens)
Mangaon, Maharashtra, India
|Range of the owl, all species.|
Strigidae sensu Sibley & Ahlquist
Owls possess large, forward-facing eyes and ear-holes, a hawk-like beak, a flat face, and usually a conspicuous circle of feathers, a facial disc, around each eye. The feathers making up this disc can be adjusted to sharply focus sounds from varying distances onto the owls' asymmetrically placed ear cavities. Most birds of prey have eyes on the sides of their heads, but the stereoscopic nature of the owl's forward-facing eyes permits the greater sense of depth perception necessary for low-light hunting. Although owls have binocular vision, their large eyes are fixed in their sockets—as are those of most other birds—so they must turn their entire heads to change views. As owls are farsighted, they are unable to clearly see anything within a few centimeters of their eyes. Caught prey can be felt by owls with the use of filoplumes—hairlike feathers on the beak and feet that act as "feelers". Their far vision, particularly in low light, is exceptionally good.
Owls can rotate their heads and necks as much as 270°. Owls have 14 neck vertebrae compared to seven in humans, which makes their necks more flexible. They also have adaptations to their circulatory systems, permitting rotation without cutting off blood to the brain: the foramina in their vertebrae through which the vertebral arteries pass are about 10 times the diameter of the artery, instead of about the same size as the artery as in humans; the vertebral arteries enter the cervical vertebrae higher than in other birds, giving the vessels some slack, and the carotid arteries unite in a very large anastomosis or junction, the largest of any bird's, preventing blood supply from being cut off while they rotate their necks. Other anastomoses between the carotid and vertebral arteries support this effect.
The smallest owl—weighing as little as 31 g (1 oz) and measuring some 13.5 cm (5 in)—is the elf owl (Micrathene whitneyi). Around the same diminutive length, although slightly heavier, are the lesser known long-whiskered owlet (Xenoglaux loweryi) and Tamaulipas pygmy owl (Glaucidium sanchezi). The largest owls are two similarly sized eagle owls; the Eurasian eagle-owl (Bubo bubo) and Blakiston's fish owl (Bubo blakistoni). The largest females of these species are 71 cm (28 in) long, have 54 cm (21 in) long wings, and weigh 4.2 kg (9.3 lb).
Different species of owls produce different sounds; this distribution of calls aids owls in finding mates or announcing their presence to potential competitors, and also aids ornithologists and birders in locating these birds and distinguishing species. As noted above, their facial discs help owls to funnel the sound of prey to their ears. In many species, these discs are placed asymmetrically, for better directional location.
Owl plumage is generally cryptic, although several species have facial and head markings, including face masks, ear tufts, and brightly coloured irises. These markings are generally more common in species inhabiting open habitats, and are thought to be used in signaling with other owls in low-light conditions.
Sexual dimorphism is a physical difference between males and females of a species. Reverse sexual dimorphism, when females are larger than males, has been observed across multiple owl species. The degree of size dimorphism varies across multiple populations and species, and is measured through various traits, such as wing span and body mass. Overall, female owls tend to be slightly larger than males. The exact explanation for this development in owls is unknown. However, several theories explain the development of sexual dimorphism in owls.
One theory suggests that selection has led males to be smaller because it allows them to be efficient foragers. The ability to obtain more food is advantageous during breeding season. In some species, female owls stay at their nest with their eggs while it is the responsibility of the male to bring back food to the nest. However, if food is scarce, the male first feeds himself before feeding the female. Small birds, which are agile, are an important source of food for owls. Male burrowing owls have been observed to have longer wing chords than females, despite being smaller than females. Furthermore, owls have been observed to be roughly the same size as their prey. This has also been observed in other predatory birds, which suggests that owls with smaller bodies and long wing chords have been selected for because of the increased agility and speed that allows them to catch their prey.
Another popular theory suggests that females have not been selected to be smaller like male owls because of their sexual roles. In many species, female owls may not leave the nest. Therefore, females may have a larger mass to allow them to go for a longer period of time without starving. For example, one hypothesized sexual role is that larger females are more capable of dismembering prey and feeding it to their young, hence female owls are larger than their male counterparts.
A different theory suggests that the size difference between male and females is due to sexual selection: since large females can choose their mate and may violently reject a male's sexual advances, smaller male owls that have the ability to escape unreceptive females are more likely to have been selected.
All owls are carnivorous birds of prey and live mainly on a diet of insects and small rodents such as mice, rats, and hares. Some owls are also specifically adapted to hunt fish. They are very adept in hunting in their respective environments. Since owls can be found in nearly all parts of the world and across a multitude of ecosystems, their hunting skills and characteristics vary slightly from species to species, though most characteristics are shared among all species.
