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Las aves son un grupo de vertebrados de sangre caliente que constituyen la clase Aves ( / ˈ eɪ v iː z / ), caracterizadas por plumas , mandíbulas picudas desdentadas, la puesta de huevos de cáscara dura , una alta tasa metabólica , un corazón de cuatro cámaras, y un esqueleto fuerte pero liviano. Las aves viven en todo el mundo y varían en tamaño desde el colibrí abeja de 5,5 cm (2,2 pulgadas) hasta el avestruz común de 2,8 m (9 pies 2 pulgadas). Hay más de 11.000 especies vivas, más de la mitad de las cuales son paseriformes o aves que se posan. Las aves tienen alas cuyo desarrollo varía según la especie; los únicos grupos conocidos sin alas son los extintos moa y los pájaros elefante . Las alas, que son extremidades anteriores modificadas , dieron a las aves la capacidad de volar, aunque una mayor evolución ha llevado a la pérdida del vuelo en algunas aves , incluidas las ratites , los pingüinos y diversasespecies isleñas endémicas . Los sistemas digestivo y respiratorio de las aves también están especialmente adaptados para volar. Algunas especies de aves de ambientes acuáticos, particularmente aves marinas y algunas acuáticas , han evolucionado aún más para nadar. El estudio de las aves se llama ornitología .

Las aves son dinosaurios terópodos emplumados y constituyen los únicos dinosaurios vivos conocidos . Asimismo, las aves son consideradas reptiles en el sentido cladístico moderno del término, y sus parientes vivos más cercanos son los cocodrilos . Las aves son descendientes de los avianos primitivos (cuyos miembros incluyen Archaeopteryx ) que aparecieron por primera vez durante el Jurásico tardío . Según estimaciones recientes, las aves modernas ( Neornithes ) evolucionaron a finales del Cretácico y se diversificaron drásticamente en la época del evento de extinción Cretácico-Paleógeno hace 66 millones de años, que acabó con los pterosaurios y todos los dinosaurios no aviares.

Muchas especies sociales transmiten conocimientos de generación en generación, lo que se considera una forma de cultura . Las aves son sociales, se comunican con señales visuales, llamados y cantos , y participan en comportamientos tales como la cría y caza cooperativas , las bandadas y el acoso de depredadores. La gran mayoría de las especies de aves son socialmente (pero no necesariamente sexualmente) monógamas , generalmente durante una temporada de reproducción a la vez, a veces durante años y rara vez de por vida. Otras especies tienen sistemas de reproducción que son poligínicos (un macho con muchas hembras) o, raramente, poliándricos (una hembra con muchos machos). Las aves producen descendencia poniendo huevos que son fertilizados mediante reproducción sexual . Por lo general , los padres los ponen en un nido y los incuban . La mayoría de las aves tienen un período prolongado de cuidado parental después de la eclosión.

Muchas especies de aves son económicamente importantes como alimento para el consumo humano y materia prima para la fabricación, siendo las aves domesticadas y no domesticadas fuentes importantes de huevos, carne y plumas. Los pájaros cantores , los loros y otras especies son populares como mascotas. El guano (excremento de pájaro) se cosecha para utilizarlo como fertilizante. Las aves figuran en toda la cultura humana. Entre 120 y 130 especies se han extinguido debido a la actividad humana desde el siglo XVII, y cientos más antes. La actividad humana amenaza con la extinción a unas 1.200 especies de aves, aunque se están realizando esfuerzos para protegerlas. La observación de aves recreativas es una parte importante de la industria del ecoturismo . ( Articulo completo... )

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Artículos relacionados


  • El pitohui encapuchado ( Pitohui dichrous ) es una especie de ave del género Pitohui que se encuentra en Nueva Guinea . Durante mucho tiempo se pensó que era un silbador ( Pachycephalidae ), pero ahora se sabe que pertenece a la familia de los oropéndolas del Viejo Mundo (Oriolidae). Dentro de la familia de los oropéndolas, esta especie está más estrechamente relacionada con los pitohuis variables del género Pitohui , y luego con las higueras . Un pájaro cantor de tamaño mediano con plumaje marrón rojizo y negro, esta especie es una de las pocas aves venenosas conocidas y contiene una variedad de compuestos de batracotoxina en su piel, plumas y otros tejidos. Se cree que estas toxinas se derivan de su dieta y pueden funcionar tanto para disuadir a los depredadores como para proteger al ave de los parásitos. El gran parecido de esta especie con otras aves no relacionadas también conocidas como pitohuis que también son venenosas es un ejemplo de evolución convergente y mimetismo mülleriano . Su apariencia también es imitada por especies no venenosas no relacionadas, un fenómeno conocido como mimetismo batesiano . La naturaleza tóxica de esta ave es bien conocida por los cazadores locales, que la evitan. Es una de las especies de pitohui más venenosas, pero la toxicidad de cada ave puede variar geográficamente. El pitohui encapuchado se encuentra en bosques desde el nivel del mar hasta los 2000 m (6600 pies), pero es más común en colinas y montañas bajas. Es un ave social que vive en grupos familiares y con frecuencia se une e incluso lidera bandadas de especies mixtas en busca de alimento . Su dieta se compone de frutas, semillas e invertebrados. Aparentemente, esta especie se reproduce en forma cooperativa, con grupos familiares que ayudan a proteger el nido y alimentar a las crías. El pitohui capucho es común y actualmente no se encuentra en riesgo de extinción , manteniéndose estable su número. ( Articulo completo... )




  • El canto de un estornino común

    The common starling (Sturnus vulgaris), also known as the European starling in North America and simply as the starling in Great Britain and Ireland, is a medium-sized passerine bird in the starling family, Sturnidae. It is about 20 cm (8 in) long and has glossy black plumage with a metallic sheen, which is speckled with white at some times of year. The legs are pink and the bill is black in winter and yellow in summer; young birds have browner plumage than the adults. It is a noisy bird, especially in communal roosts and other gregarious situations, with an unmusical but varied song. Its gift for mimicry has been noted in literature including the Mabinogion and the works of Pliny the Elder and William Shakespeare.

