The painted stork (Mycteria leucocephala) is a large wader in the stork family. It is found in the wetlands of the plains of tropical Asia south of the Himalayas in the Indian Subcontinent and extending into Southeast Asia. Their distinctive pink tertial feathers of the adults give them their name. They forage in flocks in shallow waters along rivers or lakes. They immerse their half open beaks in water and sweep them from side to side and snap up their prey of small fish that are sensed by touch. As they wade along they also stir the water with their feet to flush hiding fish. They nest colonially in trees, often along with other waterbirds. The only sounds they produce are weak moans or bill clattering at the nest. They are not migratory and only make short-distance movements in some parts of their range in response to changes in weather or food availability or for breeding. Like other storks, they are often seen soaring on thermals.
This large stork has a heavy yellow beak with a down-curved tip that gives it a resemblance to an ibis. The head of the adult is bare and orange or reddish in colour. The long tertials are tipped in bright pink and at rest they extend over the back and rump. There is a distinctive black breast band with white scaly markings. The band continues into the under-wing coverts and the white tips of the black coverts give it the appearance of white stripes running across the under-wing lining.
The rest of the body is whitish in adults and the primaries and secondaries are black with a greenish gloss. The legs are yellowish to red but often appear white due their habit of urohidrosis or defecating on their legs especially when at rest. The short tail is black with a green gloss.[2] For a stork, it is medium-sized, standing about 93–102 cm (36.5–40 in) tall, 150–160 cm (59–63 in) in wingspan and weighing 2–3.5 kg (4.4–7.7 lb). Males and females appear alike but the males of a pair are usually larger than the female.
The downy young are mainly whitish with grey bills and blackish facial skin. The juveniles assume a brownish plumage and like most other storks reach breeding condition after two to three years.
Like all storks, they fly with their neck outstretched. They often make use of the late morning thermals to soar in search of foraging areas. Like other storks they are mostly silent but clatter their bills at nest and may make some harsh croaking or low moaning sounds at nest.
In the past the species has been placed in the genera Ibis, Tantalus and Pseudotantalus. The slight curve to the beak led them to be considered as a relative of the ibises. The older genus names were based on Greek mythology where Tantalus was punished by having to stand in a pool of water. T C Jerdon called it the "Pelican Ibis". Later studies placed along with the wood-storks in the genus Mycteria, members of which have similar bill structure and share a common feeding behaviour of sweeping their half-open bill from side to side inside water as they wade[8] and their evolutionary affinity has been confirmed by sequence based studies.
The painted stork is widely distributed over the plains of Asia. They are found south of the Himalayan ranges and are bounded on the west by the Indus River system where they are rare and extend eastwards into Southeast Asia. They are absent from very dry or desert regions, dense forests and the higher hill regions. They are rare in most of Kerala and the species appears to have expanded into that region only in the 1990s. They prefer freshwater wetlands in all seasons, but also use irrigation canals and crop fields, particularly flooded rice fields during the monsoon. They are resident in most regions but make seasonal movements. Young birds may disperse far from their breeding sites as demonstrated by a juvenile ringed at a nest in Keoladeo National Park that was recovered 800 kilometres away at Chilka in eastern India. Breeding is always on large trees, usually in areas where nesting trees are secured over long periods of time, including in wetland reserves, along community-managed village ponds and lakes, inside villages when protection is also afforded to nesting birds like in Kokrebellur, protected tree patches in urban locations such as zoos, and on islands in urban wetlands.
Painted storks feed in groups in shallow wetlands, crop fields and irrigation canals. The maximum success of finding prey was at 7 cm of water depth at Keoladeo-Ghana National Park. They feed mainly on small fish which they sense by touch while slowly sweeping their half open bill from side to side while it held submerged. They walk slowly and also disturb the water with their feet to flush fish. They also take frogs and the occasional snake. They forage mainly in the day but may forage late or even at night under exceptional conditions. After they are fed they may stand still on the shore for long durations. Flock sizes in agricultural landscapes are mostly small (<5 birds) but reach flocks of over 50 birds. In such landscapes, flock sizes do not vary much between seasons, but densities are much higher in winter after chicks of the year have fledged from nests.
Painted storks breed on trees either in mixed colonies along with other water birds, or by themselves. The breeding season begins in the winter months shortly after the monsoons. In northern India, the breeding season begins in mid-August while in southern India the nest initiation begins around October and continues till February and or even until April. One detailed study in Bengaluru city saw storks building nests between early February and mid-March, with all of the observed nests having fledgelings by mid-May. Considerable variation is noticed in the onset of breeding across sites with the season at Kokrebellur and Edurupattu around January or February but at Telineelapuram, Kundakulam and Tirunelveli the breeding begins around October or November.
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