Most owls share an innate ability to fly almost silently and also more slowly in comparison to other birds of prey. Most owls live a mainly nocturnal lifestyle and being able to fly without making any noise gives them a strong advantage over their prey that are listening for the slightest sound in the night. A silent, slow flight is not as necessary for diurnal and crepuscular owls given that prey can usually see an owl approaching. While the morphological and biological mechanisms of this silent flight are more or less unknown, the structure of the feather has been heavily studied and accredited to a large portion of why they have this ability. Owls’ feathers are generally larger than the average birds’ feathers, have fewer radiates, longer pennulum, and achieve smooth edges with different rachis structures. Serrated edges along the owl's remiges bring the flapping of the wing down to a nearly silent mechanism. The serrations are more likely reducing aerodynamic disturbances, rather than simply reducing noise. The surface of the flight feathers is covered with a velvety structure that absorbs the sound of the wing moving. These unique structures reduce noise frequencies above 2 kHz, making the sound level emitted drop below the typical hearing spectrum of the owl's usual prey and also within the owl's own best hearing range. This optimizes the owl's ability to silently fly to capture prey without the prey hearing the owl first as it flies in. It also allows the owl to monitor the sound output from its flight pattern.
The feather adaption that allows silent flight means that barn owl feathers are not waterproof. To retain the softness and silent flight, the barn owl cannot use the preen oil or powder dust that other species use for waterproofing. In wet weather, they cannot hunt and this may be disastrous during the breeding season. Barn owls are frequently found drowned in cattle drinking troughs, since they land to drink and bathe, but are unable to climb out. Owls can struggle to keep warm, because of their lack of waterproofing, so large numbers of downy feathers help them to retain body heat.
Eyesight is a particular characteristic of the owl that aids in nocturnal prey capture. Owls are part of a small group of birds that live nocturnally, but do not use echolocation to guide them in flight in low-light situations. Owls are known for their disproportionally large eyes in comparison to their skulls. An apparent consequence of the evolution of an absolutely large eye in a relatively small skull is that the eye of the owl has become tubular in shape. This shape is found in other so-called nocturnal eyes, such as the eyes of strepsirrhine primates and bathypelagic fishes. Since the eyes are fixed into these sclerotic tubes, they are unable to move the eyes in any direction. Instead of moving their eyes, owls swivel their heads to view their surroundings. Owls' heads are capable of swiveling through an angle of roughly 270°, easily enabling them to see behind them without relocating the torso. This ability keeps bodily movement at a minimum, thus reduces the amount of sound the owl makes as it waits for its prey. Owls are regarded as having the most frontally placed eyes among all avian groups, which gives them some of the largest binocular fields of vision. However, owls are farsighted and cannot focus on objects within a few centimeters of their eyes. These mechanisms are only able to function due to the large-sized retinal image. Thus, the primary nocturnal function in the vision of the owl is due to its large posterior nodal distance; retinal image brightness is only maximized to the owl within secondary neural functions. These attributes of the owl cause its nocturnal eyesight to be far superior to that of its average prey.
Owls exhibit specialized hearing functions and ear shapes that also aid in hunting. They are noted for asymmetrical ear placements on the skull in some genera. Owls can have either internal or external ears, both of which are asymmetrical. Asymmetry has not been reported to extend to the middle or internal ear of the owl. Asymmetrical ear placement on the skull allows the owl to pinpoint the location of its prey. This is especially true for strictly nocturnal species such as the barn owls Tyto or Tengmalm's owl. With ears set at different places on its skull, an owl is able to determine the direction from which the sound is coming by the minute difference in time that it takes for the sound waves to penetrate the left and right ears. The owl turns its head until the sound reaches both ears at the same time, at which point it is directly facing the source of the sound. This time difference between ears is a matter of about 0.00003 seconds, or 30 millionths of a second. Behind the ear openings are modified, dense feathers, densely packed to form a facial ruff, which creates an anterior-facing, concave wall that cups the sound into the ear structure. This facial ruff is poorly defined in some species, and prominent, nearly encircling the face, in other species. The facial disk also acts to direct sound into the ears, and a downward-facing, sharply triangular beak minimizes sound reflection away from the face. The shape of the facial disk is adjustable at will to focus sounds more effectively.
The prominences above a great horned owl's head are commonly mistaken as its ears. This is not the case; they are merely feather tufts. The ears are on the sides of the head in the usual location (in two different locations as described above).
