Kakapo

The Kakapo (Māori: kākāpō, meaning night parrot), Strigops habroptilus (from the Greek strix, genitive strigos: owl and opsis: face; and habros: soft, and ptilon: feather), also called owl parrot, is a species of nocturnal parrot with finely blotched yellow-green plumage endemic to New Zealand. It has a distinct facial disc of sensory, vibrissa-like feathers, a large grey beak, short legs, large feet, and wings and a tail of relatively short length. A certain combination of traits makes it unique among its kind—it is the world's only flightless parrot, the heaviest parrot, nocturnal, herbivorous, visibly sexually dimorphic in body size, has a low basal metabolic rate, no male parental care, and is the only parrot to have a polygynous lek breeding system. It is also possibly one of the world's longest-living birds. Its anatomy typifies the tendency of bird evolution on oceanic islands with few predators and abundant food: accretion of thermodynamic efficiency at the expense of flight abilities, reduced wing muscles, a diminished keel on the sternum, a generally robust physique.

Kakapo are critically endangered; only 91 living individuals are known, all of which have been given names.The ancestral Kakapo migrated to the islands of New Zealand in prehistory; in the absence of mammalian predators, it lost the ability to fly. Because of Polynesian and European colonisation and the introduction of predators such as cats, rats, and stoats, most of the Kakapo were wiped out. Conservation efforts began in the 1890s, but they were not very successful until the implementation of the Kakapo Recovery Plan in the 1980s. As of November 2005, surviving Kakapo are kept on four predator-free islands, Maud, Chalky (Te Kakahu), Codfish (Whenua Hou) and Anchor islands, where they are closely monitored. Two large Fiordland islands, Resolution and Secretary, have been the subject of large-scale ecological restoration activities to prepare self-sustaining ecosystems with suitable habitat for the Kakapo.

The conservation of the Kakapo has made the species well known. Many books and documentaries detailing the plight of the Kakapo have been produced in recent years, one of the earliest being Two in the Bush, made by Gerald Durrell for the BBC in 1962. Two of the most significant documentaries, both made by NHNZ, are Kakapo - Night Parrot (1982) and To Save the Kakapo (1997). The BBC's Natural History Unit also featured the Kakapo, including a sequence with Sir David Attenborough in The Life of Birds. It was also one of the endangered animals that Douglas Adams and Mark Carwardine set out to find for the radio series and book Last Chance to See.

The Kakapo, like many other bird species, has historically been important to the Māori, the indigenous people of New Zealand, appearing in many of the traditional legends and folklore.

Kakapo are large, rotund parrots; males measure up to 60 centimetres (24 in) and weigh between 2 and 4 kilograms (4.5–9 lb) at maturity.Kakapo are unable to fly, having short wings for their size and lacking the pronounced keel bone (sternum) that anchors the flight muscles of other birds. They use their wings for balance, support, and to break their falls when leaping from trees. Unlike other land birds, Kakapo can accumulate large amounts of body fat to store energy making them the heaviest parrot.

The upper parts of the Kakapo have yellowish moss-green feathers barred or mottled with black or dark brownish grey, blending well with native vegetation. Individuals may have strongly varying degrees of mottling and colour tone and intensity — museum specimens have shown that some birds had completely yellow colouring. The breast and flanks are yellowish-green streaked with yellow. Their bellies, undertail, necks and faces are predominantly yellowish, streaked with pale green and weakly mottled with brownish-grey.

Because the feathers do not need the strength and stiffness required for flight, they are exceptionally soft, giving rise to the specific epithet habroptilus. Kakapo have a conspicuous facial disc of fine feathers, resembling the face of an owl; thus, early European settlers called it the "owl parrot". Their beaks are surrounded by delicate vibrissa or "whiskers", which they use to sense the ground for navigation as they walk with their heads lowered. The mandible is mostly ivory-colored, with part of the upper mandible being bluish-grey. The eyes are dark brown. Kakapo feet are large, scaly, and, as in all parrots, zygodactyl (two toes face forward and two backward). They have pronounced claws particularly useful for climbing. The ends of their tail feathers often become worn from being continually dragged on the ground.

Females are easily distinguished from males due to some notable differences: they have a more narrow and less domed head, their beaks are narrower and proportionally longer, their ceres and nostrils smaller, their legs and feet more slender and pinkish grey, and their tails are proportionally longer. While their plumage color is not very different to that of males, the toning is more subtle, with less yellow and mottling. They tend to be more resistant and aggressive than males when handled. Nesting females are also distinguished by a brood patch on the bare skin of the belly.

Like many parrots, Kakapo have a variety of calls. In addition to the booms (see below for a recording) and chings of their mating calls, they often skraark to announce their location to other birds.

Kakapo have a well-developed sense of smell, which complements their nocturnal lifestyle. They can discriminate among odours while foraging; a behaviour reported for only one other parrot species. One of the most striking characteristics of Kakapo is their pleasant and powerful odour, which has been variously described as musky, honey-like or fruity.Given the Kakapo's well-developed sense of smell, this scent may be a social chemosignal. The smell often alerts predators to the largely defenseless Kakapo.

Classification

The Kakapo has so many unusual features that it was initially placed in its own family, Strigopidae. However, it is now recognised as a member of the parrot family, Psittacidae. Its distinctiveness is highlighted by its classification in its own genus, Strigops; and tribe, Strigopini, in the subfamily Psittacinae. Some maintain the Kakapo in a subfamily of its own, Strigopinae.

Earlier ornithologists felt the Kakapo may be related to the Ground Parrot and Night Parrot of Australia; others pointed to the Nestorini tribe. A 2005 sex chromosome spindlin DNA sequence study confirmed affinities with the genus Nestor, which contains the Kākā and the Kea. The molecular data further suggests that the two Nestor species, and the Kakapo in its own genus, comprise an ancient group that split off from all other Psittacidae before their radiation, but fossil evidence seems to contradict this^{[citation needed]}; given the violent geological history of New Zealand (see, for example, Taupo Volcanic Zone), other explanations such as episodes of genetic drift seem better supported by evidence.