An unmistakable medium-sized songbird: dark olive-green with a black head, white collar, gray “whiskers” on the face, and black-tipped tail. Namesake yellow bill is stout and slightly curved, unlike the dark thin bills of most bulbuls. Often seen perched on telephone wires, treetops, and rooftops. Forages methodically in lowland and foothill forests, gardens, and brushlands (below 1500 m). Regularly gathers in flocks, but not a common component of mixed-species flocks. Song a series of three-syllabled warbles; calls include rising “chirrup” and series of “whit” notes.