Red-billed quelea far above the bill, and the underparts may have a pink wash. There is much variability within subspecies, and some birds cannot be ascribed to a subspecies based on outward appearance alone. Because of interbreeding, specimens intermediate between subspecies may occur where the ranges of the subspecies overlap, such as at Lake Chad. The female pin-tailed whydah could be mistaken for the red-billed quelea in non-breeding plumage, since both are sparrow-like birds with conical red-coloured bills, but the whydah has a whitish brow between a black stripe through the eye and a black stripe above. Flying flocks make a distinct
Red-billed quelea and wing coverts and flight feathers have buff margins. At an age of about five months they moult again and their plumage starts to look like that of breeding adults, with a pinkish-purple bill. Different subspecies are distinguished by different colour patterns of the male breeding plumage. In the typical subspecies, "Q. quelea quelea", breeding males have a buff crown, nape and underparts and the black mask extends high up the forehead. In " Q. quelea lathamii" the mask also extends high up the forehead, but the underparts are mainly white. In "Q. quelea aethiopica" the mask does not extend