    The common starling has about 12 subspecies breeding in open habitats across its native range in temperate Europe and across the Palearctic to western Mongolia, and it has been introduced as an invasive species to Australia, New Zealand, Canada, the United States, Mexico, Argentina, South Africa and Fiji. This bird is resident in western and southern Europe and southwestern Asia, while northeastern populations migrate south and west in the winter within the breeding range and also further south to Iberia and North Africa. The common starling builds an untidy nest in a natural or artificial cavity in which four or five glossy, pale blue eggs are laid. These take two weeks to hatch and the young remain in the nest for another three weeks. There are normally one or two breeding attempts each year. This species is omnivorous, taking a wide range of invertebrates, as well as seeds and fruit. It is hunted by various mammals and birds of prey, and is host to a range of external and internal parasites.

    Large flocks typical of this species can be beneficial to agriculture by controlling invertebrate pests; however, starlings can also be pests themselves when they feed on fruit and sprouting crops. Common starlings may also be a nuisance through the noise and mess caused by their large urban roosts. Introduced populations in particular have been subjected to a range of controls, including culling, but these have had limited success, except in preventing the colonisation of Western Australia. (Full article...)

  • Looking north across the reserve

    Cley Marshes is a 176-hectare (430-acre) nature reserve on the North Sea coast of England just outside the village of Cley next the Sea, Norfolk. A reserve since 1926, it is the oldest of the reserves belonging to the Norfolk Wildlife Trust (NWT), which is itself the oldest county Wildlife Trust in the United Kingdom. Cley Marshes protects an area of reed beds, freshwater marsh, pools and wet meadows and is part of the North Norfolk Coast Site of Special Scientific Interest (SSSI), Special Area of Conservation (SAC), Special Protection Area (SPA), and Ramsar Site due to the large numbers of birds it attracts.

    The reserve is important for some scarce breeding species, such as pied avocets on the islands, and western marsh harriers, Eurasian bitterns and bearded reedlings in the reeds, and is also a major migration stopoff and wintering site. There are also several nationally or locally scarce invertebrates and plants specialised for this coastal habitat. It has five bird hides and an environmentally friendly visitor centre and further expansion is planned through the acquisition of neighbouring land and improvements to visitor facilities.

    The site has a long history of human occupation, from prehistoric farming to its use as a prisoner of war camp in the Second World War. The reserve attracts large numbers of visitors, contributing significantly to the economy of Cley village. Despite centuries of embankment to reclaim land and protect the village, the marshes have been flooded many times, and the southward march of the coastal shingle bank and encroachment by the sea make it inevitable that the reserve will eventually be lost. New wetlands are being created further inland to compensate for the loss of coastal habitats. (Full article...)

  • Plate 21 depicting a male red-capped parrakeet

    Illustrations of the Family of Psittacidae, or Parrots is an 1832 book containing 42 hand-coloured lithographs by Edward Lear. He produced 175 copies for sale to subscribers as a part-publication, which were later bound as a book. Lear started painting parrots in 1830 when he was 18 years old, and to get material for his book he studied live birds at the London Zoo and in private collections. The latter included those of Edward Smith Stanley, later 13th Earl of Derby, who had a large menagerie at Knowsley Hall, and Benjamin Leadbeater, a taxidermist and trader in specimens. Lear drew onto lithographic plates for printing by Charles Joseph Hullmandel, who was known for the quality of his reproductions of fine art.

    Although the book was a financial failure, Lear's paintings of parrots established his reputation as one of the best natural history artists of his time. It found him work with John Gould, Stanley and other leading contemporary naturalists, and the young Queen Victoria engaged him to help her with her painting technique. Parrots was a forerunner to the major volumes of bird paintings by Gould, and Lear's work has influenced children's illustrators such as Beatrix Potter and Maurice Sendak as well as bird specialists like William T. Cooper, Elizabeth Butterworth and Walton Ford.

    Lear continued with his nature painting for some years, but from about 1835 he became concerned about his failing eyesight, and increasingly concentrated on his nonsense works and landscape painting, although he may have contributed to the illustrations for Charles Darwin's Voyage of the Beagle. (Full article...)

  • Mounted skin in the National Museum of Scotland, one of three in existence

    The Mauritius blue pigeon (Alectroenas nitidissimus) is an extinct species of blue pigeon formerly endemic to the Mascarene island of Mauritius in the Indian Ocean east of Madagascar. It has two extinct relatives from the Mascarenes and three extant ones from other islands. It is the type species of the genus of blue pigeons, Alectroenas. It had white hackles around the head, neck and breast and blue plumage on the body, and it was red on the tail and the bare parts of the head. These colours were thought similar to those of the Dutch flag, a resemblance reflected in its French common name, Pigeon Hollandais. The juveniles may have been partially green. It was 30 cm (12 in) long and larger and more robust than any other blue pigeon species. It fed on fruits, nuts, and molluscs, and was once widespread in the forests of Mauritius.