While the auditory and visual capabilities of the owl allow it to locate and pursue its prey, the talons and beak of the owl do the final work. The owl kills its prey using these talons to crush the skull and knead the body. The crushing power of an owl's talons varies according to prey size and type, and by the size of the owl. The burrowing owl (Athene cunicularia), a small, partly insectivorous owl, has a release force of only 5 N. The larger barn owl (Tyto alba) needs a force of 30 N to release its prey, and one of the largest owls, the great horned owl (Bubo virginianus) needs a force over 130 N to release prey in its talons. An owl's talons, like those of most birds of prey, can seem massive in comparison to the body size outside of flight. The masked owl has some of the proportionally longest talons of any bird of prey; they appear enormous in comparison to the body when fully extended to grasp prey. An owl's claws are sharp and curved. The family Tytonidae has inner and central toes of about equal length, while the family Strigidae has an inner toe that is distinctly shorter than the central one. These different morphologies allow efficiency in capturing prey specific to the different environments they inhabit.
The beak of the owl is short, curved, and downward-facing, and typically hooked at the tip for gripping and tearing its prey. Once prey is captured, the scissor motion of the top and lower bill is used to tear the tissue and kill. The sharp lower edge of the upper bill works in coordination with the sharp upper edge of the lower bill to deliver this motion. The downward-facing beak allows the owl's field of vision to be clear, as well as directing sound into the ears without deflecting sound waves away from the face.
The coloration of the owl's plumage plays a key role in its ability to sit still and blend into the environment, making it nearly invisible to prey. Owls tend to mimic the colorations and sometimes even the texture patterns of their surroundings, the common barn owl being an exception. Nyctea scandiaca, or the snowy owl, appears nearly bleach-white in color with a few flecks of black, mimicking their snowy surroundings perfectly. Likewise, the mottled wood-owl (Strix ocellata) displays shades of brown, tan, and black, making the owl nearly invisible in the surrounding trees, especially from behind. Usually, the only tell-tale sign of a perched owl is its vocalizations or its vividly colored eyes.
Most owls are nocturnal, actively hunting their prey in darkness. Several types of owls, however, are crepuscular—active during the twilight hours of dawn and dusk; one example is the pygmy owl (Glaucidium). A few owls are active during the day, also; examples are the burrowing owl (Speotyto cunicularia) and the short-eared owl (Asio flammeus).
Much of the owls' hunting strategy depends on stealth and surprise. Owls have at least two adaptations that aid them in achieving stealth. First, the dull coloration of their feathers can render them almost invisible under certain conditions. Secondly, serrated edges on the leading edge of owls' remiges muffle an owl's wing beats, allowing an owl's flight to be practically silent. Some fish-eating owls, for which silence has no evolutionary advantage, lack this adaptation.
An owl's sharp beak and powerful talons allow it to kill its prey before swallowing it whole (if it is not too big). Scientists studying the diets of owls are helped by their habit of regurgitating the indigestible parts of their prey (such as bones, scales, and fur) in the form of pellets. These "owl pellets" are plentiful and easy to interpret, and are often sold by companies to schools for dissection by students as a lesson in biology and ecology.
Owl eggs typically have a white colour and an almost spherical shape, and range in number from a few to a dozen, depending on species and the particular season; for most, three or four is the more common number. In at least one species, female owls do not mate with the same male for a lifetime. Female burrowing owls commonly travel and find other mates, while the male stays in his territory and mates with other females.
The systematic placement of owls is disputed. For example, the Sibley–Ahlquist taxonomy of birds finds that, based on DNA-DNA hybridization, owls are more closely related to the nightjars and their allies (Caprimulgiformes) than to the diurnal predators in the order Falconiformes; consequently, the Caprimulgiformes are placed in the Strigiformes, and the owls in general become a family, the Strigidae. A recent study indicates that the drastic rearrangement of the genome of the accipitrids may have obscured any close relationship of theirs with groups such as the owls. In any case, the relationships of the Caprimulgiformes, the owls, the falcons, and the accipitrid raptors are not resolved to satisfaction; currently, a trend to consider each group (with the possible exception of the accipitrids) as a distinct order is increasing.
Some 220 to 225 extant species of owls are known, subdivided into two families: 1. Typical owls or True owl family (Strigidae) and 2. barn-owls family (Tytonidae). Some entirely extinct families have also been erected based on fossil remains; these differ much from modern owls in being less specialized or specialized in a very different way (such as the terrestrial Sophiornithidae). The Paleocene genera Berruornis and Ogygoptynx show that owls were already present as a distinct lineage some 60–57 million years ago (Mya), hence, possibly also some 5 million years earlier, at the extinction of the nonavian dinosaurs. This makes them one of the oldest known groups of non-Galloanserae landbirds. The supposed "Cretaceous owls" Bradycneme and Heptasteornis are apparently nonavialan maniraptors.
