The kākāpō ("kA:k@poU ; kaːkaːpɔː; : kākāpō, (Strigops habroptila), also known as the owl parrot, is a species of large, nocturnal, ground-dwelling parrots of the super-family Strigopoidea. The bird is endemic to New Zealand. Kākāpō can be up to long. They have a combination of unique traits among parrots: finely blotched yellow-green plumage, a distinct facial disc, owl-style forward-facing eyes with surrounding discs of specially-textured feathers, a large grey beak, short legs, large blue feet, relatively short wings and a short tail. It is the world's only flightless parrot, the world's heaviest parrot, and also is nocturnal, herbivorous, visibly sexually dimorphic in body size, has a low basal metabolic rate, and does not have male parental care. It is the only parrot to have a polygynous lek breeding system. It is also possibly one of the world's longest-living birds, with a reported lifespan of up to 100 years. Adult males weigh around ; the equivalent figure for females is . The anatomy of the kākāpō typifies the tendency of bird-evolution on oceanic islands. With few predators and abundant food, kākāpō exhibit island syndrome development, having a generally-robust torso physique at the expense of flight abilities, resulting in reduced shoulder- and wing-muscles, along with a diminished keel on the sternum. Like many other New Zealand bird species, the kākāpō was historically important to Māori, the indigenous people of New Zealand. It appears in Māori mythology. Heavily hunted in the past, it was used by the Māori both for its meat and for its feathers. The kākāpō is critically endangered; the total known population of living individuals is Known individuals are named, tagged and confined to four small New Zealand islands, all of which are clear of predators; however, in 2023, a reintroduction to mainland New Zealand (Maungatautari) was accomplished. Introduced mammalian predators, such as cats, rats, ferrets, and stoats almost wiped out the kākāpō. All conservation efforts were unsuccessful until the Kakapo Recovery Programme began in 1995.