Overview

Brief Summary

Biology

The takahe feeds mainly on the leaf bases and seeds of tussocks and other grasses. They occasionally take invertebrates, particular during the chick rearing period and the Fiordland birds will feed on the rhizomes of the summer-green fern hypolepis during winter (6). It is a monogamous breeder (2); nests are raised bowl-like piles of grass and are built after October when the snow begins to melt (4). A clutch can contain between one and three buff-coloured blotchy eggs (2), which hatch after about 30 days of incubation (4). Both parents incubate the egg and then share the feeding duties, which can last for up to three months. It is typical that just one chick per clutch survives the first winter (4). This species is long-lived, possibly as long as 14 to 20 years (3).
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Description

This unique flightless bird is roughly the size of a hen, making it the world's largest rail. It has a stocky body with stout red legs, and is brightly coloured with a large robust red bill and attractive green and blue plumage (4). It has small wings (4), which are used in courtship and aggressive displays (5). The call is a slow and deep 'coo-eet' and the alarm call is a deep 'oomf' (3). Chicks have black down and a black beak (5).
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Distribution

South Island takahe are endemic to New Zealand's South Island. Following conservation and reintroduction efforts South Island takahe have been introduced to the islands of Tiritiri Matangi, Kapiti, Mana, Maud, and Rarotoka, off the coast of New Zealand's South Island.

Biogeographic Regions: australian (Native )

Other Geographic Terms: island endemic

  • Wallace, G. 2002. The Takahe: Fifty Years of Conservation Management and Research. The Auk, 119/1: 291-293.
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Range Description

Porphyrio hochstetteri is endemic to New Zealand. Subfossils indicate that it was once widespread in the North and South Islands, but when "rediscovered" in 1948, it was confined to the Murchison Mountains in Fiordland (c.650 km2) (Bunin et al. 1997), and numbered just 250-300 birds (Heather and Robertson 1997). Having declined to its lowest point in the 1970s and 1980s, this population has fluctuated between 100 and 160 birds for the last 20 years (Maxwell 2001) and is thought to be at carrying capacity (Greaves 2007). A captive-rearing programme was initiated in 1985, with the aim of raising populations for translocation to predator-free islands. Translocated populations (1984-1991) now exist on four offshore islands - Kapiti, Mana, Tiritiri Matangi and Maud - but have increased only slowly, with 55 adults in 1998 (Eason and Willans 2001), due to low hatching and fledging rates related to the level of inbreeding of the female of a given pair (Bunin et al. 1997, Jamieson et al 2003). The population on Tiritiri Matangi and other small islands may be close to carrying capacity (Baber and Craig 2003).

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Range

The takahe is endemic to New Zealand, and was once widespread in both the North and South Islands. It was thought to be extinct for around 50 years (6), before being 'rediscovered' in 1948 in the Murchison Mountains of Fiordland in the South Island (3). Individuals have been introduced to the five offshore islands of Tiritiri Matangi, Kapiti, Mana, Maud and Rarotoka (6).
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Physical Description

Morphology

South Island takahe are large, flightless rails. South Island takahe are very colorful, with deep to peacock-blue heads, breasts, necks, and shoulders. The wings and back are olive-green and blue. The bill is large and red, as is the shield. South Island takahe also have large, powerful, red legs and feet. Young South Island takahe are deep blue to black at hatching but quickly take on the coloration of adults. There is little sexual dimorphism, although males average slightly larger in mass.

Average mass: Male 2.7 Female 2.3 kg.

Average length: 63 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike; male larger

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Ecology

Habitat

Mainland populations can be found in alpine tussocks grasslands and sub-alpine shrublands. Island populations live in modified grasslands.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; scrub forest

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Habitat and Ecology

Habitat and Ecology
It originally occurred throughout forest and grass ecosystems. Today it is restricted to alpine tussock grasslands on the mainland and feeds primarily on juices from the bases of snow tussock and a species of fern rhizome. It eats introduced grasses on the islands. It usually lays two eggs. Chicks can begin breeding at the end of their first year, but usually start in their second. It is long-lived, probably 14-20 years (Heather and Robertson 1997).


