(933) Prinia flaviventris flaviventris.
The Yellow-bellied Wren-Warbler.
Orthotomus flaviventris Deless , Rev. Zool., 1840, p. L01 (Bhutan) Prinia flaviventris. Blanf. & Gates, i, p. 449.
Vernacular names. Daotisha gurrmu (Cachari).
Description. Forehead and crown dark ashy, shading into ashy-green on the nape and olive-green on the upper plumage and closed wings ; tail olive-green, obsoletely cross-rayed, tipped paler and sometimes faintly subtipped darker; lores dusky brown; a white eyebrow, not always present; a ring round the eye yellowish white; chin, throat and breast white, suffused with fulvous in varying degree; sides of the head and throat ashy ; remainder of lower plumage bright yellow.
Colours of soft parts. Iris tan-brown; bill black in Summer, homy-brown in Winter, paler below; legs and feet fleshy-orange
Measurements. Wing 42 to 49 mm.; tail 56 to 70 mm. -tarsus about 21 mm.; culmen about 10 to 11 mm.; Southern Burmese birds have larger bills measuring 11 to 12 mm.
In Winter the tail is longer, but the white eyebrow said by Oates to be a Winter character appears to be an individual one, some birds having it in both Summer and Winter whilst other birds have no signs of it.
Distribution. The Nepal Terai, Himalayas to East and South Assam; Eastern Bengal, Burma and Malay States to Singapore and West Sumatra.
Nidification. The Yellow-bellied Wren-Warbler breeds overall its range after the rains break from the end of June to September; in Assam, however, where there is more rain earlier in the year, they commence breeding m early May. They breed at all elevations up to 3,000 feet and even up to 3,500 feet on rare occasions, but generally below 2,500 feet. The nest is made of shreds of grass-blades and is egg-shaped with a comparatively large entrance near the top ; there is no lining as a rule, though sometimes finer grass-stems are used for this purpose. It is placed in grass, among weeds or, less often, in a low bush and is well fixed to the supporting grass-stems or stalks. Occasionally the nest is quite pendent but, more usually, one or more of the stalks are wound into the base and sides as well. The eggs number four and in colour are a brilliant glossy brick-red, normally unicoloured, but, exceptionally, with a darker ring or cap at the larger end. Forty eggs average 15.2 x 11.8 mm.: maxima 16.4 x 11.9 and 14.5 x 12.5 mm.; minima 14.2 X 11.6 and 16.1 x 11.0 mm.
Habits. This pretty little Warbler keeps almost entirely to grass-land, low bush and scrub-jungle or to reeds and elephant-grass in swamps and marshy places. Sometimes it may be found in thin secondary growth in deserted cultivation but never, I think, in heavy jungle or forest. It takes its insect diet from the leaves and grasses and also from the ground, where it is very active. On the wing it is very feeble and has the same top-heavy flight of most of the long-tailed Prinias. As a rule, it shuns observation, but in the breeding-season the male sings a cheery, but weak, little song, perched high up on some tall grass or bush top. It makes the same curious clicking noise as it moves about as do other species of this genus, possibly with its bill, more probably with its wings meeting over its back.