Black-crowned night heron | |
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At a rookery in Cape May County, New Jersey | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Ardeidae |
Genus: | Nycticorax |
Species: | N. nycticorax |
Binomial name | |
Nycticorax nycticorax | |
Range of N. nycticorax Breeding range Year-round range Wintering range | |
Synonyms | |
Ardea nycticoraxLinnaeus, 1758 |
The black-crowned night heron (Nycticorax nycticorax) [or black-capped night heron[ citation needed ]], 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 (N. caledonicus), with which it has hybridised in the area of contact.
The black-crowned night heron was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae . He placed it with herons, cranes and egrets in the genus Ardea and coined the binomial name Ardea nycticorax, based on specimens from southern Europe. [2] It is now placed in the genus Nycticorax that was described in 1817 by the English naturalist Thomas Forster for this species. [3] [4] The epithet nycticorax is from Ancient Greek and combines nux, nuktos meaning "night" and korax meaning "raven". The word was used by authors such as Aristotle and Hesychius of Miletus for a "bird of ill omen", perhaps an owl. The word was used by the Swiss naturalist Conrad Gessner in 1555 and then by subsequent authors for a black-crowned night heron. [5] [6]
Four subspecies are accepted: [4]
In the Falkland Islands, the bird is called quark, which is an onomatopoeia similar to its name in many other languages, like qua-bird in English, kwak in Dutch and West Frisian, kvakoš noční in Czech, квак in Ukrainian, кваква in Russian, vạc in Vietnamese, kowak-malam in Indonesian, and waqwa in Quechua.
Adults have a black crown and back with the remainder of the body white or grey, red eyes, and short yellow legs. They have pale grey wings and white under parts. One to eight (mostly two to four) long slender white plumes, erected in greeting and courtship displays, extend from the back of the head. The sexes are similar in appearance although the males are slightly larger. Black-crowned night herons do not fit the typical body form of the heron family. They are relatively stocky with shorter bills, legs, and necks than their more familiar cousins, the egrets and "day" herons. Their resting posture is normally somewhat hunched but when hunting they extend their necks and look more like other wading birds. For a short period during courtship at the start of the nesting season, the legs of adults turn bright salmon-pink, and the bare skin around the eyes blue. [7] [8]
The subspecies differ little; nominate N. n. nycticorax and N. n. hoactli are particularly similar in plumage (some authors have considered N. n. hoactli a synonym of the nominate [8] ), but the latter is on average slightly larger. N. n obscurus is the most distinctive subspecies, clearly darker than N. n. hoactli from further north in South America, but N. n. falklandicus is intermediate, with both paler and darker individuals occurring. [8]
Immature birds have dull grey-brown plumage on their heads, wings, and backs, with numerous pale "teardrop" spots. Their underparts are paler and streaked with brown. Second and third year birds attain plumages increasingly similar to adults, but lacking the white head plumes. [7] The young birds have orange eyes and duller yellowish-green legs. They are very noisy birds in their nesting colonies, with calls that are commonly transcribed as quok or woc.
Measurements:
The breeding habitat is fresh and salt-water wetlands throughout much of the world. The nominate subspecies N. n. nycticorax breeds in Europe, Asia and Africa, subspecies N. n. hoactli in North and South America from Canada as far south as northern Argentina and Chile, N. n. obscurus in southernmost South America, and N. n. falklandicus in the Falkland Islands. Black-crowned night herons nest in colonies on platforms of sticks in a group of trees, or on the ground in protected locations such as islands or reedbeds. Three to eight eggs are laid.
This heron is migratory in the northern parts of its range, but is otherwise resident (even in the cold Patagonia). European birds winter in Africa (with a few staying in southern Spain), central and east Asian birds winter in southern Asia, and North American birds winters in Mexico, the southern United States, Central America, and the West Indies.
