This huge ibis has a large, curved bill and a distinctive repeated, loud, ringing call sounding like ‘a-leurk a-leurk’, mainly used at dawn and dusk. The adult is dark with a naked, grey head and upper neck. There are dark bands across the back of the head and shoulder area and the pale silvery-grey wing tips also have black crossbars. The beak is yellowish-brown, the legs are orange, and the eyes are dark red. Juveniles have short black feathers on the back of the head down to the neck. Their bills are shorter and their eyes are brown.