(2215) Anastomus oscitans.
Ardea oscitans Bodd., Tabl Pl.. Enlum., p. 55 (1783) (Pondicherry). Anastomus oscitans. Blanf. & Oates, iv, p. 277.
Vernacular names. Gunqla, Ghongal, Ghonghila (Hind.); Dokar (Behar) ; Tonte-bhanga, Shamaeh-banya, Samuk-khol, Hammak-kas (Bi-sng.); Poima konya (Southern G-onds); Galu-konga (Tel.); Nati-kuti nareh (Tam.): Karunary (Tam., Ceylon); Gombelle-koka (Cing.); Samuk-bhanga (Assam) ; Karu-tsoke (Burma).
Description. - Breeding plumage. Longest scapulars, primaries and secondaries, bastard wing, primary and secondary coverts and tail black, glossed with purple and dark green ; remainder of plumage white.
Colours of soft parts. Iris almost white, grey or pale brown; bill dull greenish-horny, redder beneath ; orbital skin and naked lores black; legs and feet dull fleshy.
Measurements. Wing 392 to 408 mm.; tail 183 to 217 mm. ; tarsus about 140 to 150 mm.; culmen 153 to 162 mm.
In non-breeding plumage the white of the upper parts is replaced with pale smoky-grey.
Young birds have the head, neck and upper breast darker, smoky brown-grey, the feathers of the breast dark-shafted; the mantle is blackish-brown the feathers with pale rufous-grey edges ; wing-coverts with dark shafts.
Distribution. The whole of India, Ceylon, Assam. Burma. Siam and Cochin China.
Nidification. The Open-bills seem everywhere to breed principally in July and August, except in Ceylon, where they lay during January, February and March, and in Southern Madras, where Packard took eggs early in December. They associate in colonies of some size, occasionally as large as 400 to 500 pairs, generally keeping aloof from other birds. Sometimes they breed with the Painted Stork and various Herons, but even then seldom build in the same trees with them. The nests are big affairs of sticks, often used for several years, when they become very large, and are placed on trees standing close to, or actually in, the water. One of the large colonies above referred to was in an Assamese village and nine out of ten of the nests were in palm-trees, The destruction during storms was very great but the birds continued to breed, making fresh nests and laying again. The eggs, three to five in number, are broad ovals but little com pressed towards the smaller end, Eighty eggs average 57.8 x 41.1 mm: maxima 64.0 X 40.6 and 52.4 x 43.4 mm.; minima 48.3 x 38.2 and 56.1 x 36.4 mm.
Habits. The Open-bill is perhaps the most common and widely distributed of all our Storks and there are few well-watered districts where it may not be found during the Rains, though it leaves many of the drier during the drought at the end of the Cold Weather. It feeds principally on mollusca, chiefly Ampularia, crushing the shell and then extracting the contents. Land-snails, crabs and the small mollusca it crushes first and then swallows, shell and all. It also eats worms, frogs, lizards, small snakes, insects and fish. The flight is very strong and the birds often spend hours flying high in the air, soaring over their breeding-grounds. They dance like all the Storks and make the same curious clapping noise with their bills whilst they also have a low grunt, which one can only hear when standing very close to them.