    The bird was first mentioned in the 17th century and was described several times thereafter, but very few accounts describe the behaviour of living specimens. The oldest record of the species is two sketches from a 1601–1603 ship's journal. Several stuffed specimens reached Europe in the 18th and 19th centuries, while only three stuffed specimens exist today. A live bird kept in the Netherlands around 1790 was long thought to have been a Mauritius blue pigeon, but examination of illustrations depicting it have shown it was most likely a Seychelles blue pigeon. The species is thought to have become extinct in the 1830s due to deforestation and predation. (Full article...)

  • Papuan mountain pigeon

    Mountain pigeons are four species of birds in the genus Gymnophaps in the pigeon family Columbidae. They are found on islands in eastern Indonesia and Melanesia, where they inhabit hill and montane forest. Medium-sized pigeons with long tails and wings, they are 33–38.5 cm (13.0–15.2 in) long and weigh 259–385 g (9.1–13.6 oz). They mostly have dull grey, white, or chestnut-brown plumage, their most distinctive feature being bright red skin around the eyes. Males and females mostly look alike, but the Papuan and pale mountain pigeons show slight sexual dimorphism. Mountain pigeons are very social and are usually seen in flocks of 10–40 birds, although some species can form flocks of more than 100 individuals. They are generally quiet and do not make many vocalisations apart from a distinctive whooshing noise while leaving their high-altitude roosts to feed in the morning.

    The genus was originally described by the Italian zoologist Tommaso Salvadori in 1874 and currently contains the Papuan, Seram, Buru, and pale mountain pigeons. The species are allopatric (having geographically separated populations) and form a single superspecies. Mountain pigeons are arboreal (tree-inhabiting) and feed on a wide variety of fruit-like figs and drupes, mainly foraging for food in the canopy. Nests can be of two types: a shallow depression in the forest floor or short grass; and a platform of sticks placed at a height of several metres in a tree. Clutches consist of a single white egg. All four species are listed as being of least concern on the IUCN Red List. (Full article...)

  • The elfin woods warbler (Setophaga angelae) is a species of bird endemic to Puerto Rico, where it is local and uncommon. Discovered in 1968 and described in 1972, it is the most recently described New World warbler (family Parulidae).

    The species name, angelae, is a tribute to Angela Kepler, one of its discoverers. These birds are insectivores, as they feed by gleaning small insects off the habitat leaves.

    Due to its small populations and restricted habitats, conservation efforts were begun in 1982 to protect this species, but as of 2005, the warbler was still in need of protection. The species is not in immediate danger as the majority of its habitat is protected forest, but introduced species (such as rats and small Asian mongooses), habitat reduction, and natural disasters represent potential threats to the population. (Full article...)

  • Adult

    The northern gannet (Morus bassanus) is a seabird, the largest species of the gannet family, Sulidae. It is native to the coasts of the Atlantic Ocean, breeding in Western Europe and Northeastern North America. It is the largest seabird in the northern Atlantic. The sexes are similar in appearance. The adult northern gannet has a mainly white streamlined body with a long neck, and long and slender wings. It is 87–100 cm (34+1⁄2–39+1⁄2 in) long with a 170–180 cm (67–71 in) wingspan. The head and nape have a buff tinge that is more prominent in breeding season, and the wings are edged with dark brown-black feathers. The long, pointed bill is blue-grey, contrasting with black, bare skin around the mouth and eyes. Juveniles are mostly grey-brown, becoming increasingly white in the five years it takes them to reach maturity.

    Nesting takes place in colonies on both sides of the North Atlantic, the largest of which are at Bass Rock (75,000 pairs as of 2014), St. Kilda (60,000 pairs as of 2013) and Ailsa Craig (33,000 pairs as of 2014) in Scotland, Grassholm in Wales, and Bonaventure Island (60,000 pairs in 2009) off the coast of Quebec. Its breeding range has extended northward and eastward, with colonies being established on Russia's Kola Peninsula in 1995 and Bear Island (the southernmost island of Svalbard), in 2011. Colonies are mostly located on offshore islands with cliffs, from which the birds can more easily launch into the air. The northern gannet undertakes seasonal migrations and catches fish (which are the mainstay of its diet) by making high-speed dives into the sea.

    The northern gannet was previously hunted for food in certain parts of its range, and although that practice still continues in the Outer Hebrides of Scotland and the Faroe Islands, the bird faces few other natural or man-made threats. Since its population is growing, the International Union for Conservation of Nature considers it a least-concern species. Because it is both a conspicuous and a common bird, it is referred to in several ancient myths and legends. (Full article...)

  • Male breeding plumage of Q. q. lathamii

    The red-billed quelea (/ˈkwiːliə/; Quelea quelea), also known as the red-billed weaver or red-billed dioch, is a small—approximately 12 cm (4.7 in) long and weighing 15–26 g (0.53–0.92 oz)—migratory, sparrow-like bird of the weaver family, Ploceidae, native to Sub-Saharan Africa.

    It was named by Linnaeus in 1758, who considered it a bunting, but Ludwig Reichenbach assigned it in 1850 to the new genus Quelea. Three subspecies are recognised, with Quelea quelea quelea occurring roughly from Senegal to Chad, Q. q. aethiopica from Sudan to Somalia and Tanzania, and Q. q. lathamii from Gabon to Mozambique and South Africa. Non-breeding birds have light underparts, striped brown upper parts, yellow-edged flight feathers and a reddish bill. Breeding females attain a yellowish bill. Breeding males have a black (or rarely white) facial mask, surrounded by a purplish, pinkish, rusty or yellowish wash on the head and breast. The species avoids forests, deserts and colder areas such as those at high altitude and in southern South Africa. It constructs oval roofed nests woven from strips of grass hanging from thorny branches, sugar cane or reeds. It breeds in very large colonies.

