The kākāpō (from the Māori: 'kākāpō', lit. 'night parrot'), also called owl parrot, is a species of large, flightless, nocturnal, ground-dwelling parrot of the super-family "Strigopoidea", endemic to New Zealand. The 'kākāpō' is critically endangered; the total known adult population is 201 living individuals, all of which are named and tagged, confined to four small islands off the coast of New Zealand that have been cleared of predators. A combination of traits makes it unique among parrots: it is the world's only flightless parrot and the world's heaviest parrot.

The kākāpō cannot fly, having relatively short wings for its size and lacking the keel on the sternum (breastbone), where the flight muscles of other birds attach. It uses its wings for balance and to break its fall when leaping from trees. Unlike many other land birds, the kākāpō can accumulate large amounts of body fat.

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