Tokoeka
Encyclopedia
The Southern Brown Kiwi, Tokoeka, or Common kiwi, Apteryx australis, is a species of kiwi
from New Zealand
's South Island
. Until 2000 it was considered conspecific
with the North Island Brown Kiwi
, and still is by some authorities.
Apteryx australis is based on Greek and Latin. Apteryx means
"A-" without "pterux" wings, and "australis" from "auster" the south wind, and "-alis" relating to. Hence Relating to the south wind is the meaning of Australis, not Australia.
The Southern Brown Kiwi belongs to the Kiwi
family and it is a ratite
, and a member of the order Struthioniformes. Like all ratites, its sternum
has no keel, it is flightless, and it has a distinctive palate
.
The Southern Brown Kiwi is divided into two subspecies:
around its gape
, and it has no tail, only a pygostyle
. It has a length of 45 to 55 cm (17.7 to 21.7 in) and the female weighs 2.1 to 3.9 kg (4.6 to 8.6 lb) and the male weighs 1.6 to 2.8 kg (3.5 to 6.2 lb) Its bill is long and slender with a slight down-curve. Like other kiwis it is nocturnal. The color of its plumage is rufous with some streaking.
s, including earthworms, beetle larvae, snails, spiders, centipedes, and orthoptera
. Its gizzard
is weak, and underutilized due to the lack of plant matter. Its caeca are long and narrow and aid in digestion.
functions, allowing eggs from both ovaries to pass through. It is a monogamous species and once paired up, they will defend their territories with warning calls. The size of their territory is between 12 and 106 acre (4.9 and 42.9 ha). Nests are made in burrows, or sheltered beneath thick vegetation. The female lays 1-2 eggs, typically just 1, which the male incubates for 90 days. After a few days the chick will exit the nest and feed on its own, although it may stay around parents for a year. When not incubating eggs, they roost alone in sheltered places at ground level.
Southern Brown Kiwi live on the mainland (South Island
) and Stewart Island. On the South Island
, they live in Fiordland
and Westland
. Their range is temperate and sub-tropical forests, grassland, and shrubland, the denser the better,. They are widespread throughout Stewart Island where they also live on the sand dunes.
status group. They have an occurrence range of 9800 km² (3,783.8 sq mi) and population of 27,000, estimated in 1996. Brush-tailed possums, Trichosurus vulpecula, and stoats, Mustela erminea, will eat the eggs, while stoats and cats will eat chicks and juveniles. Adults are also under threat as dogs, ferret
s, and brush-tailed possum, attack them and the juveniles. The Stewart Island population is stable due to the lack of these predators, however stoats may have colonized the island in 2000.
Kiwi
Kiwi are flightless birds endemic to New Zealand, in the genus Apteryx and family Apterygidae.At around the size of a domestic chicken, kiwi are by far the smallest living ratites and lay the largest egg in relation to their body size of any species of bird in the world...
from New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
's South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
. Until 2000 it was considered conspecific
Conspecificity
Conspecificity is a concept in biology. Two or more individual organisms, populations, or taxa are conspecific if they belong to the same species....
with the North Island Brown Kiwi
North Island Brown Kiwi
The North Island Brown Kiwi, Apteryx mantelli, Apteryx australis or Apteryx bulleri before 2000 , is a species of kiwi that is widespread in the northern two-thirds of the North Island of New Zealand and, with about 35000 remaining, is the most common kiwi.-Taxonomy:Until 2000, the Brown Kiwi was...
, and still is by some authorities.
Taxonomy
"A-" without "pterux" wings, and "australis" from "auster" the south wind, and "-alis" relating to. Hence Relating to the south wind is the meaning of Australis, not Australia.
The Southern Brown Kiwi belongs to the Kiwi
Kiwi
Kiwi are flightless birds endemic to New Zealand, in the genus Apteryx and family Apterygidae.At around the size of a domestic chicken, kiwi are by far the smallest living ratites and lay the largest egg in relation to their body size of any species of bird in the world...
family and it is a ratite
Ratite
A ratite is any of a diverse group of large, flightless birds of Gondwanan origin, most of them now extinct. Unlike other flightless birds, the ratites have no keel on their sternum—hence the name from the Latin ratis...
, and a member of the order Struthioniformes. Like all ratites, its sternum
Sternum
The sternum or breastbone is a long flat bony plate shaped like a capital "T" located anteriorly to the heart in the center of the thorax...
has no keel, it is flightless, and it has a distinctive palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
.
The Southern Brown Kiwi is divided into two subspecies:
- A. a. australis, South Island Brown Kiwi , with a population of approximately 7,000 birds is found on the South Island of New Zealand. A disjunct population, called the Haast Brown Kiwi is rare (with only about 250 specimens left) and is characterised by its rufous plumage. The Haast Brown Kiwi is named for where it lives, HaastHaast, New ZealandHaast is an area in the Westland District territorial authority on the west coast of New Zealand's South Island. The Haast region covers over ....
. - A. a. lawryi, Stewart Island Brown Kiwi is relatively common (20,000 birds) throughout its range, with about 17 birds per square kilometre. Its feathers are streaked lengthwise with reddish-brown.
