(1024) Uroloncha striata acuticauda (Hodgs.).
THE HIMALAYAN WHITE-BACKED MUNIA.
Uroloncha striata acuticauda, Fauna B. I., Birds, 2nd ed, vol. iii, p. 84.
The Himalayan form of White-backed Munia extends all through the Sub-Himalayan Terai between the foot-hills and 4,000 feet from Garhwal to Eastern Assam. Thence it is found throughout Northern Burma to the South Shan States and Northern Siam. This is a very common Munia in Assam, breeding from the foot-hills up to 5,000 feet but most numerous between 1,500 and 3,000 feet.
The birds breed both in open country, light scrub-jungle, secondary growth and even in the interior of deep humid forest. One of the first nests I ever took was taken at nearly 4,000 feet in the warm, humid valley of the Laisang River, built in a low bush beside a foot-track leading from one village to another, and at least half a mile from any open space. The trees were very lofty but there was much green undergrowth. A very favourite site is a cotton-bush, or other low bush growing in cotton-fields which are surrounded by forest ; the light growth which springs up the first year cultivation is abandoned is algo often built in, while I have seen nests situated in orange and other fruit-trees in my garden and orchards, though this is rare. Hodgson says that they sometimes place their nests “either among the spiny leaves of the palm-trees or the thick interlaced branches of the lesser hamboos.” Other birds sometimes make their nests low down and well inside the clumps of the giant bamboo. The most unusual site recorded was one taken by Irwin in Hill Tippera “composed of fine grass-stems placed in a half-open hole in a low hank.”
As a rule the nest is placed low down between three and four feet from the ground, but I have found some in brambles a few inches above it and others as much as 20 feet up in small trees, bamboo clumps etc.
The nest is the usual untidy ball of grass, measuring anything between 5 by 5 inches to 10 by 10 inches when round and between 6 by 4.1/2 to 10 by 7 inches when oval. Personally I have never seen anything but grass used in their construction except a few bamboo leaves incorporated in the base of the nests built in bamboo-clumps. The grass used is very fine, often stems with the flowering ends attached which are not thicker than a needle, the ends sticking out everywhere and projecting from the loosely built round entrance, so far all round that they sometimes form a rough tube.
Hodgson says that “the nests are composed of grass, fibres or the leaves of Pinus longifolia” ; Gammie says of the nests found by him in Sikkim that the outside was of coarse grass, the inner of fine, and of one he writes that bamboo-leaves were mixed with the grass. The materials are very loosely interwoven and, as a rule, do not embrace the supporting twigs, the nest being carelessly pushed in among them ; there is no regular lining, the line grass-ends being used both inside and out, the flowering ends protruding from the entrance. I have seen more than one nest in which it was difficult, to say really which was the entrance, the birds apparently forcing their way through the side where it was most loosely woven. I have seen nothing similar to this in the nest of any other Munia or, indeed, of any other bird.
The breeding season is principally from the middle of May to the and of August, but eggs may be found in almost every month of the year. I have taken fresh eggs from the 3rd March to the 30th September and Gammie saw half-fledged young in November.
The eggs number five to seven in a full clutch.
One hundred eggs average 15.3 x 10.9 mm. : maxima 16.9 x 11.0 and 15.5 x 11.5 mm. ; minima 13.1 x 10.4 and 14.5 x 19.9 mm. A pigmy egg in a clutch of seven measures only 9.9 x 7.3 mm.
Both birds build the nest, which takes anything from four to eight days to construct, according to whether the hen is ready to lay OR not. Both birds also incubate, very often in company, for the ten days required, and both feed the young. These, however, are not fed, as Hodgson and Gammie thought, with grain and seeds, but with soft insects, A pair I watched were bringing in practically nothing but tiny little green caterpillars and a few spiders. After the young are fledged they and their parents use the nest for a long time for sleeping in.
I have often seen this Munia, as well as other species, collecting material for their nests and all seem to work in the same way. First they nip through a blade or stem of grass to the depth and width desired and then work up a small bit sufficient to give them a good hold with the beak ; this obtained, they give it a quick jerk and fly straight up, stripping the shred for some inches up the stem or along the leaf. By another species of Munia some patches of lemon-grsss in my garden were annually almost destroyed in this way by the birds, but their nests, built in the trellis of my verandah, were very sweet-smelling little homes.
1024. Uroloncha striata aeuticauda
(1024) Uroloncha striata acuticauda (Hodgs.).