The British Museum, in the Bloomsbury area of London, United Kingdom, is a public institution dedicated to human history and culture. Its permanent collection of some eight million works is among the largest and most comprehensive in existence, having been sourced during the era of the British Empire, it documents the story of human culture from its beginnings to the present. It was the first public national museum in the world; the British Museum was established in 1753 based on the collections of the Irish physician and scientist Sir Hans Sloane. It first opened in Montagu House, on the site of the current building, its expansion over the following 250 years was a result of expanding British colonisation and has resulted in the creation of several branch institutions, the first being the Natural History Museum in 1881. In 1973, the British Library Act 1972 detached the library department from the British Museum, but it continued to host the now separated British Library in the same Reading Room and building as the museum until 1997.
The museum is a non-departmental public body sponsored by the Department for Digital, Culture and Sport, as with all national museums in the UK it charges no admission fee, except for loan exhibitions. Its ownership of some of its most famous objects originating in other countries is disputed and remains the subject of international controversy, most notably in the case of the Parthenon Marbles. Although today principally a museum of cultural art objects and antiquities, the British Museum was founded as a "universal museum", its foundations lie in the will of the Irish physician and naturalist Sir Hans Sloane, a London-based doctor and scientist from Ulster. During the course of his lifetime, after he married the widow of a wealthy Jamaican planter, Sloane gathered a large collection of curiosities and, not wishing to see his collection broken up after death, he bequeathed it to King George II, for the nation, for a sum of £20,000. At that time, Sloane's collection consisted of around 71,000 objects of all kinds including some 40,000 printed books, 7,000 manuscripts, extensive natural history specimens including 337 volumes of dried plants and drawings including those by Albrecht Dürer and antiquities from Sudan, Greece, the Ancient Near and Far East and the Americas.
On 7 June 1753, King George II gave his Royal Assent to the Act of Parliament which established the British Museum. The British Museum Act 1753 added two other libraries to the Sloane collection, namely the Cottonian Library, assembled by Sir Robert Cotton, dating back to Elizabethan times, the Harleian Library, the collection of the Earls of Oxford, they were joined in 1757 by the "Old Royal Library", now the Royal manuscripts, assembled by various British monarchs. Together these four "foundation collections" included many of the most treasured books now in the British Library including the Lindisfarne Gospels and the sole surviving manuscript of Beowulf; the British Museum was the first of a new kind of museum – national, belonging to neither church nor king open to the public and aiming to collect everything. Sloane's collection, while including a vast miscellany of objects, tended to reflect his scientific interests; the addition of the Cotton and Harley manuscripts introduced a literary and antiquarian element and meant that the British Museum now became both National Museum and library.
The body of trustees decided on a converted 17th-century mansion, Montagu House, as a location for the museum, which it bought from the Montagu family for £20,000. The trustees rejected Buckingham House, on the site now occupied by Buckingham Palace, on the grounds of cost and the unsuitability of its location. With the acquisition of Montagu House, the first exhibition galleries and reading room for scholars opened on 15 January 1759. At this time, the largest parts of collection were the library, which took up the majority of the rooms on the ground floor of Montagu House and the natural history objects, which took up an entire wing on the second state storey of the building. In 1763, the trustees of the British Museum, under the influence of Peter Collinson and William Watson, employed the former student of Carl Linnaeus, Daniel Solander to reclassify the natural history collection according to the Linnaean system, thereby making the Museum a public centre of learning accessible to the full range of European natural historians.
In 1823, King George IV gave the King's Library assembled by George III, Parliament gave the right to a copy of every book published in the country, thereby ensuring that the museum's library would expand indefinitely. During the few years after its foundation the British Museum received several further gifts, including the Thomason Collection of Civil War Tracts and David Garrick's library of 1,000 printed plays; the predominance of natural history and manuscripts began to lessen when in 1772 the museum acquired for £8,410 its first significant antiquities in Sir William Hamilton's "first" collection of Greek vases. From 1778, a display of objects from the South Seas brought back from the round-the-world voyages of Captain James Cook and the travels of other explorers fascinated visitors with a glimpse of unknown lands; the bequest of a collection of books, engraved gems, coins and drawings by Clayton Mordaunt Cracherode in 1800 did much to raise the museum's reputation. The museum's first notable addition towards its collection of antiquities, since its foundation, was by Sir William Hamilton, British Ambassador to Naples, who sold his collection of Greek and Roman artefacts to
Antarctica is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere entirely south of the Antarctic Circle, is surrounded by the Southern Ocean. At 14,200,000 square kilometres, it is the fifth-largest continent. For comparison, Antarctica is nearly twice the size of Australia. About 98% of Antarctica is covered by ice that averages 1.9 km in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula. Antarctica, on average, is the coldest and windiest continent, has the highest average elevation of all the continents. Most of Antarctica is a polar desert, with annual precipitation of only 200 mm along the coast and far less inland; the temperature in Antarctica has reached −89.2 °C, though the average for the third quarter is −63 °C. Anywhere from 1,000 to 5,000 people reside throughout the year at research stations scattered across the continent. Organisms native to Antarctica include many types of algae, fungi, plants and certain animals, such as mites, penguins and tardigrades.