    The quelea feeds primarily on seeds of annual grasses, but also causes extensive damage to cereal crops. Therefore, it is sometimes called "Africa's feathered locust". The usual pest-control measures are spraying avicides or detonating fire-bombs in the enormous colonies during the night. Extensive control measures have been largely unsuccessful in limiting the quelea population. When food runs out, the species migrates to locations of recent rainfall and plentiful grass seed; hence it exploits its food source very efficiently. It is regarded as the most numerous undomesticated bird on earth, with the total post-breeding population sometimes peaking at an estimated 1.5 billion individuals. It feeds in huge flocks of millions of individuals, with birds that run out of food at the rear flying over the entire group to a fresh feeding zone at the front, creating an image of a rolling cloud. The conservation status of red-billed quelea is least concern according to the IUCN Red List. (Full article...)

  • Male (above) and female (below)

    The crescent honeyeater (Phylidonyris pyrrhopterus) is a passerine bird of the honeyeater family Meliphagidae native to southeastern Australia. A member of the genus Phylidonyris, it is most closely related to the common New Holland honeyeater (P. novaehollandiae) and the white-cheeked honeyeater (P. niger). Two subspecies are recognized, with P. p. halmaturinus restricted in range to Kangaroo Island and the Mount Lofty Ranges in South Australia.

    It has dark grey plumage and paler underparts, highlighted by yellow wing-patches and a broad, black crescent, outlined in white, down the sides of its breast. The species exhibits slight sexual dimorphism, with the female being duller in colour than the male. Juvenile birds are similar to the female, though the yellow wing-patches of male nestlings can be easily distinguished.

    The male has a complex and variable song, which is heard throughout the year. It sings from an exposed perch, and during the breeding season performs song flights. The crescent honeyeater is found in areas of dense vegetation including sclerophyll forest and alpine habitats, as well as heathland, and parks and gardens, where its diet is made up of nectar and invertebrates. It forms long-term pairs, and often stays committed to one breeding site for several years. The female builds the nest and does most of the caring for the two to three young, which become independent within 40 days of laying its egg. (Full article...)

  • Call of vermilion flycatcher

    The vermilion flycatcher (Pyrocephalus obscurus) is a small passerine bird in the tyrant flycatcher family found throughout South America and southern North America. It is a striking exception among the generally drab Tyrannidae due to its vermilion-red coloration. The males have bright red crowns, chests, and underparts, with brownish wings and tails. Females lack the vivid red coloration and can be hard to identify—they may be confused for the Say's phoebe. The vermilion flycatcher's song is a pit pit pit pidddrrrreeedrr, which is variable and important in establishing a territory. Riparian habitats and semi-open environments are preferred. As aerial insectivores, they catch their prey while flying. Their several months-long molt begins in summer.

    Despite being socially monogamous, vermilion flycatchers will engage in extra-pair copulation. They also practice within-species brood parasitism, whereby females lay their eggs in the nest of another individual. Females build shallow open cup nests and incubate the brown-speckled whitish eggs. The male feeds the female during incubation. Two broods of two or three eggs are laid in a season lasting from March through June. Once hatched, both males and females feed the chicks, which are ready to fledge after 15 days.

    The species was first described in the late 1830s as a result of the voyages of Charles Darwin. The taxonomy of the genus Pyrocephalus was revised in 2016, which led to the identification of several new species from the vermilion flycatcher's subspecies, including the now-extinct San Cristóbal flycatcher. Populations have declined because of habitat loss, though the species remains abundant. The overall population numbers are in the millions, thus the International Union for Conservation of Nature considers it a species of least concern. (Full article...)

  • In Baikonur, Kazakhstan

    The mistle thrush (Turdus viscivorus), also spelled missel thrush, is a bird common to much of Europe, temperate Asia and North Africa. It is a year-round resident in a large part of its range, but northern and eastern populations migrate south for the winter, often in small flocks. It is a large thrush with pale grey-brown upper parts, a greyish-white chin and throat, and black spots on its pale yellow and off-white under parts. The sexes are similar in plumage, and its three subspecies show only minimal differences. The male has a loud, far-carrying song which is delivered even in wet and windy weather, earning the bird the old name of stormcock.

    Found in open woods, parks, hedges and cultivated land, the mistle thrush feeds on a wide variety of invertebrates, seeds and berries. Its preferred fruits include those of the mistletoe, holly and yew. Mistletoe is favoured where it is available, and this is reflected in the thrush's English and scientific names; the plant, a parasitic species, benefits from its seeds being excreted by the thrush onto branches where they can germinate. In winter, a mistle thrush will vigorously defend mistletoe clumps or a holly tree as a food reserve for when times are hard.

    The open cup nest is built against a trunk or in a forked branch, and is fearlessly defended against potential predators, sometimes including humans or cats. The clutch, typically of three to five eggs, is incubated for 12–15 days, mainly by the female. The chicks fledge about 14–16 days after hatching. There are normally two broods. There was a range expansion in the 18th and early 19th centuries, and a small decline in recent decades, perhaps due to changes in agricultural practices. Given its high numbers and very large range, this thrush is classified by the International Union for Conservation of Nature as being of least concern. (Full article...)

  • Anthus spinoletta spinoletta

    The water pipit (Anthus spinoletta) is a small passerine bird which breeds in the mountains of Southern Europe and the Palearctic eastwards to China. It is a short-distance migrant; many birds move to lower altitudes or wet open lowlands in winter.

