Black-necked Stork (Ephippiorhynchus asiaticus)

Black-necked Stork

[order] CICONIIFORMES | [family] Ciconiidae | [latin] Ephippiorhynchus asiaticus | [authority] Latham, 1790 | [UK] Black-necked Stork | [FR] Jabiru d’Asie | [DE] Riesenstorch | [ES] Jabiru Asiatico | [NL] Zwarthalsooievaar

Subspecies

Monotypic species

Genus

Tribe Leptoptilini comprising ?giant storks? basically constitutes two forms, genus Ephippiorhynchus and Jabiru in one group and genus Leptoptilos in the other. Ephippiorhynchus is a small genus of storks. It contains two living species only, very large birds more than 140 cm tall with a 230?270 cm wingspan. Both are mainly black and white, with huge colourful, mainly red and black bills. The sexes of these species are similarly plumaged, but differ in eye colour. The members of this genus are sometimes called “jabirus”, but this properly refers to a close relative from Latin America. A prehistoric relative, Ephippiorhynchus pakistanensis, has been described from Late Miocene fossils found in Pakistan. At about the same time, another now-extinct species occurred in eastern to central Africa. These large wading birds breed in marshes and other wetlands, building a large, deep stick nest in a tree. Like most storks, they fly with the neck outstretched, not retracted like a heron; in flight, they present a strange shape, with the head and large bill somewhat drooping down. They are silent except for bill-clattering at the nest. Ephippiorhynchus storks, like most of their relatives, feeds mainly on fish, frogs and crabs, but also on young birds, and other land vertebrates. They move in a deliberate and stately manner as they hunt, in a similar way to the larger heron. These birds are not infrequently kept in captivity by zoos or aviculturalists. Individuals occasionally escape, and these have been proposed to be responsible for sightings of “Big Bird” cryptids; the Saddle-billed Stork is the most likely basis for the Kongamato. The genus name Ephippiorhynchus is derived from Ancient Greek ephippos, a saddle (literally “something which is placed on a horse”), and rhynchus, “bill”, and refers to the frontal shield which saddles the bill of one species.

Physical charateristics

A very large and characteristic stork. Adults have bright red legs, white body, extensive black in the wings and tail and notably a glossy iridescent black head and neck with big black bill. Genus Ephippiorhynchus unique among storks in showing sexual dimorphism in colouration: iris dark brown in male and yellow in female. Immature mostly dull brown. Similar spp. Unmistakeable. No similar spp. within the range.


wingspan min.: 0 cm wingspan max.: 0 cm
size min.: 129 cm size max.: 150 cm
incubation min.: 28 days incubation max.: 32 days
fledging min.: 90 days fledging max.: 110 days
broods: 1   eggs min.: 2  
      eggs max.: 4  

Range

Oriental Region, Australasia : India to Australia

Habitat

It inhabits freshwater marshes and lakes3,16, pools in open forest and large rivers and flooded grassland3, up to an altitude of 1200 m. It occasionally uses mangroves and coastal habitats, such as estuaries and brackish lagoons. It also frequents artificial habitats such as reservoirs, sewage ponds and irrigation stores. Although it shows a preference for natural wetlands throughout the year, it uses similar artificial habitats like rice paddies for a short period of time, particularly during and after the monsoon season, when natural wetlands may become too deep for foraging. It will also forage in wet or dry wheat fields and flooded fallow fields, the latter especially in summer when the extent of natural wetlands is reduced.

Reproduction

It is a territorial breeder, and pairs stay together during successive seasons, some even after breeding is over. Nests are built in old trees. In India, it starts to nest from August onwards, with earlier breeders in northern India timing their egg laying in September and October to coincide with the end of the monsoon season. In New South Wales, Australia, eggs are laid from May to August, with fledging occurring between October and January. Breeding pairs generally raise one or two chicks and three is not uncommon, although four is rare. Chicks generally stay in natal territories until the subsequent breeding season, although they stay longer if adult birds do not breed in the subsequent year.

Feeding habits

It is carnivorous and has high food requirements, tending to be largely territorial, being recorded in flocks very occasionally, and becoming more aggressive as food is depleted. It feeds in shallow water up to 0.5m deep, and takes fish, reptiles and frogs, some waterfowl and turtle eggs. It has been observed using tactile feeding methods most often, although visual methods are also used, depending on the habitat and prey-type.

Video Black-necked Stork

httpv://www.youtube.com/watch?v=EAiY4uf5wYU

copyright: Eldert Groenewoud


Conservation

Overall, this species has undergone a moderately rapid population reduction, which is projected to continue, and it has a moderately small population. It is therefore classed as Near Threatened.
Ephippiorhynchus asiaticus occurs in South Asia, South-East Asia and Oceania. In South Asia it is found in Pakistan (previously frequent in lower Sind, breeding in the Indus delta until the 1970s, now a straggler), Nepal (rare resident and winter visitor to the terai), India (a widespread resident, but now generally rare and local, and may now be absent in many areas in the south), Bhutan (likely as a non-breeder), Bangladesh (former resident, now a vagrant), and Sri Lanka (fewer than 50 mature individuals resident, principally in the dry lowlands). In South-East Asia it occurs in Myanmar (formerly a widespread resident, current status unclear but certainly scarce), Thailand (formerly quite widespread, now a rare resident in the peninsula, almost extinct), Laos (previously a widespread non-breeding visitor, probably breeding in the south, but now extremely rare), Cambodia (previously fairly common; regular recent records, with small numbers breeding), and Indonesia (apparently once present in the Sundaic region, but now extinct there; population >650 in south Papua, formerly Irian Jaya). The species was thought to be extinct in Vietnam, with no records since 1987, but in 2003, two individuals were recorded during a survey of Yok Don National Park. In Oceania it is found in Papua New Guinea (very local, but occasionally not uncommon) and Australia (relatively large population in the north). The combined South and South-East Asia populations are thought to number fewer than 1,000 individuals. While it is in decline in South Asia, in South-East Asia it has dwindled to the brink of extinction. However, a population of c.29 pairs studied in Uttar Pradesh (India) had high productivity and low mortality and has been judged to be at least stable, if not a source for neighbouring populations2. The districts of south-western Uttar Pradesh are the species’s stronghold in India. Between 1996 and 2003, the species was judged to be in decline at 32 (54%) of the 59 sites in India where it was recorded6. It is probably stable in south Papua and Australia, although confirmation of the trend in south Papua is required. A recent estimate places the Australian population at up to 20000 breeding individuals and secure, although it has been contested that this is unduly optimistic and that the figure may not exceed 10000. These estimates have been used to extrapolate a global total of c.31,000 individuals6. However, owing to the uncertainty surrounding this estimate, a range of 10000-21000 mature individuals is preferred as a conservative estimate of the total breeding population.
Black-necked Stork status Near Threatened

Migration

Mostly sedentary but
they are fairly nomadic, but have also been known to settle down in areas where ample food and water are available such as Kakadu

Distribution map

Black-necked Stork distribution range map

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