Screamer

Screamer, any bird of the South American family Palamedeidae, allied to the ducks and geese. There are two strong spurs on each wing. The Horned Screamer (Palamedea cornuta), rather smaller than a turkey, has blackish-brown plumage and an erectile horn on the head. The Crested Screamer (Chauna chavaria), and the Darbian Screamer (C. derbiana), have erectile feathers, but no horn. The former is domesticated and allowed to run with poultry that it may defend them from the vultures.