During the Paleogene, the Strigiformes radiated into ecological niches now mostly filled by other groups of birds. The owls as known today, though, evolved their characteristic morphology and adaptations during that time, too. By the early Neogene, the other lineages had been displaced by other bird orders, leaving only barn-owls and typical owls. The latter at that time were usually a fairly generic type of (probably earless) owls similar to today's North American spotted owl or the European tawny owl; the diversity in size and ecology found in typical owls today developed only subsequently.
Around the Paleogene-Neogene boundary (some 25 Mya), barn-owls were the dominant group of owls in southern Europe and adjacent Asia at least; the distribution of fossil and present-day owl lineages indicates that their decline is contemporary with the evolution of the different major lineages of typical owls, which for the most part seems to have taken place in Eurasia. In the Americas, rather an expansion of immigrant lineages of ancestral typical owls occurred.
The supposed fossil herons "Ardea" perplexa (Middle Miocene of Sansan, France) and "Ardea" lignitum (Late Pliocene of Germany) were more probably owls; the latter was apparently close to the modern genus Bubo. Judging from this, the Late Miocene remains from France described as "Ardea" aureliensis should also be restudied. The Messelasturidae, some of which were initially believed to be basal Strigiformes, are now generally accepted to be diurnal birds of prey showing some convergent evolution towards owls. The taxa often united under Strigogyps were formerly placed in part with the owls, specifically the Sophiornithidae; they appear to be Ameghinornithidae instead.
Unresolved and basal forms (all fossil)
Among the Kikuyu of Kenya, it was believed that owls were harbingers of death. If one saw an owl or heard its hoot, someone was going to die. In general, owls are viewed as harbingers of bad luck, ill health, or death. The belief is widespread even today.
In Mongolia the owl is regarded as a benign omen. In one story, Genghis Khan was hiding from enemies in a small coppice when an owl roosted in the tree above him, which caused his pursuers to think no man could be hidden there.
In modern Japan, owls are regarded as lucky and are carried in the form of a talisman or charm.
The modern West generally associates owls with wisdom and vigilance. This link goes back at least as far as Ancient Greece, where Athens, noted for art and scholarship, and Athena, Athens' patron goddess and the goddess of wisdom, had the owl as a symbol. Marija Gimbutas traces veneration of the owl as a goddess, among other birds, to the culture of Old Europe, long pre-dating Indo-European cultures.
T. F. Thiselton-Dyer in his Folk-lore of Shakespeare says that "from the earliest period it has been considered a bird of ill-omen," and Pliny tells us how, on one occasion, even Rome itself underwent a lustration, because one of them strayed into the Capitol. He represents it also as a funereal bird, a monster of the night, the very abomination of human kind. Virgil describes its death-howl from the top of the temple by night, a circumstance introduced as a precursor of Dido's death. Ovid, too, constantly speaks of this bird's presence as an evil omen; and indeed the same notions respecting it may be found among the writings of most of the ancient poets." A list of "omens drear" in John Keats' Hyperion includes the "gloom-bird's hated screech." Pliny the Elder reports that owl's eggs were commonly used as a hangover cure.
People often allude to the reputation of owls as bearers of supernatural danger when they tell misbehaving children, "the owls will get you", and in most Native American folklore, owls are a symbol of death. For example:
Encouraging natural predators to control rodent population is a natural form of pest control, along with excluding food sources for rodents. Placing a nest box for owls on a property can help control rodent populations (one family of hungry barn owls can consume more than 3,000 rodents in a nesting season) while maintaining the naturally balanced food chain.
Although humans and owls frequently live together in harmony, there have been incidents when owls have attacked humans. For example, in January 2013, a man from Inverness, Scotland suffered heavy bleeding and went into shock after being attacked by an owl, which was likely a 50-cm tall eagle owl. The photographer Eric Hosking lost his left eye after attempting to photograph a tawny owl, which inspired the title of his 1970 autobiography, An Eye for a Bird.