    The water pipit in breeding plumage has greyish-brown upperparts, weakly streaked with darker brown, and pale pink-buff underparts fading to whitish on the lower belly. The head is grey with a broad white supercilium ("eyebrow"), and the outer tail feathers are white. In winter, the head is grey-brown, the supercilium is duller, the upperparts are more streaked, and the underparts are white, streaked lightly with brown on the breast and flanks. There are only minor differences among the three subspecies, the sexes are almost identical, and young birds resemble adults. The water pipit's song is delivered from a perch or in flight, and consists of four or five blocks, each consisting of about six repetitions of a different short note.

    Water pipits construct a cup-like nest on the ground under vegetation or in cliff crevices and lay four to six speckled grey-ish white eggs, which hatch in about two weeks with a further 14–15 days to fledging. Although pipits occasionally catch insects in flight, they feed mainly on small invertebrates picked off the ground or vegetation, and also some plant material. (Full article...)

  • S. e. caesia in Central Europe
    Song recorded in Surrey, England
    Call recorded in Surrey, England

    The Eurasian nuthatch or wood nuthatch (Sitta europaea) is a small passerine bird found throughout the Palearctic and in Europe. Like other nuthatches, it is a short-tailed bird with a long bill, blue-gray upperparts and a black eye-stripe. It is a vocal bird with a repeated loud dwip call. There are more than 20 subspecies in three main groups; birds in the west of the range have orange-buff underparts and a white throat, those in Russia have whitish underparts, and those in the east have a similar appearance to European birds, but lack the white throat.

    Its preferred habitat is mature deciduous or mixed woodland with large, old trees, preferably oak. Pairs hold permanent territories, and nest in tree holes, usually old woodpecker nests, but sometimes natural cavities. If the entrance to the hole is too large, the female plasters it with mud to reduce its size, and often coats the inside of the cavity too. The six to nine red-speckled white eggs are laid on a deep base of pine or other wood chips.

    The Eurasian nuthatch eats mainly insects , particularly caterpillars and beetles, although in autumn and winter its diet is supplemented with nuts and seeds. The young are fed mainly on insects, with some seeds, food items mainly being found on tree trunks and large branches. The nuthatch can forage when descending trees head first, as well as when climbing. It readily visits bird tables, eating fatty man-made food items as well as seeds. It is an inveterate hoarder, storing food year-round. Its main natural predator is the Eurasian sparrowhawk. (Full article...)

  • Beach viewed from board-walk through the pines

    Holkham National Nature Reserve is England's largest national nature reserve (NNR). It is on the Norfolk coast between Burnham Overy Staithe and Blakeney, and is managed by Natural England with the cooperation of the Holkham Estate. Its 3,900 hectares (9,600 acres) comprise a wide range of habitats, including grazing marsh, woodland, salt marsh, sand dunes and foreshore. The reserve is part of the North Norfolk Coast Site of Special Scientific Interest, and the larger area is additionally protected through Natura 2000, Special Protection Area (SPA) and Ramsar listings, and is part of both an Area of Outstanding Natural Beauty (AONB) and a World Biosphere Reserve. Holkham NNR is important for its wintering wildfowl, especially pink-footed geese, Eurasian wigeon and brant geese, but it also has breeding waders, and attracts many migrating birds in autumn. Many scarce invertebrates and plants can be found in the dunes, and the reserve is one of the only two sites in the UK to have an antlion colony.

    This stretch of coast originally consisted of salt marshes protected from the sea by ridges of shingle and sand, and Holkham's Iron Age fort stood at the end of a sandy spit surrounded by the tidal wetland. The Vikings navigated the creeks to establish Holkham village, but access to the former harbour was stopped by drainage and reclamation of the marshes between the coast and the shingle ridge which started in the 17th century, and was completed in 1859. The Holkham estate has been owned by the Coke family, later Earls of Leicester since 1609, and their seat at Holkham Hall is opposite the reserve's Lady Anne's Drive entrance. The 3rd Earl planted pines on the dunes to protect the pastures reclaimed by his predecessors from wind-blown sand. The national nature reserve was created in 1967 from 1,700 hectares (4,200 acres) of the Holkham Estate and 2,200 hectares (5,400 acres) of foreshore belonging to the Crown.

    The reserve has over 100,000 visitors a year, including birdwatchers and horse riders, and is therefore significant for the local economy. The NNR has taken steps to control entry to the fragile dunes and other areas important for their animals or plants because of the damage to sensitive habitats that could be caused by unrestricted access. The dunes are an essential natural defence against the projected rises in sea level along this vulnerable coast. (Full article...)

  • Adult of nominate subspecies in Switzerland

    The Alpine chough (/ˈtʃʌf/, pronounced /chúf/) or yellow-billed chough (Pyrrhocorax graculus) is a bird in the crow family, one of only two species in the genus Pyrrhocorax. Its two subspecies breed in high mountains from Spain eastwards through southern Europe and North Africa to Central Asia and Nepal, and it may nest at a higher altitude than any other bird. The eggs have adaptations to the thin atmosphere that improve oxygen take-up and reduce water loss.

    This bird has glossy black plumage, a yellow beak, red legs, and distinctive calls. It has a buoyant acrobatic flight with widely spread flight feathers. The Alpine chough pairs for life and displays fidelity to its breeding site, which is usually a cave or crevice in a cliff face. It builds a lined stick nest and lays three to five brown-blotched whitish eggs. It feeds, usually in flocks, on short grazed grassland, taking mainly invertebrate prey in summer and fruit in winter; it will readily approach tourist sites to find supplementary food.