Vegetation, where it occurs, is tundra. Antarctica is noted as the last region on Earth in recorded history to be discovered, unseen until 1820 when the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny sighted the Fimbul ice shelf; the continent, remained neglected for the rest of the 19th century because of its hostile environment, lack of accessible resources, isolation. In 1895, the first confirmed. Antarctica is a de facto condominium, governed by parties to the Antarctic Treaty System that have consulting status. Twelve countries signed the Antarctic Treaty in 1959, thirty-eight have signed it since then; the treaty prohibits military activities and mineral mining, prohibits nuclear explosions and nuclear waste disposal, supports scientific research, protects the continent's ecozone. Ongoing experiments are conducted by more than 4,000 scientists from many nations; the name Antarctica is the romanised version of the Greek compound word ἀνταρκτική, feminine of ἀνταρκτικός, meaning "opposite to the Arctic", "opposite to the north".
Aristotle wrote in his book Meteorology about an Antarctic region in c. 350 BC Marinus of Tyre used the name in his unpreserved world map from the 2nd century CE. The Roman authors Hyginus and Apuleius used for the South Pole the romanised Greek name polus antarcticus, from which derived the Old French pole antartike attested in 1270, from there the Middle English pol antartik in a 1391 technical treatise by Geoffrey Chaucer. Before acquiring its present geographical connotations, the term was used for other locations that could be defined as "opposite to the north". For example, the short-lived French colony established in Brazil in the 16th century was called "France Antarctique"; the first formal use of the name "Antarctica" as a continental name in the 1890s is attributed to the Scottish cartographer John George Bartholomew. The long-imagined south polar continent was called Terra Australis, sometimes shortened to'Australia' as seen in a woodcut illustration titled Sphere of the winds, contained in an astrological textbook published in Frankfurt in 1545.
Although the longer Latin phrase was better known, the shortened name Australia was used in Europe's scholarly circles. In the nineteenth century, the colonial authorities in Sydney removed the Dutch name from New Holland. Instead of inventing a new name to replace it, they took the name Australia from the south polar continent, leaving it nameless for some eighty years. During that period, geographers had to make do with clumsy phrases such as "the Antarctic Continent", they searched for a more poetic replacement, suggesting various names such as Antipodea. Antarctica was adopted in the 1890s. Antarctica has no indigenous population, there is no evidence that it was seen by humans until the 19th century. However, in February 1775, during his second voyage, Captain Cook called the existence of such a polar continent "probable" and in another copy of his journal he wrote:" believe it and it's more than probable that we have seen a part of it". However, belief in the existence of a Terra Australis—a vast continent in the far south of the globe to "balance" the northern lands of Europe and North Africa—had prevailed since the times of Ptolemy in the 1st century AD.
In the late 17th century, after explorers had found that South America and Australia were not part of the fabled "Antarctica", geographers believed that the continent was much larger than its actual size. Integral to the story of the origin of Antarctica's name is that it was not named Terra Australis—this name was given to Australia instead, because of the misconception that no significant landmass could exist further south. Explorer Matthew Flinders, in particular, has been credited with popularising the transfer of the name Terra Australis to Australia, he justified the titling of his book A Voyage to Terra Australis by writing in the introduction: There is no probability, that any other detached body of land, of nearly equal extent, will be found in a more southern latitude.