All owls are listed in Appendix II of the international CITES treaty (the Convention on Illegal Trade in Endangered Species of Wild Fauna and Flora). Although owls have long been hunted, a 2008 news story from Malaysia indicates that the magnitude of owl poaching may be on the rise. In November 2008, TRAFFIC reported the seizure of 900 plucked and "oven-ready" owls in Peninsular Malaysia. Said Chris Shepherd, Senior Programme Officer for TRAFFIC's Southeast Asia office, "This is the first time we know of where 'ready-prepared' owls have been seized in Malaysia, and it may mark the start of a new trend in wild meat from the region. We will be monitoring developments closely." TRAFFIC commended the Department of Wildlife and National Parks in Malaysia for the raid that exposed the huge haul of owls. Included in the seizure were dead and plucked barn owls, spotted wood owls, crested serpent eagles, barred eagles, and brown wood owls, as well as 7,000 live lizards.
Barn owls (family Tytonidae) are one of the two families of owls, the other being the true owls or typical owls, Strigidae. They are medium to large owls with large heads and characteristic heart-shaped faces. They have long, strong legs with powerful talons. They also differ from the Strigidae in structural details relating in particular to the sternum and feet.The barn owls are a wide-ranging family, although they are absent from northern North America, Saharan Africa, and large areas of Asia. They live in a wide range of habitats from deserts to forests, and from temperate latitudes to the tropics. The majority of the twenty living species of barn-owls are poorly known. Some, like the red owl, have barely been seen or studied since their discovery, in contrast to the common barn-owl, which is one of the best known owl species in the world. However, some subspecies of the common barn-owl possibly deserve to be separate species, but are very poorly known.
Five species of barn owl are threatened, and some island species have gone extinct during the Holocene or earlier (e.g. Tyto pollens, known from the fossil record of Andros Island in the Bahamas, and possibly the basis for the mythical Chickcharnie). The barn owls are mostly nocturnal, and generally non-migratory, living in pairs or singly.Barn owl
The barn owl (Tyto alba) is the most widely distributed species of owl and one of the most widespread of all birds. It is also referred to as the common barn owl, to distinguish it from other species in its family, Tytonidae, which forms one of the two main lineages of living owls, the other being the typical owls (Strigidae). The barn owl is found almost everywhere in the world except polar and desert regions, in Asia north of the Himalaya, most of Indonesia, and some Pacific islands.Phylogenetic evidence shows that there are at least three major lineages of barn owl, one in Europe, western Asia and Africa, one in southeast Asia and Australasia, and one in the Americas, and some highly divergent taxa on islands. Accordingly, some authorities split the group into the western barn owl for the group in Europe, western Asia and Africa, the American barn owl for the group in the Americas, and the eastern barn owl for the group in southeast Asia and Australasia. Some taxonomic authorities further split the group, recognising up to five species, and further research needs to be done to clarify the position. There is a considerable variation between the sizes and colour of the approximately 28 subspecies but most are between 33 and 39 cm (13 and 15 in) in length with wingspans ranging from 80 to 95 cm (31 to 37 in). The plumage on head and back is a mottled shade of grey or brown, the underparts vary from white to brown and are sometimes speckled with dark markings. The face is characteristically heart-shaped and is white in most subspecies. This owl does not hoot, but utters an eerie, drawn-out shriek.
The barn owl is nocturnal over most of its range, but in Britain and some Pacific islands, it also hunts by day. Barn owls specialise in hunting animals on the ground and nearly all of their food consists of small mammals which they locate by sound, their hearing being very acute. They usually mate for life unless one of the pair is killed, when a new pair bond may be formed. Breeding takes place at varying times of year according to locality, with a clutch, averaging about four eggs, being laid in a nest in a hollow tree, old building or fissure in a cliff. The female does all the incubation, and she and the young chicks are reliant on the male for food. When large numbers of small prey are readily available, barn owl populations can expand rapidly, and globally the bird is considered to be of least conservation concern. Some subspecies with restricted ranges are more threatened.Barred owl
The barred owl (Strix varia), also known as northern barred owl or hoot owl, is a true owl native to eastern North America. Adults are large, and are brown to grey with barring on the chest. Barred owls have expanded their range to the west coast of North America, where they are considered invasive. Mature forests are their preferred habitat, but they are also found in open woodland areas. Their diet consists mainly of small mammals, but they are also known to prey upon other small animals such as birds, reptiles, and amphibians.Burrowing owl
The burrowing owl (Athene cunicularia) is a small, long-legged owl found throughout open landscapes of North and South America. Burrowing owls can be found in grasslands, rangelands, agricultural areas, deserts, or any other open dry area with low vegetation. They nest and roost in burrows, such as those excavated by prairie dogs (Cynomys spp.). Unlike most owls, burrowing owls are often active during the day, although they tend to avoid the midday heat. Like many other kinds of owls, though, burrowing owls do most of their hunting from dusk until dawn, when they can use their night vision and hearing to their advantage. Living in open grasslands as opposed to forests, the burrowing owl has developed longer legs that enable it to sprint, as well as fly, when hunting.Eurasian eagle-owl
The Eurasian eagle-owl (Bubo bubo) is a species of eagle-owl that resides in much of Eurasia. It is also called the European eagle-owl and in Europe, it is occasionally abbreviated to just eagle-owl. It is one of the largest species of owl, and females can grow to a total length of 75 cm (30 in), with a wingspan of 188 cm (6 ft 2 in), males being slightly smaller. This bird has distinctive ear tufts, with upper parts that are mottled with darker blackish colouring and tawny. The wings and tail are barred. The underparts are a variably hued buff, streaked with darker colour. The facial disc is not very visible and the orange eyes are distinctive.
