Kea | ||||||||||||||
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Conservation status | ||||||||||||||
Vulnerable (IUCN 2.3)[1] |
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Scientific classification | ||||||||||||||
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Binomial name | ||||||||||||||
Nestor notabilis Gould, 1856 |
The Kea (Nestor notabilis) is a species of parrot (family Psittacidae) found in forested and alpine regions of the South Island of New Zealand. The Kea is one of the few alpine parrots in the world, and includes carrion in an omnivorous diet consisting mainly of roots, leaves, berries, nectar and insects. Now uncommon, the Kea was once killed for bounty as it preyed on livestock, especially sheep, only receiving full protection in 1986.[2]
Kea are legendary for their intelligence and curiosity, both vital to their survival in a harsh mountain environment. Studies have shown Kea to be able to solve logical puzzles, such as pushing and pulling things in a certain order to get to food, as well as working in teams to achieve a certain objective.[3]
Most people only encounter wild Kea at South Island ski areas. The Kea are attracted by the prospect of food scraps from human habitation. Their curiosity leads them to peck and carry away unguarded items of clothing, or to pry apart rubber parts of cars - to the entertainment and annoyance of human observers. They are often described as "cheeky".
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The Kea was described by ornithologist John Gould in 1856. Its specific epithet, the Latin term notabilis, means "noteworthy".[4] The common name is from Māori, probably representing the screech of the bird. The term Kea is both singular and plural.
The genus Nestor contains three species: The Kākā (Nestor meridionalis), the Kea (N. notabilis), and the extinct Norfolk Island Kākā (N. productus). All three are thought to stem from a 'proto-Kākā', dwelling in the forests of New Zealand 15 million years ago.[5] The closest relative is most likely the Kākāpō (Strigops habroptilus).[6]
A 2005 sex chromosome spindlin DNA sequence study suggests that the Nestor species, and the Kākāpō in its own genus, comprise an ancient group that split off from all other Psittacidae before their radiation,[7] but fossil evidence seems to contradict this; 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.
The Kea (Nestor notabilis) is one of seven parrot species endemic to New Zealand. The other mainland species are the Kākā (Nestor meridionalis), the Kākāpō (Strigops habroptilus), and three species of Kākāriki: the Yellow-crowned Parakeet (Cyanoramphus auriceps), Red-crowned Parakeet (Cyanoramphus novaezelandiae) and the Orange-crowned Parakeet (Cyanoramphus malherbi). The seventh New Zealand parrot species is the Antipodes Island Parakeet (Cyanoramphus unicolor)), endemic to the subantarctic islands after which it is named.
The Kea ranges from lowland river valleys up to the alpine regions of the South Island such as Arthur's Pass and Mt. Cook National Park, closely associated throughout its range with the southern beech (Nothofagus) forests in the alpine ridge. Its notorious urge to explore and manipulate, combined with strong neophilia, makes this bird a pest for residents and an attraction for tourists. Called "the clown of the mountains", it will investigate backpacks, boots or even cars, often causing damage or flying off with smaller items.
Population estimates range from 1,000 to 5,000 individuals,[8] but its widespread distribution at low density prevents accurate estimates.[9][10] Together with local councils and runholders, the New Zealand government paid a bounty for Kea bills because the bird preyed upon lifestock, mainly sheep.[11][12] It was intended that hunters would kill Kea only on the farms and council areas that paid the bounty, but some hunted them in national parks and in Westland, where they were officially protected. More than 150,000 were killed in the hundred years before 1970, when the bounty was lifted.[13] In the 1970s the Kea received partial protection after a census counted only 5000 birds. It was not fully protected until 1986, when farmers gave up their legal right to shoot any Kea that tampered with property or livestock. In exchange, the government agreed to investigate any reports of problem birds and have them removed from the land.[9]
In the wild, undocumented, but estimated to be 15 years.[14]
At least one observer has reported that the Kea is polygamous, with one male attached to multiple females. The same source noted that there was a surplus of females.[15]
Keas are social and live in groups of up to 13 birds.[16] Isolated individuals do badly in captivity but respond well to mirror images.[17]
In one study, nest sites occur at a density of 1 per 4.4km².[10] The breeding areas are most commonly in Southern Beech (Nothofagus sp.) forests, located on steep mountain sides. Breeding at heights of 1600m above sea level and higher, it is one of the few parrot species in the world to regularly spend time above tree line. Nest sites are usually positioned on the ground underneath large beech trees, in rock crevices or dug burrows between roots. They are accessed by tunnels leading back 1m to 6m into a larger chamber, which is furnished with lichens, moss, ferns and rotting wood. The laying period starts in January and reaches into July.[18] 2-4 white eggs are laid, with an incubation time of around 21 days.[19]
An omnivore, the Kea feeds on more than 40 plant species (Tab. 1), beetle larva, other birds (including shearwater chicks) and mammals (including sheep and rabbits).[16][3] The Kea has also taken advantage of human garbage and "gifts" of food.[20] In captivity, the bird is fond of butter, nuts, apples, carrots, grapes, mangoes, figs, bread, dairy products, ground meat and pasta.
There had been a long-running controversy about whether the Kea preys on sheep, with the earliest reports appearing in 1867. An article by naturalist G.R. Marriner in 1906, describing substantial anecdotal evidence of these attacks, became the accepted view of the bird's habits.[11] Several prominent members of the scientific community concluded that the rumours were true, although others were not convinced. However, in 1962 animal specialist J.R. Jackson concluded that the bird may attack sick or injured sheep, especially if it mistook them for dead, but that it was not a significant predator.[21] Finally, in 1993, its nocturnal assaults were captured on video,[3], proving that at least some Kea will attack and feed on healthy sheep. The video confirmed what many scientists had long suspected, that the Kea uses its powerful curved beak and claws to rip through the layer of wool and eat the fat from the back of the animal. Though the Kea does not directly kill the sheep, death can result from blood poisoning or accidents suffered by animals trying to escape.
The Kea has also been observed breaking opened shearwater nests to feed on the chicks after hearing the chicks in their nests.
The Kea has been observed feeding on the following plants:[16]
Fruits: | Astelia nervosa | Leaves and buds: | Euphrasia zelandica |
Coprosma pseudopunctata | Gentiana bellidifolia | ||
Coprosma pumila | Gentiana spenceri | ||
Coprosma serrulata | Gnaphalium traversii | ||
Cyathodes colensoi | Hebe pauciramosa | ||
Cyathodes fraseri | Hebe vernicosa | ||
Caultheria depressa | Lagenophora petiolata | ||
Muehlenbeckia axillaris | Nothofagus solandri var cliff. | ||
Pentachondra pumila | |||
Podocarpus nivalis | |||
Seeds: | Aciphylla colensoi | Flowers: | Celimisia coriacea |
Aciphylla ferox | Celimisia discolor var ampla | ||
Aciphylla monroi | Celimisia spectabilis var ang. | ||
Astelia nervosa | Cotula pyrethrifolia | ||
Hebe ciliolata | Gentiana bellidifolia | ||
Pimelea oreophila | Gentiana patula | ||
Pittosporum anomalu | Gentiana spenceri | ||
Plantago raoulia | Haastia pulvinaris | ||
Luzula campestris | |||
Roots: | Anisotome pilifera | Entire plant: | Anisotome aromatica var arom. |
Celmisia coriacea | Ourisia sessilifolia | ||
Gingidium montanum | Ourisia caespitosa | ||
Notothlaspi australe | Ourisia macrophylla | ||
Ranunculus insignis |