Pygmy owls are members of the genus Glaucidium. They belong to Strigidae; the genus consists of about 26 to 35 species distributed worldwide. The exact number of species is somewhat disputed; these are small owls, some of the species are called "owlets". Most pygmy owl species are nocturnal and hunt large insects and other small prey. Glaucidium forms a paraphyletic group with Surnia. Eurasian pygmy owl Collared owlet Pearl-spotted owlet Northern pygmy owl Mountain pygmy owl Baja pygmy owl Guatemalan pygmy owl Costa Rican pygmy owl Andean pygmy owl Cloud-forest pygmy owl Yungas pygmy owl, Colima pygmy owl, Tamaulipas pygmy owl Pernambuco pygmy owl Central American pygmy owl Subtropical pygmy owl Amazonian pygmy owl East Brazilian pygmy owl Ferruginous pygmy owl Pacific pygmy owl Austral pygmy owl Cuban pygmy owl Red-chested owlet Sjöstedt's barred owlet Asian barred owlet Javan owlet Jungle owlet Chestnut-backed owlet African barred owlet Albertine owlet †Glaucidium kurochkiniThe supposed prehistoric species "Glaucidium" dickinsoni is now recognized as a burrowing owl a paleosubspecies providentiae.
Bones of an indeterminate Glaucidium have been recovered from Late Pliocene deposits in Poland. Mlíkovský, Jirí: Cenozoic Birds of the World, Part 1: Europe: 215. Ninox Press, Prague. ISBN 80-901105-3-8 PDF fulltext Pygmy owl information Mountain Pygmy Owl Mountain Pygmy Owl "eyes in back of head" Ferruginous pygmy owl Colima pygmy owl Eurasian pygmy owl "Big fight over tiny owl" - CNN/AP article on pygmy owl's endangered species status in Arizona' Pygmy Owls - documentary produced by Oregon Field Guide The Neblina Pygmy owl - 2018 BBC internet article on new species found in the Pico da Neblina National Park, Brazil
In scientific nomenclature, a synonym is a scientific name that applies to a taxon that goes by a different scientific name, although the term is used somewhat differently in the zoological code of nomenclature. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies; this name is no longer in use: it is now a synonym of the current scientific name, Picea abies. Unlike synonyms in other contexts, in taxonomy a synonym is not interchangeable with the name of which it is a synonym. In taxonomy, synonyms have a different status. For any taxon with a particular circumscription and rank, only one scientific name is considered to be the correct one at any given time. A synonym cannot exist in isolation: it is always an alternative to a different scientific name. Given that the correct name of a taxon depends on the taxonomic viewpoint used a name, one taxonomist's synonym may be another taxonomist's correct name. Synonyms may arise whenever the same taxon is named more than once, independently.
They may arise when existing taxa are changed, as when two taxa are joined to become one, a species is moved to a different genus, a variety is moved to a different species, etc. Synonyms come about when the codes of nomenclature change, so that older names are no longer acceptable. To the general user of scientific names, in fields such as agriculture, ecology, general science, etc. A synonym is a name, used as the correct scientific name but, displaced by another scientific name, now regarded as correct, thus Oxford Dictionaries Online defines the term as "a taxonomic name which has the same application as another one, superseded and is no longer valid." In handbooks and general texts, it is useful to have synonyms mentioned as such after the current scientific name, so as to avoid confusion. For example, if the much advertised name change should go through and the scientific name of the fruit fly were changed to Sophophora melanogaster, it would be helpful if any mention of this name was accompanied by "".
Synonyms used in this way may not always meet the strict definitions of the term "synonym" in the formal rules of nomenclature which govern scientific names. Changes of scientific name have two causes: they may be taxonomic or nomenclatural. A name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight. A name change may be due to purely nomenclatural reasons, that is, based on the rules of nomenclature. Speaking in general, name changes for nomenclatural reasons have become less frequent over time as the rules of nomenclature allow for names to be conserved, so as to promote stability of scientific names. In zoological nomenclature, codified in the International Code of Zoological Nomenclature, synonyms are different scientific names of the same taxonomic rank that pertain to that same taxon. For example, a particular species could, over time, have had two or more species-rank names published for it, while the same is applicable at higher ranks such as genera, orders, etc.
In each case, the earliest published name is called the senior synonym, while the name is the junior synonym. In the case where two names for the same taxon have been published the valid name is selected accorded to the principle of the first reviser such that, for example, of the names Strix scandiaca and Strix noctua, both published by Linnaeus in the same work at the same date for the taxon now determined to be the snowy owl, the epithet scandiaca has been selected as the valid name, with noctua becoming the junior synonym. One basic principle of zoological nomenclature is that the earliest published name, the senior synonym, by default takes precedence in naming rights and therefore, unless other restrictions interfere, must be used for the taxon. However, junior synonyms are still important to document, because if the earliest name cannot be used the next available junior synonym must be used for the taxon. For other purposes, if a researcher is interested in consulting or compiling all known information regarding a taxon, some of this may well have been published under names now regarded as outdated and so it is again useful to know a list of historic synonyms which may have been used for a given current taxon name.
