Illuminated by blue and UV light, the birds’ white and bright yellow plumage broadcasts colors that may be used in territorial disputes or for finding mates, according to the study.

These birds are olive with bright yellow throats and breasts. And their black eye mask is offset by a blurry white line that separates the face from the head. The common yellowthroat is abundant ...

Length 5". A relatively large carduelid. Breeding male: unmistakable. Body entirely bright lemon yellow with white undertail coverts. Jet black cap. Black wings with yellow lesser coverts and ...

One of the most common winter sparrows, the white-crowned typically occurs in flocks, which may involve more than 100 birds ... prominent white throat, and yellow supraloral.