These species are big and black in colour, but there is a very wide variety in size. They weigh 3.3lbs to 5.3 kilograms. They are 70-102 centimetres, and which is 28-40 inches and its wingspan from 121-160 centimetres (48-63 inches). It has a long tail and a yellow-throated patch. The adults have white thigh patches in its breeding seasons.