Systems
  • Terrestrial
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Mainland populations prefer alpine tussock grasslands although they are also found in forest and sub-alpine shrublands. Island populations are found mainly on modified grassland habitat (6).
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Trophic Strategy

South Island takahe primarily consume the leaf bases and seeds of native tussock grasses, including broad leafed snow tussock (Chionochloa rigida), mid-ribbed snow tussock (Chionochloa pallens) and curled snow tussock (Chionochloa crassiuscula). They occasionally take insects as well, especially when raising young. They also eat rhizomes of native ferns.

Animal Foods: insects

Plant Foods: leaves; roots and tubers; seeds, grains, and nuts

Primary Diet: herbivore (Folivore )

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Associations

South Island takahe numbers are exceptionally low, so their ecosystem impacts are very small. They do impact vegetation communities through their grazing.

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South Island takahe do not have any native predators. Populations have declined as a result of anthropogenic changes such as habitat destruction and modification, hunting, and the introduction of mammalian predators and competitors, including dogs, red deer, and stoats.

Known Predators:

  • Baber, M., J. Craig. 2003. Home land range and carrying capacity of the South Island takahe (Porphyrio hochstetteri) on Tiritiri Matagni Island. Notornis, 50: 67-74. Accessed April 10, 2008 at www.google.com/scholar.
  • Jamieson, I., C. Ryan. 2000. Increased egg infertility associated with translocating inbred takahe (Porphyrio hochstetteri) to island refuges in New Zealand. Biological Consevation, 94: 107-114. Accessed April 02, 2008 at www.google.com/scholar.
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Life History and Behavior

Behavior

There is little available information on communication of Porphyrio hochstetteri at this time. Visual and tactile cues are used in mating.

Communication Channels: visual ; tactile

Perception Channels: visual ; tactile ; acoustic ; chemical

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Life Expectancy

Very little is known about South Island takahe lifespan in the wild. Sources estimate they can live between 14 and 20 years in the wild. In captivity South Island takahe have lived up to 20 years.

Range lifespan

Status: captivity:
20 (high) years.

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Reproduction

Mate selection involves several courtship behaviors. Duetting and neck-pecking, of both sexes, are the most common behaviors. Following courtship, the female solicits the male by positioning her back toward the male, spreading her wings, and putting her head down. Allopreening and copulation is then done by the male.

Mating System: monogamous

Breeding occurs following the New Zealand winter, ending sometime in October. A deep, bowl-shaped nest is constructed of fine grass. Females lay a clutch of 1 to 3 eggs that hatch after about 30 days of incubation. Different survival rates have been reported, but on average only one chick will survive to adulthood.

Breeding interval: Southern takahe breed once a year.

Breeding season: The breeding season occurs following the New Zealand winter, in October.

Range eggs per season: 1 to 3.

Average eggs per season: 1.

Average time to hatching: 30 days.

Average fledging age: 3 months.

Average time to independence: 1 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous

South Island takahe pairs, when not incubating eggs, are generally seen in close proximity to each other. In contrast a breeding pair is rarely together during incubation, so it is assumed that one bird is always on the nest. Females incubate significantly more during the day and males more at night. Post-hatch observations suggest that both sexes spend similar amounts of time feeding the young. The young are fed until they are about 3 months old, at which time they become independent.

Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)

  • Ryan, C. 1997. Observations on the Breeding Behaviors of the Takahe (Porphyrio mantelli) on Manu Island. Nortonis, 44: 233-240. Accessed April 15, 2008 at www.google.com/scholar.
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Molecular Biology and Genetics

Molecular Biology

Barcode data: Porphyrio hochstetteri

The following is a representative barcode sequence, the centroid of all available sequences for this species.


There is 1 barcode sequence available from BOLD and GenBank.

Below is the sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.

See the BOLD taxonomy browser for more complete information about this specimen.

