Kakapo

The kākāpō (Māori: [ˈkaːkaːpɔː]; pl.: kākāpō; Strigops habroptilus), sometimes known as the owl-parrot, is a species of large, nocturnal, ground-dwelling parrot of the superfamily Strigopoidea. It is endemic to New Zealand. Kākāpō can be up to 64 cm (25 in) long. They have a combination of unique traits among parrots: finely blotched yellow–green plumage, a distinct facial disc, owl-like 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 ...

Before the arrival of humans, the kākāpō was widely distributed throughout both main islands of New Zealand. Although it may have inhabited Stewart Island before human arrival, it has not been found in the extensive fossil collections from there. Kākāpō lived in a variety of habitats, including tussocklands, scrublands and coastal areas. It also inhabited forests dominated by podocarps (rimu, mataī, kahikatea, tōtara), beeches, tawa, and rātā. In Fiordland, areas of avalanche and slip debris with regenerating and heavily fruiting vegetation – such as five finger, wineberry, bush lawyer, tutu, hebes, and coprosmas – became known as "kākāpō gardens". The kākāpō is considered to be a "habitat generalist". Though they are now confined to islands free of predation, they were once able to live in nearly any climate present on the islands of New Zealand. They survived dry, hot summers on the North Island as well as cold winter temperatures in the sub-alpine areas of Fiordland. Kākāpō seem to have preferred broadleaf or mountain beech and Hall's tōtara forest with mild winters and high rainfall, but the species was not exclusively forest-dwelling.

New Zealand

The beak of the kākāpō is adapted for grinding food finely. For this reason, the kākāpō has a very small gizzard compared to other birds of their size. It is entirely herbivorous, eating green shoots, leaf buds, roots, rhizomes and tubers of native plants, as well as seeds, nuts, berries, other fruits, pollen, moss, fungi and even the bark and sapwood of trees. A study in 1984 identified 25 plant species as kākāpō food. It is specifically fond of the fruit of the rimu tree, and will feed on it exclusively during seasons when it is abundant. The kākāpō strips out the nutritious parts of the plant with its beak, leaving a ball of indigestible fibre. These little clumps of plant fibres are a distinctive sign of the presence of the bird. The kākāpō is believed to employ bacteria in the fore-gut to ferment and help digest plant matter. Kākāpō diet changes according to the season. The plants eaten most frequently during the year include some species of Lycopodium ramulosum, Lycopodium fastigium, Schizaea fistulosa, Blechnum minus, Blechnum procerum, Cyathodes juniperina, Dracophyllum longifolium, Olearia colensoi and Thelymitra venosa. Individual plants of the same species are often treated differently. Kākāpō may forage heavily in certain areas, leaving, on occasion, more than 30 droppings and conspicuous evidence of herbivory. These areas, which are mostly dominated by mānuka and yellow silver pine, range from 100 – 5,000 sq. metres (1,076 – 53,820 sq. feet) per individual. Preserved coprolites of kākāpō have been studied to obtain information on the historic diet of the bird. This research has identified 67 native plant genera previously unrecorded as food sources for kākāpō including native mistletoes as well as Dactylanthus taylorii.

