(2238) Ixobrychus cinnamomeus.
The Chestnut Bittern. *
Ardea cinnamomea Gmelin, Syst. Nat., i, p. 643 (1789) (China). Ardetta cinnamomea. Blanf. & Oates, iv, p. 402.
Vernacular names. Lal-bogla (Hind.); Khyri-Bogla (Beng.); Kuruttu-koku (Tam., Ceylon); Metti-korowaka (Cing.).
Description. - Male. Whole upper plumage chestnut-cinnamon, the wing-coverts slightly paler; in fresh plumage some birds have a wash of grey on the head and the outer secondaries are distinctly tipped with grey; chin, throat and upper fore-neck white with a central streak of blackish or deep rufous ; lower fore-neck and extreme upper breast chestnut, paler than the back; a patch of black, buff-edged feathers on each side of the breast nearly concealed by the long chestnut feathers of the upper breast; flanks, abdomen and under tail-coverts pale chestnut; axillaries and under wing-coverts still paler and with a pink tinge.
Colours of soft parts. Iris yellow, orange or pinky red; bill yellow, the culmen darker and browner; naked skin deep red or reddish-purple in males, yellowish in females; legs and feet yellowish-green, the soles paler and more yellow.
Measurements. Wing 138 to 149 mm. (once 156 mm.); tail 41 to 45 mm.; tarsus 45 to 50 mm.; culmen 43 to 51 mm.
Female. Above chestnut-brown, the crown blackish; scapulars and wing-coverts with buff, black-bordered spots, obsolete in old birds; the first few primaries are mottled with brownish at the base of the inner webs; sides of head rufous or rufous-brown ; underparts buffy-rufous, streaked with dark brown from chin to vent; under wing-coverts and axillaries darker rufous-buff.
Young birds are like the female but more definitely barred and spotted above ; less chestnut and more brown; the lower plumage still more heavily streaked with dark brown.
Distribution. India, Ceylon, Burma, China to the Amur, Malay States and Archipelago to the Philippines and Celebes. In India it breeds in Travancore and on the Malabar coast, though it is not common; in "Western India from Cutch, Rajputana and Sind to the North-West Provinces it is a breeding visitor when the Rains start. In E. Bengal and Assam Eastwards it is a very common resident throughout the year.
Nidification, The Chestnut Bittern breeds during the Rains, i. e., from about the 15th of June to the end of September, making a typical nest among reeds in swamps or at the edge of lakes and quite small ponds. The normal clutch of eggs is four or five and in colour they are pure white when just laid but soon become stained and yellowish. Fifty eggs average 35.5 x 26.4 mm. t maxima 39.8 x 25.5 and 37.0 x 28.0 mm.; minima 33.1 x 26.0 and 37.1 X 25.0 mm.
Habits those of the genus, though this is much the most common species in India and Burma. In Sind and the North-West it appears to leave as soon as the country dries up and is never so common as it is in Assam and Burma, where it is very numerous in many of the big swamps. It is Crepuscular in its habits but when it is undisturbed often feeds during the day if deep shade is available. It is as shy as most Bitterns are and as loth to fly if it can creep or climb away through the reeds.