Great egret | |
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Adult in breeding plumage in Cape May County, New Jersey | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Ardeidae |
Genus: | Ardea |
Species: | A. alba |
Binomial name | |
Ardea alba | |
Range of A. alba (excluding A. a. modesta ) Breeding range Year-round range Wintering range | |
Synonyms | |
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The great egret (Ardea alba), also known as the common egret, large egret, or (in the Old World) great white egret [2] or great white heron, [3] [4] [5] is a large, widely distributed egret. The four subspecies are found in Asia, Africa, the Americas, and southern Europe. Recently, it has also been spreading to more northern areas of Europe. Distributed across most of the tropical and warmer temperate regions of the world, it builds tree nests in colonies close to water.
The great egret was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae under the binomial name Ardea alba. He specified the type locality as Europe. [6] [7] The scientific name comes from Latin ardea, "heron", and alba, "white". [8]
Like all egrets, it is a member of the heron family, Ardeidae. Traditionally classified with the storks in the Ciconiiformes, the Ardeidae are closer relatives of pelicans and belong in the Pelecaniformes, instead. The great egret—unlike the typical egrets—does not belong to the genus Egretta , but together with the great herons is today placed in Ardea . In the past, however, it was sometimes placed in Egretta or separated in a monotypic genus Casmerodius.
The Old World population is often referred to as the "great white egret". This species is sometimes confused with the great white heron of the Caribbean, which is a white morph of the closely related great blue heron.
Four subspecies are found in various parts of the world, which differ but little. [9] Differences among them include bare-part coloration in the breeding season and size. The smallest subspecies, A. a. modesta, is from Asia and Australasia and some taxonomists consider it to be a full species, the eastern great egret (Ardea modesta), but most scientists treat it as a subspecies. [9]
The great egret is a large heron with all-white plumage. Standing up to 1 m (3.3 ft) tall, this species can measure 80 to 104 cm (31 to 41 in) in length with a wingspan of 131 to 170 cm (52 to 67 in). [10] [11] Body mass can range from 700 to 1,500 g (1.5 to 3.3 lb), with an average around 1,000 g (2.2 lb). [12] It is thus only slightly smaller than the great blue or grey heron (A. cinerea). Apart from size, the great egret can be distinguished from other white egrets by its yellow bill and black legs and feet, though the bill may become darker and the lower legs lighter in the breeding season. In breeding plumage, delicate ornamental feathers are borne on the back. Males and females are identical in appearance; juveniles look like nonbreeding adults. Differentiated from the intermediate egret (Ardea intermedia) by the gape, which extends well beyond the back of the eye in case of the great egret, but ends just behind the eye in case of the intermediate egret.
Its flight is slow with its neck retracted. This is characteristic of herons and bitterns, and distinguishes them from storks, cranes, ibises, and spoonbills, which extend their necks in flight. The great egret walks with its neck extended and wings held close. The great egret is not normally a vocal bird; it gives a low, hoarse croak when disturbed, and at breeding colonies, it often gives a loud croaking cuk cuk cuk and higher-pitched squawks. [13]
Owing to its wide distribution across so much of the Americas, as well as Africa, Europe and Asia, the great egret shares its habitat with many other similar species. For example, the little egret (Egretta garzetta), intermediate egret (Ardea intermedia), Chinese egret (Egretta eulophotes), and the western reef heron (Egretta gularis). In the Americas, the snowy egret (Egretta thula)—a medium-sized heron that shares the same habitat as the great egret—is one such species. The snowy egret is readily distinguished from the great egret because it is noticeably smaller, and it has a more slender bill which is black in color and yellow feet, whereas the great egret has a yellow bill and black feet. Another species that—in North America—is easily confused with the great egret is the white morph of the great blue heron (Ardea herodias). The great blue heron is a bit larger, and has a thicker bill than that of the great egret. [14]
The great egret is generally a very successful species with a large and expanding range, occurring worldwide in temperate and tropical habitats. It is ubiquitous across the Sun Belt of the United States and in the Neotropics. [1]
In North America, large numbers of great egrets were killed around the end of the 19th century so that their plumes, known as "aigrettes", could be used to decorate hats. [15] [16] Numbers have since recovered as a result of conservation measures. Its range has expanded as far north as southern Canada. However, in some parts of the southern United States, its numbers have declined due to habitat loss, particularly wetland degradation through drainage, grazing, clearing, burning, increased salinity, groundwater extraction and invasion by exotic plants. Nevertheless, the species adapts well to human habitation and can be readily seen near wetlands and bodies of water in urban and suburban areas. [1]
The great egret is partially migratory, with northern hemisphere birds moving south from areas with colder winters. It is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.[ citation needed ]
In 1953, the great egret in flight was chosen as the symbol of the National Audubon Society, which was formed in part to prevent the killing of birds for their feathers. [17] [18]