    Although it is subject to predation and parasitism, and changes in agricultural practices have caused local population declines, this widespread and abundant species is not threatened globally. Climate change may present a long-term threat, by shifting the necessary Alpine habitat to higher altitudes. (Full article...)

  • The letter-winged kite (Elanus scriptus) is a small, rare and irruptive bird of prey that is found only in Australia. Measuring around 35 cm (14 in) in length with a wingspan of 84–100 cm (33–39 in), the adult letter-winged kite has predominantly pale grey and white plumage and prominent black rings around its red eyes. Its name derives from its highly distinctive black underwing pattern of a shallow 'M' or 'W' shape, visible when in flight. This distinguishes it from the otherwise similar black-shouldered kite. This species is also the only nocturnal species within the order Accipitriformes despite few differences found in its visual anatomy to other closely related kites.

    The species begins breeding in response to rodent outbreaks, with pairs nesting in loose colonies of up to 50 birds each. Three to four eggs are laid and incubated for around thirty days, though the eggs may be abandoned if the food source disappears. Chicks are fledged within five weeks of hatching. Roosting in well-foliaged trees during the day, the letter-winged kite hunts mostly at night. It is a specialist predator of rodents, which it hunts by hovering above grasslands and fields. It is rated as near threatened on the International Union for Conservation of Nature (IUCN)'s Red List of Threatened Species. (Full article...)

  • Reconstructed skeleton, Florida Museum of Natural History

    Titanis (meaning "Titan" for the mythological Greek Titans) is a genus of phorusrhacid ("terror birds", a group originating in South America), an extinct family of large, predatory birds, in the order Cariamiformes that inhabited the United States during the Pliocene and earliest Pleistocene. The first fossils were unearthed by amateur archaeologists Benjamin Waller and Robert Allen from the Santa Fe River in Florida and were named Titanis walleri by ornithologist Pierce Brodkorb in 1963, the species name honoring Waller. The holotype material is fragmentary, consisting of only an incomplete right tarsometatarsus (lower leg bone) and phalanx (toe bone), but comes from one of the largest phorusrhacid individuals known. In the years following the description, many more isolated elements have been unearthed from sites from other areas of Florida, Texas, and California. It was classified in the subfamily Phorusrhacinae, which includes some of the last and largest phorusrhacids like Devincenzia and Kelenken.

    Like all phorusrhacids, Titanis had elongated hind limbs, a thin pelvis, proportionally small wings, and a large skull with a hooked beak. It was one of the largest phorusrhacids, possibly similar in size to Phorusrhacos based on preserved material. More recent estimates placed Titanis at 1.4 to 2 meters (4.6 to 6.6 ft) in height and 150 kilograms (330 lb) in body mass. Due to the fragmentary fossils, the anatomy is poorly known, but several distinct characters on the tarsometatarsus have been observed. The skull is estimated to have been between 36 centimetres (14 in) and 56 centimetres (22 in) in length, one of the largest known from any bird.

    Phorusrhacids are thought to have been ground predators or scavengers, and have often been considered apex predators that dominated Cenozoic South America in the absence of placental mammalian predators, though they did co-exist with some large, carnivorous borhyaenid mammals. Titanis co-existed with many placental predators in North America and was likely one of several apex predators in its ecosystem. The tarsometatarsus was long and slender, like that of its relative Kelenken, which has been suggested to have been agile and capable of running at high speeds. Studies of the related Andalgalornis show that large phorusrhacids had very stiff and stress-resistant skulls; this indicates they may have swallowed small prey whole or targeted larger prey with repetitive strikes of the beak. Titanis is known from the Pliocene deposits of Florida, southern California, and southeastern Texas, regions that had large open savannas and a menagerie of mammalian megafauna. It likely preyed on mammals such as the extinct armadillo relatives Holmesina and Glyptotherium, equids, tapirs, capybaras, and other Pliocene herbivores. Titanis is unique among phorusrhacids in that it is the only one known from North America, crossing over from South America during the Great American Interchange. (Full article...)

  • Adult and juvenile specimens, Muséum national d'Histoire naturelle, Paris; the juvenile could possibly also be from Kangaroo Island

    The King Island emu (Dromaius novaehollandiae minor) is an extinct subspecies of emu that was endemic to King Island, in the Bass Strait between mainland Australia and Tasmania. Its closest relative may be the also extinct Tasmanian emu (D. n. diemenensis), as they belonged to a single population until less than 14,000 years ago, when Tasmania and King Island were still connected. The small size of the King Island emu may be an example of insular dwarfism. The King Island emu was the smallest of all known emus and had darker plumage than the mainland emu. It was black and brown and had naked blue skin on the neck, and its chicks were striped like those on the mainland. The subspecies was distinct from the likewise small and extinct Kangaroo Island emu (D. n. baudinianus) in a number of osteological details, including size. The behaviour of the King Island emu probably did not differ much from that of the mainland emu. The birds gathered in flocks to forage and during breeding time. They fed on berries, grass and seaweed. They ran swiftly and could defend themselves by kicking. The nest was shallow and consisted of dead leaves and moss. Seven to nine eggs were laid, which were incubated by both parents.

    Europeans discovered the King Island emu in 1802 during early expeditions to the island, and most of what is known about the bird in life comes from an interview French naturalist François Péron conducted with a sealer there, as well as depictions by artist Charles Alexandre Lesueur. They had arrived on King Island in 1802 with Nicolas Baudin's expedition, and in 1804 several live and stuffed King and Kangaroo Island emus were sent to France. The two live King Island specimens were kept in the Jardin des Plantes, and the remains of these and the other birds are scattered throughout various museums in Europe today. The logbooks of the expedition did not specify from which island each captured bird originated, or even that they were taxonomically distinct, so their status remained unclear until more than a century later. Hunting pressure and fires started by early settlers on King Island likely drove the wild population to extinction by 1805. The captive specimens in Paris both died in 1822 and are believed to have been the last of their kind. (Full article...)