Other sequences that do not yet meet barcode criteria may also be available.

AATCGATGACTATTCTCAACCAACCACAAAGATATCGGAACACTCTATCTCATCTTCGGCGCATGAGCCGGCATAATTGGCACCGCTCTC---AGCCTCCTTATCCGAGCAGAGCTAGGACAACCAGGCAGCCTATTAGGGGAT---GACCAAATCTACAATGTAATTGTCACCGCACATGCCTTTGTAATAATCTTTTTTATAGTAATACCGGTCATAATCGGCGGATTTGGCAACTGATTAGTACCCCTAATA---ATCGGAGCCCCAGACATGGCATTCCCACGCATAAACAACATAAGCTTCTGACTCCTTCCCCCGTCCTTCCTACTACTATTAGCATCCTCCACAGTAGAAGCAGGGGCAGGTACAGGCTGAACAGTCTACCCCCCACTAGCAGGCAACCTAGCCCACGCAGGAGCCTCAGTAGATCTA---GCCATCTTCTCCCTCCATCTAGCAGGTGTCTCATCCATTCTAGGTGCCATCAACTTCATTACAACTGCCATCAACATAAAACCACCCGCTCTGTCCCAATACCAAACCCCCTTATTCGTATGATCCGTACTAATCACCGCAGTCCTACTACTACTATCACTCCCAGTACTTGCCGCA---GGCATCACCATACTACTAACCGACCGAAACCTAAACACTACATTCTTCGACCCTGCTGGCGGAGGAGACCCAATCCTATATCAACACCTCTTCTGATTCTTCGGACACCCAGAAGTCTACATCCTAATTCTTCCCGGGTTCGGAATCATCTCACATGTCGTCACTTACTACGCAGGAAAAAAA---GAACCGTTCGGCTACATAGGCATAGTATGAGCCATACTCTCCATCGGATTCCTAGGCTTCATTGTATGAGCTCACCACATATTCACAGTCGGCATAGACGTGGACACCCGAGCATACTTCACATCCGCAACAATAATCATTGCAATCCCCACCGGAATTAAAGTTTTCAGCTGATTA---GCCACA
-- end --

Download FASTA File

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Statistics of barcoding coverage: Porphyrio hochstetteri

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 2
Specimens with Barcodes: 2
Species With Barcodes: 1
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Conservation

Conservation Status

South Island takahe were thought to be extinct, with the last known specimens collected in 1898. However, careful surveys rediscovered this bird species in 1948 in the Murchison Mountains of South Island. South Island takahe are listed as endangered on the IUCN redlist. They have been the focus of major conservation and reintroduction efforts. South Island takahe populations have been established on 4 offshore islands where there are no invasive predators. Previously, hunting, loss of habitat, and introduced predators were the major factors contributing to population decline. Loss of habitat and introduced predators are still major factors, but additionally South Island takahe are threatened by lack of genetic diversity and the low fertility of these birds.

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: endangered

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IUCN Red List Assessment


Red List Category
EN
Endangered

Red List Criteria
D

Version
3.1

Year Assessed
2013

Assessor/s
BirdLife International

Reviewer/s
Butchart, S.

Contributor/s

Justification
This species is listed as Endangered because it has an extremely small, albeit slowly increasing, population. The recovery programme in place aims to establish a self-sustaining population of over 500 individuals. If the population continues to increase, the species will warrant downlisting to Vulnerable in due course.


History
  • 2012
    Endangered
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Status

Classified as Endangered (EN) on the IUCN Red List 2007 (1). Formerly Porphyrio mantelli, this species has been split into P. mantelli (extinct) and P. hochstetteri (extant) (3).
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Population

Population
The total population is currently estimated to number 227 adult birds, roughly equivalent to 340-350 individuals in total.

