コウヨウチョウ Quelea quelea

A small, short-tailed weaver with a mottled back and a yellow or reddish bill, eye-ring, and legs. When breeding, the male develops a variable black face mask with a surrounding wash that can be rosy, buff, or cinnamon, although the face can also be whitish. Large flocks are resident and nomadic in arid savanna, grassland, and cultivated areas. In wetter years this species forms enormous flocks numbering tens of thousands, earning it the name “feathered locust.” Non-breeding Red-headed Weaver is superficially similar, but it is much larger than Red-billed Quelea, and it is mostly solitary in woodland and has an unstreaked back.