Straw-necked ibis | |
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Adult in Queensland | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Pelecaniformes |
Family: | Threskiornithidae |
Genus: | Threskiornis |
Species: | T. spinicollis |
Binomial name | |
Threskiornis spinicollis (Jameson, 1835) | |
The straw-necked ibis (Threskiornis spinicollis) is a bird of the ibis and spoonbill family Threskiornithidae. It can be found throughout Australia, New Guinea, and parts of Indonesia. Adults have distinctive straw-like feathers on their necks.
Straw-necked ibises are large birds, around 59–76 cm (23–30 in) long, with a bare black head and a long, downcurved black bill. They have a distinctive, highly iridescent plumage, which can appear fairly uniform dirty dark brown in indifferent light; [2] the wings are dark, with an iridescent, multicoloured sheen in sunlight. They have a shiny blue-black back, with a metallic purple, green and bronze glow, and a dark collar. [2] The upper neck is white, as are the underparts and the undertail; their legs are usually red near the top and dark grey toward the feet. Adults have straw-colored feathers on the neck, giving the bird its common name. [3] [4] Their wingspan is about 100–120 cm (39.5–47 in) and weight is generally 1.1–1.5 kg (2.5–3.5 lb). [2]
Sexes are similar, although males have longer bills and females have a dark band across their upper breast. Juveniles have duller colors and shorter bills with less curvature, and lack the straw-like plumes on the neck. [5]
Straw-necked ibises are commonly found throughout Australia, nesting at least occasionally in all mainland states and territories, except in the arid interior. [6] They are most abundant on the east coast, and are vagrant to New Zealand, Norfolk Island and Lord Howe Island. [7] They are less frequently seen in New Guinea, Indonesia, and occasionally in Tasmania and other islands of the Bass Strait. [8] [2]
Found around shallow freshwater wetlands, cultivated pastures, edges of swamps and lagoons, and wet or dry grasslands. They tend to avoid arid and saltwater areas, and coastal mudflats. They are extremely nomadic, and are constantly on the move searching for suitable habitats. [9] They are frequently seen standing on high branches of bare trees, silhouetted against the sky. [10]
Straw-neck ibises are partly migratory: some birds are sedentary, while others make seasonal or erratic movements when water conditions vary. Seasonal migrations are recorded from south-eastern and northern Australia, as well as from coast and inland wetlands in central Australia, and across the Torres Strait between north-eastern Australia and southern New Guinea. Non-breeding migrants arrive in western Australia and leave in autumn, the arrival dates are closely correlated with rainfall during the preceding spring. They typically fly in line or in V formation, reaching high altitudes during long-distance movements. [2]
Vocalizations are made mainly around breeding colonies; calls are composed of croaks, barks and grunts. In flight, at intervals, they may produce a hoarse grunt. They feed in flocks of up to 200 birds; they probe in soil, mud, crevices, vegetation or shallow water. [2]
Straw-necked ibises feed primarily on aquatic and terrestrial invertebrates, although their diets can vary. [6] In shallow waters, straw-necked ibises feed on aquatic insects, molluscs, frogs, freshwater crayfish ( Cherax ) and fish. On land, they thrive on insects such as grasshoppers, crickets, and locusts, and are often called the Farmer's Friend because they eat pests that would otherwise eat farm crops. They also eat skinks and other small lizards, and small reptiles, as well as rodents. [8] [9]
Compared to the Australian white ibis, they have not adapted to a wide variety of food and are only rarely opportunistic scavengers of human waste. [8] Citizen scientists have reported seeing them eat cane toads ( Bufo marinus ), avoiding being poisoned by flicking the toads about until they release the toxin which is their defence mechanism, then taking them to a creek to wash them [2] [11]
Breeding season is highly variable, mainly influenced by water conditions. In southwestern Australia, it normally occurs from August to December; occasional breeding takes place in the north, but on a very small scale. [6] [12] Breeding has been observed for all months throughout the central and northern regions, usually occurring over the year following heavy rain in some areas. [2]
They build a large, rough, cup-shaped nest of sticks and trampled plants among reeds, paperbarks, bulrushes, or trees over water. They breed in colonies, often with the Australian white ibis. Nests are used year after year. [8] Clutches vary from 2–5 eggs, with an incubation period of around 24 to 25 days, by both parents. Both parents feed and care for the young, about 35 days after hatching. Feeding is by regurgitation and continues up to two weeks after leaving the nest. [6]
The family Threskiornithidae includes 36 species of large wading birds. The family has been traditionally classified into two subfamilies, the ibises and the spoonbills; however recent genetic studies have cast doubt on this arrangement, and have found the spoonbills to be nested within the Old World ibises, and the New World ibises as an early offshoot.
The glossy ibis is a water bird in the order Pelecaniformes and the ibis and spoonbill family Threskiornithidae. The scientific name derives from Ancient Greek plegados and Latin, falcis, both meaning "sickle" and referring to the distinctive shape of the bill.