Population Trend
Increasing
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Threats

Major Threats
Introduced red deer Cervus elaphus competing for tussock were a major factor in the post-1940s decline (Mills and Mark 1977), while a series of unusually harsh winters appears important in the recent fluctuations (Bunin and Jamieson 1995, Bunin et al. 1997). Recent research has confirmed predation by introduced stoats Mustela erminea to also be a key threat (Crouchley 1994, Bunin and Jamieson 1996, Bunin et al. 1997, Wickes et al. 2009). Other potential competitors or predators include the introduced brush-tailed possum Trichosurus vulpecula and the threatened Weka Gallirallus australis (Department of Conservation 1997). The level of inbreeding in females appears to be related to the low hatching and fledging success exhibited by small island populations (Jamieson et al. 2003). Radio-tags have been shown to increase daily energy expenditure, which may influence mortality, particularly in hard winters (Godfrey et al. 2003). On some Tiritiri Matangi at least there is probably some predation by Swamp Harrier Circus approximans (Baber and Craig 2003). The small island populations may be close to carrying capacity (Baber and Craig 2003): on Tiritiri Matangi the 2000-2001 breeding season was largely unsuccessful, primarily due to the increase in territorial disputes among proximal family groups (Baber and Craig 2003). The small island populations have also been shown to be threatened by inbreeding depression (Grueber et al. 2010). Habitat quality on some of the islands is probably in decline as reforestation reduces the area of foraging habitat (Baber and Craig 2003). Hunting by humans is likely to have contributed historically to its decline (Wickes et al. 2009).

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When Europeans arrived in New Zealand the pressures on New Zealand's previously isolated and mammal-free fauna and flora intensified. When 'rediscovered' in 1948 just 250 to 300 takahe survived, and the population has undergone further declines since that time (3). Habitat modification and the introduction of predators such as dogs to lowland habitats were significant in the decline of takahe numbers, although these birds were probably never particularly numerous (6). More recently, harsh winters (3) and competition for grass tussocks with introduced red deer (Cervus elaphus) (6), have caused great fluctuations in the precarious populations that remain; predation by the introduced stoat (Mustela erminea) may also have taken its toll (3).
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Management

Conservation Actions

Conservation Actions
Conservation Actions Underway
Since the 1960s, deer have been controlled in the Murchison Mountains. A new mainland population in the Stuart Mountains is being established with surplus birds from the Burwood Bush Captive Rearing facility (Greaves 2007). Stoat trapping is also undertaken in the mountains (Wickes et al. 2009). Island populations of the species are managed intensively, optimising breeding success by supplementary feeding, inter-island transfers (also minimising inbreeding), and egg manipulation (primarily removal of infertile eggs to promote re-nesting) (Bunin et al. 1997). Captive-breeding efforts have increased the rate of survival to one year of age (when birds are released into the wild) by 50-60% to 90% (Maxwell and Jamieson 1997). A major review of management in 1996-1997 has been completed (Department of Conservation 1997).

Conservation Actions Proposed
Continue to monitor population and productivity trends, as well as carrying out research on captive populations. Establish a second mainland population, perhaps by fencing around the captive breeding centre at Burwood, and/or introducing the species to another area of Fiordland (Wickes et al. 2009). Promote public awareness by holding captive birds for public display and visits to islands, and through the media (Crouchley 1994). Manage the small islands as a metapopulation, with regular transfers of females between islands and periodic introductions of new breeders from the Fiordland population (Jamieson et al. 2003). Remove individuals with high mean kinship values from island population, and replace them with individuals from the Fiordland population to avert inbreeding depression (Grueber et al. 2010). Consider the introduction of birds to another island which could support a larger population. On small islands, plant clumps of native shrubs such as Coprosma spp. at 20-30 metre intervals in open grassy areas to provide cover from C. approximans. Research the viability of reintroducing bush snow-grass Chionochloa conspicua throughout the Murchison Mountains.