The Eurasian eagle-owl is one of the largest living species of owl as well as one of the most widely distributed. The Eurasian eagle-owl is found in many habitats but is mostly a bird of mountain regions, coniferous forests, steppes and other relatively remote places. It is a mostly nocturnal predator, hunting for a range of different prey species, predominantly small mammals but also birds of varying sizes, reptiles, amphibians, fish, large insects and other assorted invertebrates. It typically breeds on cliff ledges, in gullies, among rocks or in other concealed locations. The nest is a scrape in which averages of two eggs are laid at intervals. These hatch at different times. The female incubates the eggs and broods the young, and the male provides food for her and, when they hatch, for the nestlings as well. Continuing parental care for the young is provided by both adults for about five months. There are at least a dozen subspecies of Eurasian eagle-owl.With a total range in Europe and Asia of about 32 million square kilometres (12 million square miles) and a total population estimated to be between 250 thousand and 2.5 million, the IUCN lists the bird's conservation status as being of "least concern". The vast majority of eagle-owls live in mainland Europe, Russia and Central Asia, and an estimated number of between 12 and 40 pairs are thought to reside in the United Kingdom as of 2016, a number which may be on the rise. Tame eagle-owls have occasionally been used in pest control because of their size to deter large birds such as gulls from nesting.Great horned owl
The great horned owl (Bubo virginianus), also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air") or the hoot owl, is a large owl native to the Americas. It is an extremely adaptable bird with a vast range and is the most widely distributed true owl in the Americas. Its primary diet is rabbits and hares, rats and mice, and voles, although it freely hunts any animal it can overtake, including rodents and other small mammals, larger mid-sized mammals, birds, reptiles, amphibians, and invertebrates. In ornithological study, the great horned owl is often compared to the Eurasian eagle-owl (Bubo bubo), a closely related species, which despite the latter's notably larger size, occupies the same ecological niche in Eurasia, and the red-tailed hawk (Buteo jamaicensis), with which it often shares similar habitat, prey, and nesting habits by day, thus is something of a diurnal ecological equivalent. The great horned owl is one of the earliest nesting birds in North America, often laying eggs weeks or even months before other raptorial birds.Little owl
The little owl (Athene noctua) is a bird that inhabits much of the temperate and warmer parts of Europe, Asia east to Korea, and north Africa. It was introduced into Britain at the end of the nineteenth century and into the South Island of New Zealand in the early twentieth century.
This owl is a member of the typical or true owl family, Strigidae, which contains most species of owl, the other grouping being the barn owls, Tytonidae. It is a small, cryptically coloured, mainly nocturnal species and is found in a range of habitats including farmland, woodland fringes, steppes and semi-deserts. It feeds on insects, earthworms, other invertebrates and small vertebrates. Males hold territories which they defend against intruders. This owl is a cavity nester and a clutch of about four eggs is laid in spring. The female does the incubation and the male brings food to the nest, first for the female and later for the newly hatched young. As the chicks grow, both parents hunt and bring them food, and the chicks leave the nest at about seven weeks of age.
Being a common species with a wide range and large total population, the International Union for Conservation of Nature has assessed its conservation status as "least concern".Long-eared owl
The long-eared owl (Asio otus), also known as the northern long-eared owl, 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. The other grouping of owls are the barn owls, family Tytonidae.
The scientific name is from Latin. The genus name Asio is a type of eared owl, and otus also refers to a small eared owl.O RLY?