The kākāpō is primarily nocturnal; it roosts under cover in trees or on the ground during the day and moves around its territories at night. Though the kākāpō cannot fly, it is an excellent climber, ascending to the crowns of the tallest trees. While climbing, it frequently uses its wings for balance. It can also "parachute" – descending by leaping and spreading its wings; in this way it may travel a few metres at a steep downward angle of less than 45 degrees. Lighter females can perform short glides across gaps of 3–4 m. With only 3.3% of its mass made up of pectoral muscle, it is no surprise that the kākāpō cannot use its wings to lift its heavy body off the ground. Because of its flightlessness, it has very low metabolic demands in comparison to flighted birds. It is able to survive easily on very little or on very low quality food sources. Unlike most other bird species, the kākāpō is entirely herbivorous, feeding on fruits, seeds, leaves, stems, and rhizomes. When foraging, kākāpō tend to leave crescent-shaped wads of fibre in the vegetation behind them, called "browse signs". Having lost the ability to fly, it has developed strong legs. Locomotion is often by way of a rapid "jog-like" gait by which it can move several kilometres. A female has been observed making two return trips each night during nesting from her nest to a food source up to 1 km (0.6 mi) away and the male may walk from its home range to a mating arena up to 5 km (3 mi) away during the mating season (October–January). Young birds indulge in play fighting, and one bird will often lock the neck of another under its chin. The kākāpō is curious by nature and has been known to interact with humans. Conservation staff and volunteers have engaged extensively with some kākāpō, which have distinct personalities. Despite this, kākāpō are solitary birds. The kākāpō was a very successful species in pre-human New Zealand, and was well adapted to avoid the birds of prey which were their only predators. As well as the New Zealand falcon, there were two other birds of prey in pre-human New Zealand: Haast's eagle and Eyles' harrier. All these raptors soared overhead searching for prey in daylight, and to avoid them the kākāpō evolved camouflaged plumage and became nocturnal. When a kākāpō feels threatened, it freezes, so that it is more effectively camouflaged in the vegetation its plumage resembles. Kākāpō were not entirely safe at night, when the laughing owl was active, and it is apparent from owl nest deposits on Canterbury limestone cliffs that kākāpō were among their prey. Kākāpō defensive adaptations were no use, however, against the mammalian predators introduced to New Zealand by humans. Birds hunt very differently from mammals, relying on their powerful vision to find prey, and thus they usually hunt by day. Mammalian predators, in contrast to birds, often hunt by night, and rely on their sense of smell and hearing to find prey; a common way for humans to hunt kākāpō was by releasing trained dogs. The kākāpō's adaptations to avoid avian predation have thus been useless against its new enemies, and the reason for its massive decline since the introduction of dogs, cats and mustelids (see Conservation: Human impact). Its intelligence commands respect, and its helplessness sympathy, while its genial nature endears it to all who know it well. It repays kindness with gratitude, and is as affectionate as a dog, and as playful as a kitten.

Life expectancy about 59 years.

Kākāpō are the only flightless bird that has a lek breeding system. Males loosely gather in an arena and compete with each other to attract females. Females listen to the males as they display, or "lek". They choose a mate based on the quality of his display; they are not pursued by the males in any overt way. No pair bond is formed; males and females meet only to mate. During the courting season, males leave their home ranges for hilltops and ridges where they establish their own mating courts. These leks can be up to 5 kilometres (3 mi) from a kākāpō's usual territory and are an average of 50 metres (160 ft) apart within the lek arena. Males remain in the region of their court throughout the courting season. At the start of the breeding season, males will fight to try to secure the best courts. They confront each other with raised feathers, spread wings, open beaks, raised claws and loud screeching and growling. Fighting may leave birds with injuries or even kill them. Mating occurs roughly every two to four years in years of heavy rimu fruiting. In mating years, males may make "booming" calls for 6–8 hours every night for more than four months. Each court consists of one or more saucer-shaped depressions or "bowls" dug in the ground by the male, up to 10 centimetres (4 in) deep and long enough to fit the half-metre length of the bird. The kākāpō is one of only a handful of birds in the world which actually constructs its leks. Bowls are often created next to rock faces, banks, or tree trunks to help reflect sound: the bowls themselves function as amplifiers to enhance the projection of the males' booming mating calls. Each male's bowls are connected by a network of trails or tracks which may extend 50 metres (160 ft) along a ridge or 20 metres (70 ft) in diameter around a hilltop. Males meticulously clear their bowls and tracks of debris. To attract females, males make loud, low-frequency (below 100 Hz) booming calls from their bowls by inflating a thoracic sac. They start with low grunts, which increase in volume as the sac inflates. After a sequence of about 20 loud booms, the male kākāpō emits a high-frequency, metallic "ching" sound. He stands for a short while before again lowering his head, inflating his chest and starting another sequence of booms. The booms can be heard at least 1 kilometre (0.62 mi) away on a still night; wind can carry the sound at least 5 kilometres (3.1 mi). Females are attracted by the booms of the competing males; they too may need to walk several kilometres from their territories to the arena. Once a female enters the court of one of the males, the male performs a display in which he rocks from side to side and makes clicking noises with his beak. He turns his back to the female, spreads his wings in display and walks backwards towards her. He will then attempt copulation for 40 minutes or more. Once the birds have mated, the female returns to her home territory to lay eggs and raise the chicks. The male continues booming in the hope of attracting another female. The female kākāpō lays 1–4 eggs per breeding cycle, with several days between eggs. The nest is placed on the ground under the cover of plants or in cavities such as hollow tree trunks. The female incubates the eggs beginning after the first egg is laid, but is forced to leave the nest every night in search of food. Predators are known to eat the eggs, and the embryos inside can also die of cold in the mother's absence. Kākāpō eggs usually hatch within 30 days, bearing fluffy grey chicks that are quite helpless. The female feeds the chicks for three months, and the chicks remain with the female for some months after fledging. The young chicks are just as vulnerable to predators as the eggs, and young have been killed by many of the same predators that attack adults. Chicks leave the nest at approximately 10 to 12 weeks of age. As they gain greater independence, their mothers may feed the chicks sporadically for up to 3 months. The k…