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Conservation

After the species was rediscovered, a special area was set up within Fiordland National Park in order to conserve this rare bird. Deer have been controlled in the area, and the habitat has started to show signs of recovery, although takahe numbers remain low (7). The New Zealand Department of Conservation's Takahe Recovery Plan began to introduce pairs to predator-free islands in 1985 (4) (7). These birds have been extensively managed and measures such as supplementary feeding and captive breeding have helped to produce successful populations (3). The Recovery Plan is currently being revised but the long-term aim is to produce two self-sustaining populations, containing 100 pairs each; one in Fiordland and one on the offshore islands and other lowland habitats (6). Takahe numbers reached a low of just 118 birds in 1982, but thanks to concerted conservation efforts the population now stands at 242 individuals (6).
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Relevance to Humans and Ecosystems

Benefits

There are no known adverse effects of Porphyrio hochstetteri on humans.

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South Island takahe represent unique adaptation towards flightlessness in island birds, especially rails. Because of their uniqueness and rarity, they support ecotourism of people interested in viewing them in introduced populations on offshore islands.

Positive Impacts: ecotourism ; research and education

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Wikipedia

Takahē

"Notornis" redirects here. For the journal, see Notornis (journal).

The takahē, Notornis, or South Island takahē (Porphyrio hochstetteri) is a flightless bird indigenous to New Zealand and belonging to the rail family. It was thought to be extinct after the last four known specimens were taken in 1898. However, after a carefully planned search effort the bird was rediscovered by Geoffrey Orbell near Lake Te Anau in the Murchison Mountains, South Island, on 20 November 1948. The specific scientific name commemorates the Austrian geologist Ferdinand von Hochstetter.

Taxonomy and systematics[edit]

A related species, the North Island takahē (P. mantelli) or mōho is extinct and only known from skeletal remains. Both forms were long assumed to be subspecies of mantelli, and were usually placed in the genus Notornis. However, it has been determined that the differences between Porphyrio and Notornis were insufficient for separating the latter, whereas the differences between the North and South Island forms justified the splitting into two species, as each evolved independently towards flightlessness.[2]

Description[edit]

The colour of the adult takahē is mainly purple-blue with a greenish back and inner wings.

The takahē is the largest living member of the Rallidae family. Its overall length averages 63 cm (24.8 in) and its average weight is about 2.7 kg (6 lbs) in males and 2.3 kg (5 lb) in females, ranging from 1.8-4.2 kg (4-9.2 lbs).[3] The standing height is around 50 cm (20 in).[4] It is a stocky bird, with reduced wings, strong legs and a massive bill.

The adult takahē is mainly purple-blue in colour, with a greenish back and inner wings. It has a red frontal shield and red-based pink bill. The legs are pink. Sexes are similar, the females being slightly smaller, but young birds have mainly pale brown plumage. Immatures have a pinkish bill with bluish cast.This is a noisy species with a loud clowp call. Contact call is easily confused with that of the weka (Gallirallus australis), but is generally more resonant and deeper.[5]

Distribution and habitat[edit]

The species is still present in the location where it was rediscovered in the Murchison Mountains. Small numbers have also been successfully translocated to five predator-free offshore islands, Tiritiri Matangi, Kapiti, Maud, Mana and Motutapu, where they can be viewed by the public. Additionally, captive takahē can be viewed at Te Anau and Mt Bruce wildlife centres. In June 2006 a pair of takahē were relocated to the Maungatautari Restoration Project. In September 2010 a pair of takahē (Hamilton and Guy) were released at Willowbank Wildlife Reserve - the first non-Department of Conservation institution to hold this species. In January 2011 two takahē were released in Zealandia, Wellington. At the beginning of 2013 there were 263 takahē accounted for, showing slow but steady growth over the previous few years.

Behaviour and ecology[edit]

Adult feeding a chick.

The takahē is a sedentary and flightless bird currently found in alpine grasslands habitats. Although it is indigenous to swamps, humans turned its swampland habitats into farmland, and the takahē was forced to move upland into the grasslands. It holds territories in the grassland until the arrival of snow, when it descends to the forest or scrub. It eats grass, shoots and insects, but predominantly leaves of Chionochloa tussocks and other alpine grass species. The takahē can often be seen to pluck a snow grass (Danthonia flavescens) stalk, taking it into one claw and eating only the soft lower parts which is a favourite food. The rest is discarded. A takahē has been recorded feeding on a paradise duckling at Zealandia. Although this behaviour was previously unknown, the related pukeko occasionally feeds on eggs and nestlings of other birds as well.

