Whistling heron | |
---|---|
Adult S. s. sibilatrix The Pantanal, Brazil | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Ardeidae |
Subfamily: | Ardeinae |
Genus: | Syrigma Ridgway, 1878 |
Species: | S. sibilatrix |
Binomial name | |
Syrigma sibilatrix (Temminck, 1824) | |
Synonyms | |
|
The whistling heron (Syrigma sibilatrix) is a medium-sized, often terrestrial heron of South America. It is the only species placed in the genus Syrigma. There are two subspecies, the southern S. s. sibilatrix and the northern S. s. fostersmithi.
A molecular phylogenetic study published in 2023 found that within the heron family the whistling heron is most closely related to the capped heron (Pilherodius pileatus). [2]
Two subspecies are recognised: [3]
The whistling heron measures 53 to 64 cm in length and weighs 521 to 546 g. The southern subspecies is bigger but has a shorter bill in proportion to the body. [4]
The overall impression of standing birds is gray, with flying birds showing conspicuous white rear parts (lower back, belly, and tail). In both subspecies, adults' upperparts except the lower back are blue-gray. [4] [5] The feathers of the sides of head, sides of the neck, breast, and scapular area are basically white but are stained gold to buff, perhaps by the powder down typical of herons or by secretions of the preen gland; the color varies from bird to bird. In the nominate subspecies, the crown and crest (separate plumes up to 4 cm long on the nape) are black and the upper wing coverts are cinnamon-colored; the crown and crest are slate-gray and the upper wing coverts are honey-colored (or "chamois" [5] ) in fostersmithi. [4] The bill is pink with blue to violet at the base and the distal third black, the legs are greenish and rather short, and there is a fairly big area of bare bluish skin around the eye. [4] [5]
Juveniles have the same overall pattern but are duller than adults, with the crown lighter, the breast light gray, and the throat and sides unstained white. [4] [5] Chicks are undescribed. [4]
The bird is named for its most common call, a "loud, flute-like whistled kleeer-er" [5] or "a high, reedy, complaining whistle, often doubled or uttered in a ser[ies], wueeee, wueeee,.…, easily imitated" [6] or "a distinctive, characteristic, far-carrying, melodious whistle" that "can be rendered 'kee, kee, kee.'" [4] It may also give "a slow, drawn-out whistle" when taking off. [4] The alarm call is a harsh quah-h-h. [5]
Unlike other herons, in flight it has fast, duck-like wingbeats and usually does not retract its neck fully. [4]
The subspecies fostersmithi inhabits the Llanos and the Orinoco basin of Colombia and Venezuela. [4] [5] The subspecies sibilatrix inhabits eastern Bolivia, Paraguay, western and southern Brazil, Uruguay, Chile, and northeastern Argentina. Recent records suggest that it may be expanding its range northward and eastward in Brazil. It makes seasonal movements at least in northeastern Venezuela, where it does not occur from November to January, but remains all year in other areas, such as Buenos Aires Province, Argentina. [4]
It occurs at elevations up to 500 m (with a sight record from 2300 m [6] ) in seasonally flooded savanna, often in drier grassy situations than other herons, but also in a wide variety of open waterlogged or shallowly submerged terrain. Because it roosts in trees, it particularly likes regions where open areas are mixed with woodlots. It has no objection to human-altered habitats such as pastures and roadsides, and it often perches on fenceposts. [4]
Although patchily distributed, it is common in many areas, with no population considered vulnerable. It benefits from deforestation and some agriculture. [4] As a successful heron of dry tropical country, it has been compared to two species originating in the Old World: the cattle egret and the black-headed heron. [7]
This species eats any small dryland and marsh animals it can catch, or even pirate [4] (as from an aplomado falcon in one reported incident [7] ). It often holds still [4] [5] [6] but also walks very slowly [7] and may use more active techniques, even running after prey or catching flying insects (notably dragonflies [6] ) from a standing position. [4] It may allow humans to approach fairly closely rather than leave a good feeding spot. [4] It typically feeds alone or in pairs, but is sometimes seen in groups up to 100, [5] especially before roosting for the night. [4]
In a courtship display, the birds fly back and forth and glide in circles. A captive pair displayed by raising their plumes. [4]
This species nests alone, unlike most herons, which nest in colonies. It may nest in mature trees such as araucarias or exotic trees. [4] One nest in Argentina was loosely built of sticks about 4m up in a eucalyptus. [6] The eggs are pale blue and speckled, about 4.7 × 3.6 cm, and the normal clutch is three or four. Incubation lasts about 28 days, and young fledge 42 days after hatching. Egg survival has been measured at 28% and nestling survival at 40%; storms that destroy nests are an important cause of losses. Based on observations of family groups, only two young normally fledge. Unlike most heron species, whistling herons care for young after leaving the nest; juveniles beg for food by hissing with their wings drooped. [4]
Indigenous peoples formerly used its neck plumes as trade items, though not so heavily as to reduce populations. [4]
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 this represents a white color morph of the great blue heron, a subspecies of it, or an entirely separate species.