Objective synonyms refer to taxa with same rank. This may be species-group taxa of the same rank with the same type specimen, genus-group taxa of the same rank with the same type species or if their type species are themselves objective synonyms, of family-group taxa with the same type genus, etc. In the case of subjective synonyms, there is no such shared type, so the synonymy is open to taxonomic judgement, meaning that th
Eastern screech owl
The eastern screech owl or eastern screech-owl is a small owl, common in Eastern North America, from Mexico to Canada. This species is native to most wooded environments of its distribution, more so than any other owl in its range, has adapted well to manmade development, although it avoids detection due to its nocturnal habits. Adults range from 16 to 25 cm in length and weigh 121–244 g. Among the differently sized races, length can average from 19.5 to 23.8 cm. The wingspan can range from 46 to 61 cm. In Ohio, male owls average 166 g and females 194 g while in central Texas, they average 157 g and 185 g, respectively, they have either dark gray intricately patterned plumage with streaking on the underparts. Midsized by screech-owl standards, these birds are stocky, short-tailed and broad-winged as is typical of the genus, they have a large, round head with prominent ear tufts, yellow eyes, a yellowish beak, which measures on average 1.45 cm in length. The feet are large and powerful compared to more southern screech owls and are feathered down to the toes, although the southernmost populations only have remnant bristles rather than full feathering on the legs and feet.
The eastern screech owl are some of the heaviest screech owls, the largest tropical screech owls do not exceed them in average or maximal weight, but they are surpassed in length by Balsas, long-tufted, white-throated, rufescent owls, in increasing order. Two color variations are referred to as "red or rufous morphs" and "gray morphs" by bird watchers and ornithologists. Rusty birds are more common in the southern parts of the range. While the gray morph provides remarkably effective camouflage amongst the bark of hardwood trees, red morphs may find security in certain pine trees and the colorful leaves of changing deciduous trees; the highest percentage of red morphs is known from Illinois. A rarer "brown morph" is known, recorded in the south, which may be the occasional product of hybridation between the morphs. In Florida, brown morphs are reported in the more humid portions of the state, whereas they appear to be absent in the northern and northwestern parts of the state. A paler gray variation exists in western Canada and the north-central United States.
In the related western screech owl, no "morphs" are seen, as all owls of the western species are gray. Besides coloration, the western screech owl is of exactly the same general appearance and size as the eastern; the only reliable distinguishing feature is the bill color, darker in the western and olive-yellow in the eastern. The eastern and western screech owls overlap in the range in the Rio Grande valley at the Texas–Mexico border and the riparian woods of the Cimarron tributary of the Arkansas River on the edge of southern Great Plains. Other somewhat similar species that may abut the eastern screech owl's range in its western and southernmost distribution, like the Middle American screech owl, whiskered screech owl, the flammulated owl, are distinguished by their smaller body and foot size, different streaking pattern on breast, different bare part coloration, distinctive voices. Through much of the eastern United States, eastern screech owls are physically unmistakable, because other owls with ear tufts are much larger and differently colored and the only other small owl, the northern saw-whet owl is smaller, with no ear tufts, a more defined facial disc, browner overall color.
Five subspecies are treated for the eastern screech owl, but the taxonomy in the species is considered "muddled". Much of the variation may be considered clinal, as predictably, the size tends to decrease from north to south and much of the color variation is explainable by adaptation to habitat. M. a. asio includes described races no longer considered valid such as M. a. carolinensis, M. a. naevius and M. a. striatus. It is resident from eastern Minnesota to southwestern Quebec and southern New Hampshire south to Missouri and northern South Carolina. Dorsal color is cold gray; the nominate's markings are coarse and sparse and its toes are densely feathered. Its primary song has a terminal, tremulous whinny; this is a medium-to-large race. The owls of southern Ontario are on the larger end of the scale, of similar size to the big owls of Colorado and Wyoming. M. a. maxwelliae. Includes M. a. swenki. Resident from central Montana, southeastern Saskatchewan, southern Manitoba south to western Kansas.