O RLY? is an Internet phenomenon, typically presented as an image macro featuring a snowy owl. The phrase "O RLY?", an abbreviated form of "Oh, really?", is popularly used in Internet forums in a sarcastic manner, often in response to an obvious, predictable, or blatantly false statement. Similar owl image macros followed the original to present different views, including images with the phrases "YA RLY" (Yeah, really.), "NO WAI!!" (No way!)., and NO RLY. (Not really.)Owl (Marvel Comics)
The Owl (Leland Owlsley) is a fictional supervillain appearing in American comic books published by Marvel Comics. The character is depicted usually as an enemy of the superheroes Daredevil, Spider-Man and Black Cat. Created by writer Stan Lee and artist Joe Orlando, the character first appeared in Daredevil #3 (August 1964).
The character has appeared in numerous media adaptations, including the Marvel Cinematic Universe Netflix television series Daredevil in the first season, in which he was played by Bob Gunton.Owl City
Owl City is an American electronica project created in 2007 in Owatonna, Minnesota; it is one of several projects by singer, songwriter and multi-instrumentalist Adam Young. Young created the project while experimenting with music in his parents' basement. Owl City developed a following on the social networking site MySpace, like many musicians who achieved success in the late 2000s, before signing with Universal Republic Records, now Republic Records, in 2008.
After two independent releases, Owl City gained mainstream popularity with the 2009 major label debut album Ocean Eyes, which includes the six-time Platinum single "Fireflies". The album was certified Platinum in the United States in April 2010.
In June 2011, Owl City released its third studio album, All Things Bright and Beautiful, which was followed by The Midsummer Station in August 2012. Owl City has recorded songs for several animated films, including Legend of the Guardians: The Owls of Ga'Hoole, Wreck-It Ralph, The Croods and The Smurfs 2. Owl City also has released several charting singles, most notably "Good Time" and "Fireflies".Qubo
Qubo ( KEW-boh; stylized as qubo) is an American free-to-air children's entertainment programming service. Qubo consists of a 24-hour television network, alternately known as Qubo Channel (which is available as a digital terrestrial television on owned-and-operated stations and some affiliates of corporate sister Ion Television, and on some pay television providers), a video on demand service, and the branding of a weekly programming block on Ion Television under the name "Qubo Kids Corner".Sheffield Wednesday F.C.
Sheffield Wednesday Football Club is a professional association football club based in Sheffield, England. The team competes in the Championship, the second tier of the English football league system. Formed in 1867 as an offshoot of The Wednesday Cricket Club (itself formed in 1820), they went by the name of the Wednesday Football Club until changing to their current name in 1929.
Wednesday is one of the oldest football clubs in the world of any code, and the third-oldest professional association football club in England. In 1868 its team won the Cromwell Cup, only the second tournament of its kind. They were founding members and inaugural champions of the Football Alliance in 1889, before joining The Football League three years later. In 1992 they became founder members of the Premier League. The team has spent most of its league history in English football's top flight, but they have not played at that level since being relegated in 2000.
The Owls, as they are nicknamed, have won four league titles, three FA Cups, one League Cup and one FA Community Shield. Wednesday have also competed in UEFA cup competitions on four occasions, reaching the quarter-finals of the Inter-Cities Fairs Cup in 1963. In 1991 they defeated Manchester United 1-0 in the Football League Cup Final as a tier 2 team. As of 2019 they remain the last team outside the top flight to win one of English football's major trophiesIn the 19th century they played their matches at several stadiums around central Sheffield, most notabally Olive Grove and Bramall Lane. Since 1899 the club has played all its home matches at Hillsborough stadium, a near-40,000 capacity stadium in the north-west Sheffield suburb of Owlerton.Short-eared owl
The short-eared owl (Asio flammeus) is a species of typical owl (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 may not be visible. Asio flammeus will display its tufts when in a defensive pose, although its very short tufts are usually not visible. The short-eared owl is found in open country and grasslands. The scientific name is from Latin. The genus name Asio is a type of eared owl, and flammeus means "flame-coloured".Snowy owl
The snowy owl (Bubo scandiacus) is a large, white owl of the true owl family. Snowy owls are native to Arctic regions in North America and Eurasia. Males are almost all white, while females have more flecks of black plumage. Juvenile snowy owls have black feathers until they turn white. The snowy owl is a ground nester that primarily hunts rodents and waterfowl, and opportunistically eats carrion. Most owls sleep during the day and hunt at night, but the snowy owl is active during the day, especially in the summertime.Super Bowl
The Super Bowl is the annual championship game of the National Football League played annually between the champions of the National Football Conference and the American Football Conference . The game is the culmination of a regular season that begins in the late summer of the previous calendar year. Normally, Roman numerals are used to identify each game, rather than the year in which it is held. For example, Super Bowl I was played on January 15, 1967, following the 1966 regular season. The sole exception to this naming convention tradition occurred with Super Bowl 50, which was played on February 7, 2016, following the 2015 regular season, and the following year, the nomenclature returned to Roman numerals for Super Bowl LI, following the 2016 regular season. The upcoming Super Bowl is Super Bowl LIV, scheduled for February 2, 2020, following the 2019 regular season.