The boat-billed heron, colloquially known as the boatbill, is an atypical member of the heron family. It is the only member of the genus Cochlearius and was formerly placed in a monotypic family, the Cochleariidae. It lives in mangrove swamps from Mexico south to Peru and Brazil. It is a nocturnal bird, and breeds semicolonially in mangrove trees, laying two to four bluish-white eggs in a twig nest.
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 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 jabiru is a large stork found in the Americas from Mexico to Argentina, except west of the Andes. It sometimes wanders into the United States, usually in Texas, but has also been reported in Mississippi, Oklahoma and Louisiana. It is most common in the Pantanal region of Brazil and the Eastern Chaco region of Paraguay. It is the only member of the genus Jabiru. The name comes from the Tupi–Guaraní language and means "swollen neck".
The fulvous whistling duck or fulvous tree duck is a species of whistling duck that breeds across the world's tropical regions in much of Mexico and South America, the West Indies, the southern United States, sub-Saharan Africa and the Indian subcontinent. It has plumage that is mainly reddish brown, long legs and a long grey bill, and shows a distinctive white band across its black tail in flight. Like other members of its ancient lineage, it has a whistling call which is given in flight or on the ground. Its preferred habitat consists of wetlands with plentiful vegetation, including shallow lakes and paddy fields. The nest, built from plant material and unlined, is placed among dense vegetation or in a tree hole. The typical clutch is around ten whitish eggs. The breeding adults, which pair for life, take turns to incubate, and the eggs hatch in 24–29 days. The downy grey ducklings leave the nest within a day or so of hatching, but the parents continue to protect them until they fledge around nine weeks later.
The agami heron is a medium-sized heron. It is a resident breeding bird from Central America south to Peru and Brazil. It is sometimes known as the chestnut-bellied heron, and is the only member of the genus Agamia. In Brazil it is sometimes called Soco beija-flor, meaning 'hummingbird heron', thanks to its unique coloration pattern.
The bat falcon is a bird of prey in the family Falconidae, the falcons and caracaras. It is found in Mexico, Central America, Trinidad, and every mainland South American country except Chile and Uruguay.
The grey-fronted dove is a large New World tropical dove. It is found on Trinidad and in every mainland South American country except Chile.
The short-tailed swift is a bird in the Apodidae, or swift family.
The black heron, also known as the black egret, is an African heron. It is well known for its habit of using its wings to form a canopy when fishing.
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 violet-tailed sylph is a species of hummingbird in the "coquettes", tribe Lesbiini of subfamily Lesbiinae. It is found in Colombia and Ecuador.
The white-tailed goldenthroat is a species of hummingbird in the subfamily Polytminae, the mangoes. It is found in Argentina, Bolivia, Brazil, Colombia, French Guiana, Guyana, Paraguay, Peru, Suriname, Trinidad and Tobago, and Venezuela.
The cocoi heron is a species of long-legged wading bird in the heron family Ardeidae found across South America. It has predominantly pale grey plumage with a darker grey crest. A carnivore, it hunts fish and crustaceans in shallow water.
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 fasciated tiger heron is a species of heron in the family Ardeidae. It is present in southern Central America and parts of northern and central South America, where its natural habitat is rivers.
The rufescent tiger heron is a species of heron in the family Ardeidae. It is found in wetlands from Central America through much of South America.
The violaceous quail-dove is a species of bird in the family Columbidae. It is found in Argentina, Bolivia, Brazil, Colombia, Costa Rica, Guyana, Nicaragua, Panama, Paraguay, Peru, Suriname, and Venezuela.
The white-naped xenopsaris, also known as the reed becard and white-naped becard, is a species of suboscine bird in the family Tityridae, the only member of the genus Xenopsaris. It is found in South America, in humid subtropical and tropical savanna climates in most of the countries east of the Andes: Venezuela, Brazil, Bolivia, Paraguay, Uruguay, and Argentina. Living in open woodland and other open forest habitats, it is mostly sedentary, though some populations may be migratory. The species, which is closely related to becards and tityras, was thought to be either a tyrant-flycatcher or cotinga, before it was placed in Tityridae.