On 22 May 2012, a pair of great egrets was observed nesting in the UK for the first time at the Shapwick Heath nature reserve in Somerset. [19] The species was a rare visitor to the UK and Ben Aviss of the BBC stated that the news could mean the UK's first great egret colony had become established. [19] [20] The following week, Kevin Anderson of Natural England confirmed a great egret chick had hatched, making it a new breeding bird record for the UK. [21] In 2017, seven nests in Somerset fledged 17 young, [22] and a second breeding site was announced at Holkham National Nature Reserve in Norfolk where a pair fledged three young. [23] In January 2021, BirdGuides, a UK website and magazine which reports sightings of rare birds, dropped the species from its list of nationally rare birds because sightings had become so numerous. [24] In August 2024, RSPB Scotland announced that a pair had raised three chicks at their Loch of Strathbeg nature reserve in North Aberdeenshire, the first chicks to hatch in Scotland. [25]
A similar move northwards has been observed in the Nordic countries where historically it was only a rare visitor. The first confirmed breeding in Sweden was 2012 and in Denmark was 2014. Both countries now have small colonies. [26] [27] In 2018, a pair of great egrets nested in Finland for the first time, raising four young in a grey heron colony in Porvoo. [28]
The species breeds in colonies in trees close to large lakes with reed beds or other extensive wetlands, preferably at height of 10–40 feet (3.0–12.2 m). [13] It begins to breed at 2–3 years of age by forming monogamous pairs each season. Whether the pairing carries over to the next season is not known. The male selects the nest area, starts a nest, and then attracts a female. The nest, made of sticks and lined with plant material, could be up to 3 feet across. Up to six bluish green eggs are laid at one time. Both sexes incubate the eggs, and the incubation period is 23–26 days. The young are fed by regurgitation by both parents and are able to fly within 6–7 weeks. [29]
The great egret forages in shallow water or in drier habitats, feeding mainly on fish, frogs, other amphibians, [30] small mammals (such as mice), [31] and occasionally small reptiles (such as snakes), [31] crustaceans (such as crayfish) [32] and insects (such as crickets and grasshoppers). [31] This species normally impales its prey with its long, sharp bill by standing still and allowing the prey to come within the striking distance of its bill, which it uses as a spear. It often waits motionless for prey or slowly stalks its victim.
A long-running field study (1962–2013) suggested that the great egrets of central Europe host 17 different helminth species. Juvenile great egrets were shown to host fewer species, but the intensity of infection was higher in the juveniles than in the adults. Of the digeneans found in central European great egrets, numerous species likely infected their definitive hosts outside of central Europe itself. [33]
The great egret is depicted on the reverse side of a 5-Brazilian reais banknote. [34]
The great egret is the symbol of the National Audubon Society. [35]
An airbrushed photograph of a great egret in breeding plumage by Werner Krutein is featured in the cover art of the 1992 Faith No More album Angel Dust . [36]
In Belarus, a commemorative coin has the image of a great egret. [37] The great egret also features on the New Zealand $2 coin and on the Hungarian 5-forint coin. [38]
Egrets are herons, generally long-legged wading birds, that have white or buff plumage, developing fine plumes during the breeding season. Egrets are not a biologically distinct group from herons and have the same build.
The great blue heron is a large wading bird in the heron family Ardeidae, common near the shores of open water and in wetlands over most of North and Central America, as well as far northwestern South America, the Caribbean and the Galápagos Islands. It is occasionally found in the Azores and is a rare vagrant to Europe. An all-white population found in south Florida and the Florida Keys is known as the great white heron. Debate exists about whether these white birds are a color morph of the great blue heron, a subspecies of it, or an entirely separate species.
Herons are long-legged, long-necked, freshwater and coastal birds in the family Ardeidae, with 72 recognised species, some of which are referred to as egrets or bitterns rather than herons. Members of the genera Botaurus and Ixobrychus are referred to as bitterns, and, together with the zigzag heron, or zigzag bittern, in the monotypic genus Zebrilus, form a monophyletic group within the Ardeidae. Egrets do not form a biologically distinct group from herons, and tend to be named differently because they are mainly white or have decorative plumes in breeding plumage. Herons, by evolutionary adaptation, have long beaks.
The grey heron is a long-legged wading bird of the heron family, Ardeidae, native throughout temperate Europe and Asia, and also parts of Africa. It is resident in much of its range, but some populations from the more northern parts migrate southwards in autumn. A bird of wetland areas, it can be seen around lakes, rivers, ponds, marshes and on the sea coast. It feeds mostly on aquatic creatures which it catches after standing stationary beside or in the water, or stalking its prey through the shallows.
The yellow-crowned night heron, is one of two species of night heron in genus Nyctanassa. Unlike the black-crowned night heron, which has a worldwide distribution, the yellow-crowned is restricted to the Americas. It is known as the bihoreau violacé in French and the pedrete corona clara or yaboa común in some Spanish-speaking countries.