  • The only specimen in existence today

    The spotted green pigeon or Liverpool pigeon (Caloenas maculata) is a species of pigeon which is most likely extinct. It was first mentioned and described in 1783 by John Latham, who had seen two specimens of unknown provenance and a drawing depicting the bird. The taxonomic relationships of the bird were long obscure, and early writers suggested many different possibilities, though the idea that it was related to the Nicobar pigeon (C. nicobarica) prevailed, and it was therefore placed in the same genus, Caloenas. Today, the species is only known from a specimen kept in World Museum, Liverpool. Overlooked for much of the 20th century, it was recognised as a valid extinct species by the IUCN Red List only in 2008. It may have been native to an island somewhere in the South Pacific Ocean or the Indian Ocean, and it has been suggested that a bird referred to as titi by Tahitian islanders was this bird. In 2014, a genetic study confirmed it as a distinct species related to the Nicobar pigeon, and showed that the two were the closest relatives of the extinct dodo and Rodrigues solitaire.

    The surviving specimen is 32 cm (13 in) long, and has very dark, brownish plumage with a green gloss. The neck feathers are elongated, and most of the feathers on the upperparts and wings have a yellowish spot on their tips. It has a black bill with a yellow tip, and the end of the tail has a pale band. It has relatively short legs and long wings. It has been suggested it had a knob on its bill, but there is no evidence for this. Unlike the Nicobar pigeon, which is mainly terrestrial, the physical features of the spotted green pigeon suggest it was mainly arboreal, and fed on fruits. The spotted green pigeon may have been close to extinction by the time Europeans arrived in its native area, and may have disappeared due to over-hunting and predation by introduced animals around the 1820s. (Full article...)

Tema general de aves seleccionado

Nido de copa profunda del carricero común

Un nido de pájaro es el lugar en el que un pájaro pone e incuba sus huevos y cría a sus crías. Aunque el término se refiere popularmente a una estructura específica hecha por el propio ave, como el nido cubierto de hierba del petirrojo americano o el mirlo euroasiático , o el nido colgante elaboradamente tejido de la oropéndola Moctezuma o el tejedor de aldea , se trata de una definición demasiado restrictiva. . Para algunas especies, un nido es simplemente una depresión poco profunda hecha en arena; para otros, es el agujero dejado por una rama rota, una madriguera excavada en la tierra, una cámara excavada en un árbol, un enorme montón de vegetación y tierra en descomposición, una plataforma hecha de saliva seca o una cúpula de barro con una túnel de entrada. Los nidos de pájaros más pequeños son los de algunos colibríes , copas diminutas que pueden medir apenas 2 cm (0,8 pulgadas) de ancho y 2 a 3 cm (0,8 a 1,2 pulgadas) de alto. En el otro extremo, algunos montículos de nidos construidos por el matorral oscuro miden más de 11 m (36 pies) de diámetro y casi 5 m (16 pies) de altura. El estudio de los nidos de las aves se conoce como caliología .

No todas las especies de aves construyen nidos. Algunas especies ponen sus huevos directamente en el suelo o en salientes rocosos, mientras que los parásitos de cría ponen los suyos en los nidos de otras aves, dejando que "padres adoptivos" involuntarios hagan el trabajo de criar a las crías. Aunque los nidos se utilizan principalmente para la reproducción, también se pueden reutilizar en la temporada no reproductiva para descansar y algunas especies construyen nidos de dormitorio especiales o nidos de descanso (o nidos de invierno ) que se utilizan sólo para dormir. La mayoría de las aves construyen un nido nuevo cada año, aunque algunas renuevan sus nidos viejos. Los grandes nidos (o nidos ) de algunas águilas son nidos en plataformas que han sido utilizados y renovados durante varios años. ( Articulo completo... )

Taxón seleccionado

Papamoscas pizarroso de ojos blancos ,
( Melaenornis fischeri )
Los papamoscas del Viejo Mundo son una gran familia, los Muscicapidae , de pequeñas aves paseriformes restringidas al Viejo Mundo ( Europa , África y Asia ), con la excepción de varios vagabundos y dos especies, el pechiazul ( Luscinia svecica ) y la collalba gris ( Oenanthe oenanthe). ), que se encuentra también en América del Norte. Se trata principalmente de pequeños insectívoros arbóreos , muchos de los cuales, como su nombre indica, capturan a sus presas al vuelo. La familia es relativamente grande e incluye 351 especies que se dividen en 54 géneros . ( Articulo completo... )
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Temas

Anatomía: Anatomía  • Esqueleto  • Vuelo  • Huevos  • Plumas  • Plumaje   

Evolución y extinción: Evolución  • Archaeopteryx  • Hibridación  • Aves prehistóricas del Cuaternario tardío  • Fósiles  • Taxonomía  • Extinción   

Comportamiento: Canto  • Inteligencia  • Migración  • Reproducción  • Anidación  • Incubación  • Parásitos de cría   

Órdenes de aves :  Struthioniformes •  Tinamiformes •  Anseriformes •  Accipitriformes •  Galliformes •  Gaviiformes •  Podicipediformes •  Procellariiformes •  Sphenisciformes •  Pelecaniformes •  Ciconiiformes •  Phoenicopteriformes •  Falconiformes •  Gruiformes •  Charadriiformes •  Pteroclidiformes •  Columbiformes •  Psittaciformes •  • Strigiformes  • Caprimulgiformes  • Apodiformes  • Coraciiformes  • Piciformes  • Trogoniformes  • Coliiformes  • Passeriformes   