The kākāpō was formally described and illustrated in 1845 by the English ornithologist George Robert Gray. He created a new genus and coined the binomial name Strigops habroptilus. Gray was uncertain about the origin of his specimen and wrote, "This remarkable bird is found in one of the islands of the South Pacific Ocean." The type location has been designated as Dusky Sound on the southwest corner of New Zealand's South Island. The generic name Strigops is derived from the Ancient Greek strix, genitive strigos ("owl"), and ops ("face"), while its specific epithet habroptilus comes from habros ("soft"), and ptilon ("feather"). In 1955 the International Commission on Zoological Nomenclature (ICZN) ruled that the genus name Strigops was feminine. Based on this ruling many ornithologists used the form Strigops habroptila but in 2023 James L. Savage and Andrew Digby argued that under the current ICZN rules the specific epithet should be habroptilus. This view was accepted by ornithologists and in 2024 the International Ornithological Congress Checklist and the eBird/Clements Checklist changed the spelling of the binomial name back to Strigops habroptilus. The species is monotypic, as no subspecies are recognised. The name kākāpō is Māori, from kākā ("parrot") + pō ("night"); the name is both singular and plural. "Kākāpō" is increasingly written in New Zealand English with the macrons that indicate long vowels. The correct pronunciation in Māori is [kaːkaːpɔː]; other colloquial pronunciations exist, however. These include the British English (KAH-kə-poh), as defined in the Chambers Dictionary in 2003. The kākāpō is placed in the family Strigopidae together with the two species in the genus Nestor, the kea (Nestor notabilis) and the kākā (Nestor meridionalis). The birds are endemic to New Zealand. Molecular phylogenetic studies have shown that the family Strigopidae is basal to the other three parrot families in the order Psittaciformes and diverged from them 33–44 million years ago. The common ancestor of the kākāpō and the two Nestor species diverged 27–40 million years ago. Earlier ornithologists felt that the kākāpō might be related to the ground parrots and night parrot of Australia due to their similar colouration, but this is contradicted by molecular studies; rather, the cryptic colour seems to be adaptation to terrestrial habits that evolved twice convergently. The kākāpō is a large, rotund parrot. Adults can measure from 58 to 64 cm (23 to 25 in) in length with a wingspan of 82 cm (32 in). Males are significantly heavier than females with an average weight of 2 kg (4.4 lb) compared with just 1.5 kg (3.3 lb) for females. Kākāpō are the heaviest living species of parrot and on average weigh about 400 g (14 oz) more than the largest flying parrot, the hyacinth macaw. 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. Lighter females are able to perform short glides across gaps in the canopy. Unlike many other land birds, the kākāpō can accumulate large amounts of body fat. The upper parts of the kākāpō 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 show that some birds had completely yellow colouring. The breast and flank are yellowish-green streaked with yellow. The belly, undertail, neck, and face 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 habroptila. The kākāpō has a conspicuous facial disc of fine feathers resembling the face of an owl; thus, early European set…

