The Kakapo is a very large parrot, growing to a length of 64 cm. The feathers on their backs are moss-green, mottled with black chevrons, and dark brown blotches. The top of the tail has similar markings on a green-brown background. The feathers of the throat, breast and under the tail are a soft, mottled, yellow-green color. Females are usually similar to males in coloration, though slightly smaller in stature.
Immature birds are duller in coloration.
The Kakapo is the only flightless parrot in the world and its wings, while present, are small and insignificant. The sternum lacks a keel, as there is no need for a place for flight muscles to attach. The Kakapo usually holds its body in a horizontal position with the bristle feathers on its face nearly touching the ground. The diet of S. habroptilus is completely vegetarian. Because of this what they eat varies, depending on the season.