The Australian white ibis is a wading bird of the ibis family, Threskiornithidae. It is widespread across much of Australia. It has a predominantly white plumage with a bare, black head, long downcurved bill and black legs. While it is closely related to the African sacred ibis, the Australian white ibis is a native Australian bird – contrary to urban myth, it is not a feral species introduced to Australia by people, and it does not come from Egypt.
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 long-toed stint is a small wader. The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds. The specific subminuta is from Latin sub, "near to" and minuta, "small" from its similarity to the little stint, Calidris minuta.
The African spoonbill is a long-legged wading bird of the ibis and spoonbill family Threskiornithidae. The species is widespread across Africa and Madagascar, including Botswana, Kenya, Mozambique, Namibia, South Africa, and Zimbabwe.
The black-necked stork is a tall long-necked wading bird in the stork family. It is a resident species across the Indian Subcontinent and Southeast Asia with a disjunct population in Australia. It lives in wetland habitats and near fields of certain crops such as rice and wheat where it forages for a wide range of animal prey. Adult birds of both sexes have a heavy bill and are patterned in white and irridescent blacks, but the sexes differ in the colour of the iris with females sporting yellow irises and males having dark-coloured irises. In Australia, it is sometimes called a jabiru although that name refers to a stork species found in the Americas. It is one of the few storks that are strongly territorial when feeding and breeding.
The black-headed ibis, also known as the Oriental white ibis, Indian white ibis, and black-necked ibis or colloquially as 'bin chicken', is a species of wading bird of the ibis family Threskiornithidae which breeds in the South and Southeast Asia from India to the west and as far east as Japan. It is the only native ibis species in its range that has an overall white plumage with a black neck and head. The down-curved beak and legs are also black. Though often referred to as a wetland species, the black-headed ibis forages in a range of natural and man-made habitats. This species of ibis nests only during the rainy season.
The giant ibis is a wading bird of the ibis family, Threskiornithidae. It is confined to northern Cambodia, with a few birds surviving in extreme southern Laos and a recent sighting in Yok Đôn National Park, Vietnam. It is sometimes placed in the genus Thaumatibis.
The African sacred ibis is a species of ibis, a wading bird of the family Threskiornithidae. It is native to much of Africa, as well as small parts of Iraq, Iran and Kuwait. It is especially known for its role in Ancient Egyptian religion, where it was linked to the god Thoth. The species is currently extirpated from Egypt.
The yellow-billed spoonbill is a gregarious wading bird of the ibis and spoonbill family, Threskiornithidae. It is native to Australia, and is a vagrant to New Zealand, Lord Howe Island and Norfolk Island.
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 red-naped ibis also known as the Indian black ibis or black ibis is a species of ibis found in the plains of the Indian Subcontinent. Unlike other ibises in the region it is not very dependent on water and is often found in dry fields a good distance away from water. It is usually seen in loose groups and can be told by the nearly all dark body with a white patch on the shoulder and a bare dark head with a patch of crimson red warty skin on the crown and nape. It has a loud call and is noisy when breeding. It builds its nest most often on the top of a large tree or palm.
Threskiornis is a genus of ibises, wading birds of the family Threskiornithidae. They occur in the warmer parts of the Old World in southern Asia, Australasia and Sub-Saharan Africa. They are colonial breeders, which build a stick nest in a tree or bush and lay two to four eggs. They occur in marshy wetlands and feed on various fish, frogs, crustaceans and insects. In English, they are called sacred ibises. In Australia, urban dwelling ibises are known colloquially as "bin chickens".
Eudocimus is a genus of ibises, wading birds of the family Threskiornithidae. They occur in the warmer parts of the New World with representatives from the southern United States south through Central America, the West Indies, and South America.
The hadeda ibis is an ibis native to Sub-Saharan Africa. It is named for its loud three to four note calls uttered in flight especially in the mornings and evenings when they fly out or return to their roost trees. Although not as dependent on water as some ibises, they are found near wetlands and often live in close proximity to humans, foraging in cultivated land and gardens. A medium-sized ibis with stout legs and a typical down-curved bill, the wing coverts are iridescent with a green or purple sheen. They are non-migratory but are known to make nomadic movements in response to rain particularly during droughts. Their ranges in southern Africa have increased with an increase in tree cover and irrigation in human-altered habitats.
The white-necked heron or Pacific heron is a species of heron that is found on most of the Australian continent wherever freshwater habitats exist. It is also found in parts of Indonesia, New Guinea and New Zealand, but is uncommon in Tasmania. The populations of this species in Australia are known to be nomadic like most water birds in Australia, moving from one water source to another often entering habitats they have not previously occupied, taking advantage of flooding and heavy rain where the surplus of food allows them to breed and raise their young. Population explosions have been known when the environmental conditions are right for this species in places where they have been rare or unknown.
The spot-breasted ibis is a small, forest-dwelling ibis found in African lowland forests and swampy forested areas. Its preference for dense rainforests in tropical Africa means that it is seldom seen and is vulnerable to deforestation.
The plumbeous ibis, also formerly called the blue ibis, is a large distinctive ibis species endemic to parts of central South America.
The Malagasy sacred ibis is a relatively large, heavily built ibis endemic to the west coast of Madagascar, and Aldabra on the Seychelles.