Listas de aves: Familias y órdenes  • Listas por región   

Aves y humanos: Anillamiento  • Ornitología  • Colecciones de aves  • Observación de aves  • Alimentación de aves  • Conservación  • Avicultura   

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Citas

--Mark Twain , [1]

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Recursos

Recursos gratuitos en línea:

  • SORA: The Searchable Online Research Archive (SORA) tiene décadas de archivos de las siguientes revistas: The Auk , The Condor , Journal of Field Ornithology , North American Bird Bander , Studies in Avian Biology , Pacific Coast Avifauna y The Wilson Bulletin . La cobertura finaliza alrededor del año 2000. La posibilidad de buscar en todas las revistas o navegar existe en la página principal.
  • Notornis: la Revista de la Sociedad de Ornitología de Nueva Zelanda cubre Nueva Zelanda y el Pacífico Sur.
  • New Zealand Journal of Ecology : esta revista publica a menudo artículos relacionados con las aves. Al igual que Notornis , esta revista se ocupa de Nueva Zelanda y sus alrededores.
  • Ornitología Marina : Publicada por numerosos grupos de investigación de aves marinas, Ornitología Marina es específica y se remonta a muchos años atrás.
  • BirdLife International: La zona de datos tiene cuentas de especies para cada especie, aunque las especies amenazadas y algunos grupos clave tienen mayor detalle y otras solo tienen estado y evaluación.
  • Índice de autores: esta es una buena fuente de autoridades binomiales para taxoboxes.

También está Birds of North America, el proyecto masivo de la Universidad de Cornell que recopila información sobre todas las aves reproductoras en el área de ABA. Está disponible por 40 dólares al año.

Para obtener más fuentes, incluidas fuentes impresas, consulte WikiProject Birds .

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WikiProyectos

Imágenes seleccionadas

Tema seleccionado de anatomía de aves.

El proventrículo forma parte del sistema digestivo de las aves . Un órgano análogo existe en invertebrados e insectos . ( Articulo completo... )
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Especies seleccionadas

Un espléndido reyezuelo macho (subsp. splendens)
El reyezuelo espléndido ( Malurus splendens ), también conocido simplemente como reyezuelo espléndido o más coloquialmente en Australia Occidental como reyezuelo azul , es un ave paseriforme de la familia Maluridae . Se encuentra en gran parte del continente australiano, desde el centro-oeste de Nueva Gales del Sur y el suroeste de Queensland hasta la costa de Australia Occidental. El macho en plumaje nupcial es un ave pequeña, de cola larga, de coloración predominantemente azul brillante y negra. Los machos, las hembras y los juveniles no reproductores son predominantemente de color marrón grisáceo. Comprende varias subespecies similares, completamente azules y negras, que originalmente se consideraban especies separadas. Al igual que otros reyezuelos, el espléndido reyezuelo se destaca por varias características de comportamiento peculiares; Las aves son socialmente monógamas y sexualmente promiscuas . Los reyezuelos machos arrancan pétalos rosados ​​o morados y se los muestran a las hembras como parte de una exhibición de cortejo. El hábitat del espléndido reyezuelo varía desde el bosque hasta el matorral seco, generalmente con abundante vegetación como refugio. No se ha adaptado bien a la ocupación humana del paisaje y ha desaparecido de algunas zonas urbanizadas. El espléndido reyezuelo se alimenta principalmente de insectos y complementa su dieta con semillas.


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Sabías

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Categorías

rompecabezas de categoría
rompecabezas de categoría
Aves
Aves por clasificación
Aves por ubicación
Aves por año de descripción formal.
Aves individuales
Listas de aves
Aves y humanos
Anatomía de las aves
Comportamiento de las aves
Nombres comunes de aves
Redirecciones de aves
Aves por adaptación
Colores de pájaros
Conservación de aves
Ecología de aves
Evolución de las aves
Aves no voladoras
Hibridación en aves.
imagenes de pajaros
Aves introducidas
Mortalidad de aves
Aves prehistóricas
Taxonomía de aves
Aves de trabajo
Trozos de pájaros
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Portales relacionados

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Cosas que puedes hacer

Crear artículos solicitados (WikiProject Birds – Solicitudes de artículos):

Haz estas tareas:

Tareas más destacadas en la lista de limpieza del proyecto, Categoría: artículos sobre aves que necesitan atención y Wikipedia: WikiProject Birds/Todo .

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Taxonomía de Aves

Wikimedia asociada

Los siguientes proyectos hermanos de la Fundación Wikimedia brindan más información sobre este tema:


  • Repositorio multimedia gratuito Commons
  • Wikilibros
    Libros de texto y manuales gratuitos

  • Base de conocimientos gratuita de Wikidata
  • Wikinoticias
    Noticias de contenido libre
  • Wikiquote
    Colección de citas

  • Biblioteca de contenido gratuito de Wikisource
  • Wikispecies
    Directorio de especies
  • Wikiversidad
    Herramientas de aprendizaje gratuitas
  • Wikivoyage
    Guía de viaje gratuita

  • Diccionario y tesauro de Wikcionario

Fuentes

  1. ^ kleiser, G. (2005). Diccionario de proverbios. Corporación Editorial APH. pag. 283.ISBN​ 978-81-7648-814-3. Consultado el 7 de febrero de 2020 .
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