The black-crowned night heron [or black-capped night heron], commonly shortened to just night heron in Eurasia, is a medium-sized heron found throughout a large part of the world, including parts of Europe, Asia, and North and South America. In Australasia it is replaced by the closely related Nankeen night heron, with which it has hybridised in the area of contact.
The snowy egret is a small white heron. The genus name comes from Provençal French for the little egret, aigrette, which is a diminutive of aigron, 'heron'. The species name thula is the Araucano term for the black-necked swan, applied to this species in error by Chilean naturalist Juan Ignacio Molina in 1782.
The little egret is a species of small heron in the family Ardeidae. It is a white bird with a slender black beak, long black legs and, in the western race, yellow feet. As an aquatic bird, it feeds in shallow water and on land, consuming a variety of small creatures. It breeds colonially, often with other species of water birds, making a platform nest of sticks in a tree, bush or reed bed. A clutch of three to five bluish-green eggs is laid and incubated by both parents for about three weeks. The young fledge at about six weeks of age.
The cattle egret (Bubulcus) is a cosmopolitan genus of heron found in the tropics, subtropics, and warm-temperate zones. According to the IOC bird list, it contains two species, the western cattle egret and the eastern cattle egret, although some authorities regard them as a single species. Despite the similarities in plumage to the egrets of the genus Egretta, it is more closely related to the herons of Ardea. Originally native to parts of Asia, Africa, and Europe, it has undergone a rapid expansion in its distribution and successfully colonised much of the rest of the world in the last century.
The western reef heron, also called the western reef egret, is a medium-sized heron found in southern Europe, Africa and parts of Asia. It has a mainly coastal distribution and occurs in several plumage forms: a slaty-grey plumage in which it can only be confused with the rather uncommon dark morph of the Little egret ; a white form which can look very similar to the little egret although the bill tends to be paler and larger and the black form with white throat E. g. gularis of West Africa. There are also differences in size, structure and foraging behaviour. There have been suggestions that the species hybridizes with the Little Egret, and based on this, some authors treat schistacea and gularis as subspecies of Egretta garzetta. Works that consider the Western Reef Heron as a valid species include the nominate gularis and schistacea as subspecies.
The white-faced heron also known as the white-fronted heron, and incorrectly as the grey heron, or blue crane, is a common bird throughout most of Australasia, including New Guinea, the islands of Torres Strait, Indonesia, New Zealand, and all but the driest areas of Australia.
The reddish egret is a medium-sized heron that is a resident breeder in Central America, the Bahamas, the Caribbean, the Gulf Coast of the United States, and Mexico. The egret is known for its unusual foraging behavior compared to other herons as well as its association with mud flats, its habitat of choice.
The tricolored heron, formerly known as the Louisiana heron, is a small species of heron native to coastal parts of the Americas. The species is more solitary than other species of heron in the Americas and eats a diet consisting mostly of small fish.
The little blue heron is a small heron of the genus Egretta. It is a small, darkly colored heron with a two-toned bill. Juveniles are entirely white, bearing resemblance to the snowy egret. During the breeding season, adults develop different coloration on the head, legs, and feet.
The medium egret, median egret, smaller egret or intermediate egret, is a medium-sized heron. Some taxonomists put the species in the genus Egretta or Mesophoyx. It is a resident breeder in southern and eastern Asia.
Egretta is a genus of medium-sized herons, mostly breeding in warmer climates.
The capped heron is a water bird endemic to the neotropics, inhabiting rainforest from the center of Panama to the south of Brazil. It is the only species of the genus Pilherodius, and one of the least known of the heron family, Ardeidae. It is superficially similar to the group of the night herons, but is active during daytime or at twilight.
The eastern great egret is a species of heron from the genus Ardea, usually considered a subspecies of the great egret. In New Zealand it is known as the white heron or by its Māori name kōtuku. It was first described by British ornithologist John Edward Gray in 1831.
The eastern cattle egret is a species of heron found in the tropics, subtropics and warm temperate zones. Formerly, most taxonomic authorities lumped this species and the western cattle egret together, but the two cattle egrets are now treated as separate species. Despite the similarities in plumage to the egrets of the genus Egretta, it is more closely related to the herons of Ardea. It is native to southern and eastern Asia, and Australasia.
The western cattle egret is a species of heron found in the tropics, subtropics and warm temperate zones. Formerly, most taxonomic authorities lumped this species and the eastern cattle egret together, but the two cattle egrets are now treated as separate species. Despite the similarities in plumage to the egrets of the genus Egretta, it is more closely related to the herons of Ardea. Originally native to parts of Asia, Africa and Europe, it has undergone a rapid expansion in its distribution and successfully colonised much of the rest of the world in the last century.
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