1977: Kākāpō rediscovered on Stewart Island 1989: Most kākāpō are removed from Rakiura to Whenua Hou and Hauturu-O-Toi 1995: Kākāpō population consists of 51 individuals; beginning of the Kakapo Recovery Programme 1999: Kākāpō removed from Hauturu 2002: A significant breeding season led to 24 chicks being hatched 2005: 41 females and 45 males, including four fledglings (3 females and 1 male); kākāpō established on Anchor Island 2009: The total kākāpō population rose to over 100 for the first time since monitoring began. Twenty-two of the 34 chicks had to be hand-reared because of a shortage of food on Codfish Island. December 2010: Death of the oldest known kākāpō, "Richard Henry", possibly 80 years old. 2012: Seven kākāpō transferred to Hauturu, in an attempt to establish a successful breeding programme. Kākāpō were last on the island in 1999. March 2014: With the kākāpō population having increased to 126, the bird's recovery was used by Melbourne artist Sayraphim Lothian as a metaphor for the recovery of Christchurch, paralleling the "indomitable spirit of these two communities and their determination to rebuild". 2016: First breeding on Anchor; a significant breeding season, with 32 chicks; kākāpō population grows to over 150 2018: After the death of 3 birds, the population reduced to 149 birds. 2019: An abundance of rimu fruit and the introduction of several new technologies (including artificial insemination and 'smart eggs') helped make 2019 the best breeding season on record, with over 200 eggs laid and 72 chicks fledged. According to the Kākāpō Recovery Team at the New Zealand Department of Conservation, this was the earliest and longest breeding season yet. Population reached 200 juvenile or older birds on 17 August 2019. 2022: The population increased to 252 birds after a productive breeding season and successful artificial insemination. 2023: Birds are reintroduced to the mainland for the first time. 2024: As of September 2024, the population had declined slightly to 243 individuals.

Fossil records indicate that in pre-Polynesian times, the kākāpō was New Zealand's third most common bird and it was widespread on all three main islands. However, the kākāpō population in New Zealand has declined massively since human settlement of the country, and its conservation status as ranked by the Department of Conservation continues to be "Nationally Critical". Since the 1890s, conservation efforts have been made to prevent extinction. The most successful scheme has been the Kākāpō Recovery Programme; this was implemented in 1995 and continues to this day. Kākāpō are absolutely protected under New Zealand's Wildlife Act 1953. The species is also listed under Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) meaning international export/import (including parts and derivatives) is regulated.

The kākāpō was formally described and illustrated in 1845 by the English ornithologist George Robert Gray. He created a new genus and coined the binomial name Strigops habroptilus. Gray was uncertain about the origin of his specimen and wrote, "This remarkable bird is found in one of the islands of the South Pacific Ocean." The type location has been designated as Dusky Sound on the southwest corner of New Zealand's South Island. The generic name Strigops is derived from the Ancient Greek strix, genitive strigos ("owl"), and ops ("face"), while its specific epithet habroptilus comes from habros ("soft"), and ptilon ("feather"). In 1955 the International Commission on Zoological Nomenclature (ICZN) ruled that the genus name Strigops was feminine. Based on this ruling many ornithologists used the form Strigops habroptila but in 2023 James L. Savage and Andrew Digby argued that under the current ICZN rules the specific epithet should be habroptilus. This view was accepted by ornithologists and in 2024 the International Ornithological Congress Checklist and the eBird/Clements Checklist changed the spelling of the binomial name back to Strigops habroptilus. The species is monotypic, as no subspecies are recognised. The name kākāpō is Māori, from kākā ("parrot") + pō ("night"); the name is both singular and plural. "Kākāpō" is increasingly written in New Zealand English with the macrons that indicate long vowels. The correct pronunciation in Māori is [kaːkaːpɔː]; other colloquial pronunciations exist, however. These include the British English (KAH-kə-poh), as defined in the Chambers Dictionary in 2003. The kākāpō is placed in the family Strigopidae together with the two species in the genus Nestor, the kea (Nestor notabilis) and the kākā (Nestor meridionalis). The birds are endemic to New Zealand. Molecular phylogenetic studies have shown that the family Strigopidae is basal to the other three parrot families in the order Psittaciformes and diverged from them 33–44 million years ago. The common ancestor of the kākāpō and the two Nestor species diverged 27–40 million years ago. Earlier ornithologists felt that the kākāpō might be related to the ground parrots and night parrot of Australia due to their similar colouration, but this is contradicted by molecular studies; rather, the cryptic colour seems to be adaptation to terrestrial habits that evolved twice convergently.