This race is similar to M. a. asio but dorsal color tends to be a paler gray, the ventrum being whiter and less marked and red morphs tending to paler and rarer. With a wing chord length of 15 to 18 cm, this is the largest race in average linea
The northern hawk-owl is a medium sized true owl of the northern latitudes. It is non-migratory and stays within its breeding range, though it sometimes irrupts southward, it is one of the few owls, neither nocturnal nor crepuscular, being active only during the day. This is the only living species in the genus Surnia of the "typical" owls; the species is sometimes called the hawk owl. The genus name Surnia appears to be a word made up by A. M. C. Duméril, the creator of the genus, ulula is Latin for a screech owl. Male northern hawk-owls are 36–42.5 cm long and weigh 300 g. Females are bigger with a length of 37.2–44.7 cm and a mass of about 340 g. Both male and female have similar wingspans of about 45 cm; the northern hawk-owl plumage is dark brown with an off-white spotting pattern on all dorsal parts of the body with the exception of the back of the neck which boasts a black v-shaped pattern. The underbelly is white or off-white which continues to the toes with brown bands on the breast and stomach.
It boasts a long tail with brown banding. The northern hawk-owl has a smokey white face with a black border, a flat head, yellow eyes and a yellow curved beak; the northern hawk-owl has been said to resemble a hawk in behavior. In North America, its appearance in flight is considered similar to a Cooper's hawk, it has been suggested that this may be because the hawk-owl may fill an important diurnal niche similar to that of day hunters such as hawks. S. ulula has a variety of calls used by the different sexes in different situations. When attracting a mate the male lets out a rolled whistle of ulululululululul and a sound similar to tu-wita-wit, tiwita-tu-wita, when perching at a potential nest site; the female’s call is less constant and more shrill. When alerting to danger, the northern hawk-owl lets out a sound similar to rike, rike, rike, it releases a high pitched scream followed by a yip when an intruder is near to the nest. To warn of impending dangers to a fledgling, the hawk-owl will let out a noise similar to ki ki kikikikiki.
Calls can vary in length from 15 s to 2 min. Three subspecies exist across the northern holarctic; the North American subspecies S. u. caparoch spans from eastern Alaska through Canada to Newfoundland and in some areas extends south into northern United States. The other two subspecies are found in Eurasia: S. u. tianschanica breeds in central Asia reaching Xinjiang and S. u. ulula resides across Eurasia reaching Siberia at its most eastern range. S. u. caparoch can extend its territory as far south as northern Minnesota and many other states in the northern United States including more central states such as West Virginia, New York, South Dakota. These southern forays into the northern United States are rare and occur during winter, or following an explosion in a population of prey. S. u. caparoch can be found in more southern areas such as Great Britain, southern Russia and Scandinavia, following explosions of prey. Northern hawk-owls are unevenly distributed and variable throughout the boreal forest.
They live in open coniferous forests, or coniferous forests mixed with deciduous species such as larch, birch and willow. They are found in muskegs, swamp valleys, meadows, or burnt areas, avoid dense spruce-fir forests. Winter habitat is the same as breeding habitat; the northern hawk-owl starts its mating rituals at the beginning of March. After calling and pairing is complete the northern hawk-owl will start to lay eggs. On average the northern hawk-owl will lay 3–11 eggs per brood; the nest sites are the tops of hollow stumps of old dead spruce trees. These nesting sites are 2–10 m above ground for the North American S. u. caparoch and 4–5 m above ground for the Eurasian S. u. ulala. The specific dates of egg appearance can be quite variable depending on locality. In central Canada eggs are laid from March 30 to the 5th of June. On Newfoundland the appearance of eggs occurs between May 9 and June 11. In Finland however, eggs can be found anywhere between the 30th of March to the 23rd of June.
For the most part the female northern hawk-owl does the incubating of the eggs whilst the male forages for food. Once the chicks have hatched their roles shift drastically. At about two weeks into the chicks' lives the female starts to leave the nest for long spans of time; this span of time is when the female hunts. The male however, will guard the nest diligently; when predators fly nearby, the male will sometimes chase them away from the nest if he feels it is necessary. Once the owlets have grown to a size which allows less parental supervision, they will leave the nest; this occurs on average after their 21st day, can begin as early as mid-June. After this the female will provide most of the care. However, the male will still feed his young on occasion; the northern hawk-owl has been known to nest on cliffsides. It has little fear of humans, will attack if the young are approached too closely; the northern hawk-owl feeds on a variety of prey, which can include small rodents to mammals more robust in size, a variety of birds, a typical diet for many boreal owls.
