The Baya Weaver is widespread in the Indian Subcontinent and South East Asia. Large flocks are found in grasslands, farmlands, scrub and secondary growth. Though widespread, they are not generally migratory and move about locally depending upon food and habitat factors.
Looking like, and often mistaken for sparrows, sexes are alike except during the breeding season during monsoons when the males have a bright yellow crown, dark brown mask, blackish brown bill, upper parts are dark brown streaked with yellow, with a yellow breast and cream buff below.
Baya Weavers make spectacular nests, very well planned with two or three ‘rooms’ inside them. The nests are partially built before the males begin to display to passing females by flapping their wings and calling while hanging from their nests. The females inspect the nest and signal their acceptance of a male. Once a male and a female are paired, the male goes on to complete the nest by adding the entrance tunnel. Males are almost solely in charge of nest building, though their female partners may join in giving the finishing touches, particularly on the interiors.
Here is an interesting anecdote from British India:
The baya is like a wild sparrow but yellow. It is extremely intelligent, obedient and docile. It will take small coins from the hand and bring them to its master, and will come to a call from a long distance. Its nests are so ingeniously constructed as to defy the rivalry of clever artificers.
— Āīn (trans. Jarrett), iii. 122. (ca. 1590) quoted in the Hobson Jobson