Description
It has no preen gland, and its feathers have no aftershafts and no barbules. There are large vibrissaeVibrissae
Vibrissae , or whiskers, are specialized hairs usually employed for tactile sensation. The term may also refer to the thick hairs found inside human nostrils, but these have no sensorial function and only operate as an airborne particulate barrier...
around its gape
Gape
In bird anatomy, the gape is the interior of the open mouth of a bird and the gape flange is the region where the two mandibles join together, at the base of the beak...
, and it has no tail, only a pygostyle
Pygostyle
Pygostyle refers to a number of the final few caudal vertebrae fused into a single ossification, supporting the tail feathers and musculature. In modern birds, the rectrices attach to these....
. It has a length of 45 to 55 cm (17.7 to 21.7 in) and the female weighs 2.1 to 3.9 kg (4.6 to 8.6 lb) and the male weighs 1.6 to 2.8 kg (3.5 to 6.2 lb) Its bill is long and slender with a slight down-curve. Like other kiwis it is nocturnal. The color of its plumage is rufous with some streaking.
Vocalization
Southern Brown Kiwi communicate vocally to aid in defending their territory. They will also sing duets with each other, with the female shrill "kee-wee" or "kee-kee" and the males hoarse " kurr kurr". Males are more vocal and they both call in an upright position with their legs stretched out and their bill pointing up.Diet
The Southern Brown Kiwi has a long slender beak with lateral nostrils at the tip, which helps give them their keen sense of smell. They utilize this, more than sight and sound, to forage in dirt for invertebrateInvertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s, including earthworms, beetle larvae, snails, spiders, centipedes, and orthoptera
Orthoptera
Orthoptera is an order of insects with paurometabolous or incomplete metamorphosis, including the grasshoppers, crickets and locusts.Many insects in this order produce sound by rubbing their wings against each other or their legs, the wings or legs containing rows of corrugated bumps...
. Its gizzard
Gizzard
The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ found in the digestive tract of some animals, including birds, reptiles, earthworms and some fish. This specialized stomach constructed of thick, muscular walls is used for grinding up food; often rocks are...
is weak, and underutilized due to the lack of plant matter. Its caeca are long and narrow and aid in digestion.
Reproduction
The Southern Brown Kiwi, like all kiwi, has two functioning ovaries, however only the left oviductOviduct
In non-mammalian vertebrates, the passageway from the ovaries to the outside of the body is known as the oviduct. The eggs travel along the oviduct. These eggs will either be fertilized by sperm to become a zygote, or will degenerate in the body...
functions, allowing eggs from both ovaries to pass through. It is a monogamous species and once paired up, they will defend their territories with warning calls. The size of their territory is between 12 and 106 acre (4.9 and 42.9 ha). Nests are made in burrows, or sheltered beneath thick vegetation. The female lays 1-2 eggs, typically just 1, which the male incubates for 90 days. After a few days the chick will exit the nest and feed on its own, although it may stay around parents for a year. When not incubating eggs, they roost alone in sheltered places at ground level.
Range and habitat
| Location | Population | Date | Trend |
|---|---|---|---|
| Stewart Island | 20,000 | 1996 | Stable |
| Fiordland Fiordland Fiordland is a geographic region of New Zealand that is situated on the south-western corner of the South Island, comprising the western-most third of Southland. Most of Fiordland is dominated by the steep sides of the snow-capped Southern Alps, deep lakes and its ocean-flooded, steep western valleys... |
7,000 | 1996 | |
| Haast Haast, New Zealand Haast is an area in the Westland District territorial authority on the west coast of New Zealand's South Island. The Haast region covers over .... |
300 | 2008 | Increasing |
| Total (New Zealand New Zealand New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga... ) |
27,000 | 1996 | Stable |
Southern Brown Kiwi live on the mainland (South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
) and Stewart Island. On the South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
, they live in Fiordland
Fiordland
Fiordland is a geographic region of New Zealand that is situated on the south-western corner of the South Island, comprising the western-most third of Southland. Most of Fiordland is dominated by the steep sides of the snow-capped Southern Alps, deep lakes and its ocean-flooded, steep western valleys...
and Westland
Westland District
Westland District is a territorial authority on the west coast of New Zealand's South Island. Its population is - Government :The Westland District is governed by an elected Council, headed by an elected Mayor. The Mayor is elected at large. The current Mayor is Maureen Pugh. Councillors are...
. Their range is temperate and sub-tropical forests, grassland, and shrubland, the denser the better,. They are widespread throughout Stewart Island where they also live on the sand dunes.
Conservation
In 2000, after being recognized by IUCN, they were placed in the VulnerableVulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
status group. They have an occurrence range of 9800 km² (3,783.8 sq mi) and population of 27,000, estimated in 1996. Brush-tailed possums, Trichosurus vulpecula, and stoats, Mustela erminea, will eat the eggs, while stoats and cats will eat chicks and juveniles. Adults are also under threat as dogs, ferret
Ferret
The ferret is a domesticated mammal of the type Mustela putorius furo. Ferrets are sexually dimorphic predators with males being substantially larger than females. They typically have brown, black, white, or mixed fur...
s, and brush-tailed possum, attack them and the juveniles. The Stewart Island population is stable due to the lack of these predators, however stoats may have colonized the island in 2000.