Breeding[edit]

The takahē is monogamous (with pairs remaining from 12 years to, probably, their entire lives), builds a bulky nest under bushes and scrub, and lays one to three buff eggs. It is territorial. The chick survival rate is 73-97%. Recently, human intervention has been required to maintain the breeding success of the takahē. For the success of fledgling takahē is relatively low in the wild compared to other, less threatened species, so methods such as the removal of infertile eggs from nests and the captive rearing of chicks have been introduced to manage the takahē population. The Fiordland takahē population has a successful degree of reproductive output due to these management methods: the number of chicks per pairing with infertile egg removal and captive rearing is 0.66, compared to 0.43 for regions without any breeding management.

Status and conservation[edit]

The near-extinction of the formerly widespread takahē is due to a number of factors: over-hunting, loss of habitat and introduced predators have all played a part. The introduction of red deer (Cervus elaphus) represent a severe competition for food, while the stoats (Mustela erminea) take a role as predators. The spread of the forests in post-glacial Pleistocene-Holocene has contributed to the reduction of habitat. Since the species is long-lived, reproduces slowly, takes several years to reach maturity, and had a large range that has drastically contracted in comparatively few generations, inbreeding depression is a significant problem. The recovery efforts are hampered especially by low fertility of the remaining birds. Genetic analyses have been employed to select captive breeding stock in an effort to preserve the maximum genetic diversity.[6]

Decline of takahē[edit]

Takahē were assumed to be extinct but were rediscovered by Geoffrey Orbell near Lake Te Anau in the Murchison Mountains, South Island, New Zealand on 20 November 1948. Takahē were at one time present throughout this island country, but for several reasons ceased to be found, which made many think that they were wiped out. Many reasons were cited for the failure of this flightless bird. There are two significant periods when takahē numbers declined: Pre-European and Post-European arrival.

Reasons for the pre-European decline of takahē were postulated by Williams (1962) and later supported in a detailed report by Mills et al. (1984).[7][8] They held that climate changes were the main cause of the failure in takahē before European settlement. The environmental variations before the European settlement were not suitable for takahē, and exterminated almost all of them. Survival in the altering temperature was not tolerable by this group of birds. Takahē live in alpine grasslands, but the post-glacial era destroyed those zones which caused in intense declined their numbers.

Secondly, they suggested that Polynesian settlers arriving about 800–1000 years ago, bringing dogs and Polynesian rats and hunting takahē for food, started another decline. European settlement in the nineteenth century almost wiped them out through hunting and introducing mammals such as deer which competed for food and predators (e.g. stoats) which preyed on them directly.[citation needed]

Takahē population, conservation and protection[edit]

Ringed female takahē at Kapiti Island.

After long threats of extinction, takahē now find protection in the Fiordland National park (New Zealand’s largest national park). However, the species have not made a stable recovery in this habitat since they were rediscovered in 1948. In fact the takahē population was at 400 before it was reduced to 118 in 1982 due to competition with Fiordland domestic deer. Conservationists noticed the threat deer posed to takahē survival and the national park now implements deer control by hunting by helicopter.