The game was created as a part of the merger agreement between the NFL and its then-rival, the American Football League (AFL). It was agreed that the two's champion teams would play in the AFL–NFL World Championship Game until the merger was to officially begin in 1970. After the merger, each league was re-designated as a "conference", and the game has since been played between the conference champions to determine the NFL's league champion. Currently, the National Football Conference leads the league with 27 wins to 26 wins for the American Football Conference. The Pittsburgh Steelers and the New England Patriots have the most Super Bowl championship titles, with six. The New England Patriots have the most Super Bowl appearances, with eleven.
The day on which the Super Bowl is played, now considered by some as an unofficial American national holiday, is called "Super Bowl Sunday". It is the second-largest day for U.S. food consumption, after Thanksgiving Day. In addition, the Super Bowl has frequently been the most-watched American television broadcast of the year; the seven most-watched broadcasts in U.S. television history are Super Bowls. In 2015, Super Bowl XLIX became the most-watched American television program in history with an average audience of 114.4 million viewers, the fifth time in six years the game had set a record, starting with Super Bowl XLIV, which itself had taken over the number-one spot held for 27 years by the final episode of M*A*S*H. The Super Bowl is also among the most-watched sporting events in the world, almost all audiences being North American, and is second to the UEFA Champions League final as the most watched annual sporting event worldwide.The NFL restricts the use of its "Super Bowl" trademark; it is frequently called the Big Game or other generic terms by non-sponsoring corporations. Because of the high viewership, commercial airtime during the Super Bowl broadcast is the most expensive of the year, leading to companies regularly developing their most expensive advertisements for this broadcast. As a result, watching and discussing the broadcast's commercials has become a significant aspect of the event. In addition, popular singers and musicians have performed during the event's pre-game and halftime ceremonies.Tawny owl
The tawny owl or brown owl (Strix aluco) is a stocky, medium-sized owl commonly found in woodlands 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 rodents, 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 owl 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 and its asymmetrically placed ears are key to its hunting by giving it excellent directional hearing. Its nocturnal habits and eerie, easily imitated call, have led to a mythical association of the tawny owl with bad luck and death.True owl
The true owls or typical owls (family Strigidae) are one of the two generally accepted families of owls, the other being the barn owls (Tytonidae). The Sibley-Ahlquist taxonomy unites the Caprimulgiformes with the owl order; here, the typical owls are a subfamily Striginae. This is unsupported by more recent research (see Cypselomorphae for details), but the relationships of the owls in general are still unresolved. This large family comprises nearly 220 living species in 25 genera. The typical owls have a cosmopolitan distribution and are found on every continent except Antarctica.Web Ontology Language
The Web Ontology Language (OWL) is a family of knowledge representation languages for authoring ontologies. Ontologies are a formal way to describe taxonomies and classification networks, essentially defining the structure of knowledge for various domains: the nouns representing classes of objects and the verbs representing relations between the objects. Ontologies resemble class hierarchies in object-oriented programming but there are several critical differences. Class hierarchies are meant to represent structures used in source code that evolve fairly slowly (typically monthly revisions) whereas ontologies are meant to represent information on the Internet and are expected to be evolving almost constantly. Similarly, ontologies are typically far more flexible as they are meant to represent information on the Internet coming from all sorts of heterogeneous data sources. Class hierarchies on the other hand are meant to be fairly static and rely on far less diverse and more structured sources of data such as corporate databases.The OWL languages are characterized by formal semantics. They are built upon the World Wide Web Consortium's (W3C) XML standard for objects called the Resource Description Framework (RDF). OWL and RDF have attracted significant academic, medical and commercial interest.
In October 2007, a new W3C working group was started to extend OWL with several new features as proposed in the OWL 1.1 member submission. W3C announced the new version of OWL on 27 October 2009. This new version, called OWL 2, soon found its way into semantic editors such as Protégé and semantic reasoners such as Pellet, RacerPro, FaCT++ and HermiT.The OWL family contains many species, serializations, syntaxes and specifications with similar names. OWL and OWL2 are used to refer to the 2004 and 2009 specifications, respectively. Full species names will be used, including specification version (for example, OWL2 EL). When referring more generally, OWL Family will be used.