Their plumage is generally black and white.
Various species occur in the warmer regions of the world.
The scarlet colour is caused by an accumulation of pigment from the aquatic invertebrates that it feeds on. The sacred ibis was worshipped by the ancient Egyptians. It always appeared in Egypt at the rise of the River Nile, and was supposed to preserve the country from plagues and serpents. Numerous mummified remains of ibises, wrapped in linen, have been found at Thebes and Memphis.