The rediscovery of the takahē caused great public interest in which the New Zealand government took immediate action in closing off a remote part of the Fiordland National Park to prevent the bird from being bothered. However, since the moment of rediscovery, there were different perspectives on how the bird should be conserved. According to the Forest and Bird Society, takahēs should be left to work out their own “destiny”. However, this viewpoint caused many to worry that the takahē would be incapable of making a comeback and thus become extinct like New Zealand’s native Huia bird population. Interventionists then sought to relocate the takahē “island sanctuaries” and breed them in captivity. However, no action was taken for nearly a decade due to a lack of resources and the will to avoid conflict. Fortunately, biologists from the Department of Conservation utilized their experience of designing remote island sanctuaries to establish a safe habitat for the takahē on Maud Island in the Malborough Sounds, Mana, and Kapiti Island north of Wellington off the Wairarapa Coast, and Tiritiri Matangi Island in the Hauraki Gulf. When such conservation strategies such as translocation of a species to island sanctuaries are successful, populations generally reach their carrying capacity rather quickly which can subsequently generate numerous issues with productivity and “population growth rates associated with density-dependent effects as well as increased rates of inbreeding. “ Scientists discovered through the use of logistic regression and generalized linear models that the takahē island metapopulation appears to have indeed reached carrying capacity as revealed by the increasing ratio of non-breeding to breeding adults, and declines in produced offspring. Such results pose problems regarding the maintenance of genetic diversity and thus takahē survival in the long term. Thus increasing translocation rates of takahē from the New Zealand mainland onto island sanctuaries may not be effective unless “surplus birds are removed”.

Future efforts for protection[edit]

Takahē released on Maungatautari Mountain, Waikato district, North Island in June 2006.

The original recovery strategies and goals set in the early 1980s, both long term and short term, are now well under way.

The programme to move takahē to predator-free island refuges, where the birds also receive supplementary feeding, began in 1984. Takahē can now be found on 5 small islands; Maud Island (Marlborough Sounds), Mana Island (off Wellington's west coast), Kapiti Island (off Wellington's west coast), Tiritiri Matangi Island (Hauraki Gulf) and Motutapu Island (Hauraki Gulf). The Department of Conservation also runs a captive breeding and rearing programme at the Burwood Breeding Centre near Te Anau which consists of 5 breeding pairs. Chicks are reared with minimal human contact, being fed and brooded through the use of puppets and models. The offspring of the captive birds are used for new island releases and to add to the wild population in the Murchison Mountains. The Department of Conservation also manages wild takahē nests to boost the birds' recovery. Surplus eggs from wild nests are taken to the Burwood Breeding Centre.

An important management development has been the stringent control of deer in the Murchison Mountains and other takahē areas of Fiordland National Park. Following the introduction of deer hunting by helicopter, deer numbers have decreased dramatically and alpine vegetation is now recovering from years of heavy browsing. This improvement in its habitat has helped to increase takahē breeding success and survival. Current research aims to measure the impact of attacks by stoats and thus decide whether stoats are a significant problem requiring management.

One of the original long term goals was to establish a self-sustaining population of well over 500 takahē. The population stood at 263 at the beginning of 2013.

References[edit]

  1. ^ BirdLife International (2013). "Porphyrio hochstetteri". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013. 
  2. ^ Trewick, S.A. & Worthy, T.H. (2001) Origins and prehistoric ecology of takahe based on morphometric, molecular, and fossil data. In: Lee, W.G.; Jamieson, I.G. (ed.), The Takahe: 50 years of conservation management and research, pp. 31-48. Otago University Press, Dunedin, New Zealand.
  3. ^ UNEP-WCMC Species Page (April 2008)
  4. ^ Taylor, Barry, Rails: A Guide to the Rails, Crakes, Gallinules and Coots of the World. Yale University Press (1998), ISBN 978-0-300-07758-2.
  5. ^ del Hoyo, J. Elliott, A. & Sargatal, J. (editors). (1996) Handbook of the Birds of the World. Volume 3: Hoatzin to Auks. Lynx Edicions. ISBN 84-87334-20-2
  6. ^ BirdLife International 2009. Species factsheet: Porphyrio hochstetteri. Downloaded on 1 December 2009.
  7. ^ Williams, G.R. (1962) The Takahe (Notornis mantelli Owen 1848); a general survey. Trans. Royal Soc. New Zealand 88:235-258.
  8. ^ Mills, J.A. Lavers, R.B. & Lee, W.G. (1984) The Takahe: A relict of the Pleistocene grassland avifauna of New Zealand. New Zealand Journal of Ecology 7:57-70.
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