Porphyrio hochstetterisouthern takahe

Last updated:

Geographic Range

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. (Wallace, 2002)

Habitat

Mainland populations can be found in alpine tussocks grasslands and sub-alpine shrublands. Island populations live in modified grasslands. (Benstead, et al., 2007)

Physical Description

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. (Benstead, et al., 2007; Benstead, et al., 2007)

  • Sexual Dimorphism
  • sexes alike
  • male larger
  • Average mass
    Male 2.7 Female 2.3 kg
    lb
  • Average length
    63 cm
    24.80 in

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. (Ryan, 1997)

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. (Ryan, 1997)

  • 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

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. (Ryan, 1997)

  • 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

Lifespan/Longevity

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. ("Kiwi Conservation Club", 2005)

  • Range lifespan
    Status: captivity
    20 (high) years

Behavior

South Island takahe are highly territorial, most confrontations occur during incubation. They are active during the day. (Ryan, 1997)

Home Range

Home ranges of South Island takahe vary in size from 1.2 to 4.9 ha., densities are highest in moist lowland habitats. (Ryan, 1997)

Communication and Perception

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

Food Habits

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. ("Kiwi Conservation Club", 2005)

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • roots and tubers
  • seeds, grains, and nuts

Predation

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. (Baber and Craig, 2003; Jamieson and Ryan, 2000)

Ecosystem Roles

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

Economic Importance for Humans: Positive

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

Economic Importance for Humans: Negative

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

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. (Baillie and Groombridge, 2007; Wallace, 2002)

Other Comments

South Island takahe was formerly recognized as Porphyrio mantelli. It was later split into P. mantelli (extinct) and P. hochstetteri. This species is also commonly called "southern takahe." The extinct close relative, P. mantelli is also known as "North Island takahe." (Baillie and Groombridge, 2007)

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Jose Lara (author), Northern Michigan University, Alec R. Lindsay (editor, instructor), Northern Michigan University.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

folivore

an animal that mainly eats leaves.

herbivore

An animal that eats mainly plants or parts of plants.

island endemic

animals that live only on an island or set of islands.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

2005. "Kiwi Conservation Club" (On-line). The Takahe. Accessed April 12, 2008 at http://www.kcc.org.nz/birds/takahe.asp.

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.

Baillie, J., B. Groombridge. 2007. "Porphyrio hochstetteri" (On-line). IUCN Red List of Threatened Species. Accessed April 02, 2008 at http://www.iucnredlist.org/search/details.php/40130/summ.

Benstead, P., R. McClellan, J. Pilgrim. 2007. "Species factsheet: Porphyrio hochstetteri " (On-line). BirdLife International. Accessed April 18, 2008 at http://www.birdlife.org/datazone/species/?action=SpcHTMDetails.asp&sid=2929&m=0.

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.

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.

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