Carricero de las Marquesas Septentrionales Acrocephalus percernis

A large, seemingly long-bodied warbler, mostly bright yellow with some greenish-olive above. Bill and tail long. Often perches in a flat stance, making it look banana-like. Most common in dense brush and thickets with dense tangled understory. Song is a loud and long sequence of warbled phrases and “churr” notes. Calls include harsh churring and “tchak” notes.