Каштановоголовая пипира Thlypopsis pyrrhocoma

A skulking tanager found in dense undergrowth of humid forests and second growth often with bamboo. Males have a chestnut head with a black forehead and mask, but are otherwise gray. Females are olive-green above and gray below with a hint of rufous on the cap. The song is a very high-pitched “pseee-pseee-pseee, tweee-tweee-tweee.”