In Eurasia the northern hawk-owl is known to feed on voles from the Microtus family. These voles follow a 3
Blakiston's fish owl
Blakiston's fish owl, the largest living species of owl, is a fish owl, a sub-group of eagle owls which specialize in hunting in riparian areas. This species is a part of the family known as typical owls. Blakiston's fish owl and three related species were placed in the genus Ketupa, its habitat is riparian forest, with large, old trees for nest-sites, near lakes, rivers and shoals that don't freeze in winter. Henry Seebohm named this bird after the English naturalist Thomas Blakiston, who collected the original specimen in Hakodate on Hokkaidō, Japan in 1883, it is more correct to call this species the Blakiston's eagle owl. This is because it is more related to the Eurasian eagle-owl by studies of the main subgenus of the species, B. b. dumeril, than to the subgenus of fish owls that it was believed to be more close to, i.e. Ketupu; this was proven by osteological and DNA-based tests in 2003 by ornithologists/taxonomists Michael Wink and Claus König, author of Owls of the World. However, the other fish owls are not believed to be divergent enough to support a separate genus either and now all fish owls are also included in the genus Bubo.
Given that it shares genetic material osteological characteristics with the eagle-owl and seems to share some characteristics with the other three fish owls, the place of the Blakiston's fish owls in this evolutionary chain is ambiguous. Some authors have wondered whether the Blakiston's represents an intermediate step between traditional eagle-owls and the other fish owls, despite the current gap in distribution between Blakiston's and other fish owls. Whether other Asian eagle-owls with sideways slanting ear-tufts, namely the spot-bellied, the barred and the somewhat superficially fish owl-like dusky eagle-owl are related to the fish owls and/or the Blakiston's is unclear. Despite a few authors include them in Bubo, the fishing owls of Africa classified in the genus Scotopelia, seem to be unrelated in every major way, based on external characteristics and preliminary genetic materials, to the fish owls and it is unclear how, if, they are related to typical eagle-owls. Blakiston's fish owl is the largest living species of owl.
A pair field study of the species showed males weighing from 2.95 to 3.6 kg, while the female, at up to 2.95 to 4.6 kg, is about 25% larger. Around February, the average weight of Russian fish owls was 3.1 kg in males and 3.25 kg in females when their body mass at its lowest throughout the year. Blakiston's fish owl measures 60 to 72 cm in total length, thus measures less at average and maximum length than the great gray owl, a species which has a lower body mass; the Eurasian eagle-owl is sometimes considered the largest overall living owl species. The three largest races of eagle-owl, all found in Siberia and the Russian Far East, are close in size to the Blakiston's fish owl. According to Heimo Mikkola, the largest specimen of eagle-owl was 30 mm longer in bill-to-tail length than the longest Blakiston's fish owl, while the top weight of the two species is the same; the longest great gray owl was 120 mm longer than the biggest Blakiston's fish owl but would be about 2.5 times lighter than the weight of the largest female Blakiston's.
However, the average measurements of Blakiston's fish owl surpass the average measurements of the Eurasian eagle-owl in the three major categories: weight and wingspan, making Blakiston's the overall largest species of owl. The large Siberian races of eagle-owl are smaller on average than the Blakiston's, at least in terms of body mass and wing size; the maximum wingspan of the Blakiston's fish owl is greater than any known eagle-owl. The wingspan range known for Blakiston's fish owls is 178 to 190 cm, it is possible the largest specimens can attain a wingspan of 200 cm. The Blakiston's is noticeably larger than the other three extant species of fish owl. In terms of structure, the Blakiston's fish owl is more similar to eagle-owls than it is to other fish owls but it shares a few characteristics with both types of owl. Like all fish owls, its bill is long, the body husky and wings are long compared to eagle-owls, it shares with other fish owls a comparatively long tarsi, although relative to their size the three smaller fish owl have a proportionately longer tarsus.
Other than these few characteristics, a Blakiston's fish owl skull and skeleton is the same as that of a Eurasian eagle-owl. The talons of the Blakiston's fish owl are similar in shape and size to those of the Eurasian eagle-owls, it has been stated that the combination of wavy cross patterns on the underside of the Blakiston's plumage and its huge talons make it look strikingly like an outsized great horned owl from below. Two external characteristics that Blakiston's share with eagle-owls, but not with the other fish owls, is that its tarsi are feathered and that its wing beats are silent, although the Blakiston's has fewer sound-blocking combs on its wing primaries than the a comparable eagle-owl would. Among standard measurements, which at average and maximum are greater than any other living owl other than tail length, the wing chord measures 447–560 mm, the tail measures 243–305 mm, the tarsus is 73–102