A colony of the herons has regularly summered at the National Zoo in Washington, D.C. for more than a century. [10] The birds also prominently live year-round in the shores around the San Francisco Bay, with the largest rookery in Oakland. [11] Their ever presence at Oakland's Lake Merritt and throughout the city's downtown area, as well as their resilience to the urban environment and displacement efforts, have led to them being named Oakland's official city bird. [11]
There are two archaeological specimens of the black-crowned night heron in Great Britain. The oldest is from the Roman London Wall and the more recent from the Royal Navy's late medieval victualling yards in Greenwich. [12] It appears in the London poulterers' price lists as the Brewe, a bird which was thought to have been the Eurasian whimbrel or glossy ibis, which has now been shown to refer to the black-crowned night heron, derived from the medieval French Bihoreau. [13] Black-crowned night heron may have bred in the far wetter and wider landscape of pre-modern Britain. They were certainly imported for the table so the bone specimens themselves do not prove they were part of the British avifauna. In modern times the black-crowned night heron is a vagrant (excluding the feral breeding colonies that were established at Edinburgh Zoo from 1950 into the start of the 21st century [14] and at Great Witchingham in Norfolk, where there were 8 pairs in 2003 but breeding was not repeated subsequently [15] ). A pair of adults were seen with two recently fledged juveniles in Somerset in 2017, which is the first proven breeding record of wild black-crowned night herons in Great Britain. [16]
These birds stand still at the water's edge and wait to ambush prey, mainly at night, early morning or evening. They primarily eat small fish, leeches, earthworms, mussels, squid, [17] crustaceans (such as crayfish), [17] frogs, other amphibians, [17] aquatic insects, terrestrial insects, lizards, snakes, [17] small mammals (such as rodents), [17] small birds, eggs, carrion, plant material, and garbage and refuse at landfills. [17] They are among the seven heron species observed to engage in bait fishing; luring or distracting fish by tossing edible or inedible buoyant objects into water within their striking range – a rare example of tool use among birds. [18] [19] During the day they rest in dense trees or bushes. N. n. hoactli is more gregarious outside the breeding season than the nominate race.[ citation needed ]
A thorough study performed by J. Sitko and P. Heneberg in the Czech Republic in 1962–2013 suggested that the central European black-crowned night herons host 8 helminth species. The dominant species consisted of Neogryporhynchus cheilancristrotus (62% prevalence), Contracaecum microcephalum (55% prevalence) and Opistorchis longissimus (10% prevalence). The mean number of helminth species recorded per host individual reached 1.41. In Ukraine, other helminth species are often found in black-crowned night herons too, including Echinochasmus beleocephalus , Echinochasmus ruficapensis , Clinostomum complanatum and Posthodiplostomum cuticola . [20]
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.
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 great egret (Ardea alba), also known as the common egret, large egret, or great white egret or great white heron, 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 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 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 little bittern is a wading bird in the heron family, Ardeidae. This species was formerly placed in the genus Ixobrychus.
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 little cormorant is a member of the cormorant family of seabirds. Slightly smaller than the Indian cormorant it lacks a peaked head and has a shorter beak. It is widely distributed across the Indian Subcontinent and extends east to Java, where it is sometimes called the Javanese cormorant. It forages singly or sometimes in loose groups in lowland freshwater bodies, including small ponds, large lakes, streams and sometimes coastal estuaries. Like other cormorants, it is often found perched on a waterside rock with its wings spread out after coming out of the water. The entire body is black in the breeding season but the plumage is brownish, and the throat has a small whitish patch in the non-breeding season. These birds breed gregariously in trees, often joining other waterbirds at heronries.
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 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.
The roseate spoonbill is a gregarious wading bird of the ibis and spoonbill family, Threskiornithidae. It is a resident breeder in both South and North America. The roseate spoonbill's pink color is diet-derived, consisting of the carotenoid pigment canthaxanthin, like the American flamingo.
The black rail is a mouse-sized member of the rail family Rallidae that occurs in both North and South America.
The Pacific reef heron, also known as the eastern reef heron or eastern reef egret, is a species of heron found throughout southern Asia and Oceania. It occurs in two colour morphs with either slaty grey or pure white plumage. The sexes are similar in appearance.
Nycticorax is a genus of night herons. The name Nycticorax means "night raven" and derives from the Ancient Greek νύκτος, nuktos "night" and κοραξ, korax, "raven". It refers to the largely nocturnal feeding habits of this group of birds, and the croaking crow-like call of the best known species, the black-crowned night heron.
The nankeen night heron is a heron that belongs to the genus Nycticorax and the family Ardeidae. Due to its distinctive reddish-brown colour, it is also commonly referred to as the rufous night heron. It is primarily nocturnal and is observed in a broad range of habitats, including forests, meadows, shores, reefs, marshes, grasslands, and swamps. The species is 55 to 65 cm in length, with rich cinnamon upperparts and white underparts. The nankeen night heron has a stable population size, and is classified as a species of least concern by the International Union for Conservation of Nature (IUCN).
The Rodrigues night heron is an extinct species of heron that was endemic to the Mascarene island of Rodrigues in the Indian Ocean. The species was first mentioned as "bitterns" in two accounts from 1691–1693 and 1725–1726, and these were correlated with subfossil remains found and described in the latter part of the 19th century. The bones showed that the bird was a heron, first named Ardea megacephala in 1873, but moved to the night heron genus Nycticorax in 1879 after more remains were described. The specific name megacephala is Greek for "great-headed". Two related extinct species from the other Mascarene islands have also been identified from accounts and remains: the Mauritius night heron and the Réunion night heron.
The Malayan night heron, also known as Malaysian night heron and tiger bittern, is a medium-sized heron. It is distributed in southern and eastern Asia.
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.