Although little is known about the breeding habits of the grey-headed warbler, species in the Parulidae family, also known as New World warblers, are all believed to have similar reproductive behaviours (5) (6). The male and female usually remain pair-bonded throughout the breeding season. Three eggs are typically produced per clutch, although the number of eggs laid varies according to the amount of food that is available. The incubation period usually lasts 12 days, and during this period the female stays with the eggs while the male provides food (2). The breeding season for the grey-headed warbler begins in May and July, and juveniles fledge in August (3).
The nest of the grey-headed warbler is shaped like a domed cup, and has a side entrance. It is built mainly with bamboo leaves and palm material and is usually found approximately 1.5 metres above the ground (4).
Like other species of New World warbler, the grey-headed warbler feeds mainly on insects (2) and other invertebrates (4). Its thin, pointy bill is well adapted to foraging for its small prey, and it may also forage for seeds and berries. This species is elusive, and will flit at high speed from branch to branch (2).