Having evolved in an environment without any mammalian predators, kiwis have some distinctly mammal-like traits. For example, body temperature is 38 degrees Celsius, about 2 degrees Celsius lower than most birds (4), but within the normal range for many mammals (5). Kiwis also have an excellent sense of smell, one of the most developed among birds, aided by the unique placement of the nostrils at the end of the bill (5). Kiwis feed by jabbing the bill into the soil to search for insects and worms, this causes the nostrils to become clogged, and requires vigorous blowing and sneezing to clear them again (4). The tokoeka is highly territorial and has been known to attack humans when defending its territory (3). Unlike most other kiwis, which tend be more solitary, the tokoeka lives in family groups occupying a shared territory, the size of which depends on food abundance (4). Egg laying begins in July, continuing through to November in the Stewart Island populations and December in the South Island populations (5). A single egg is laid within a small burrow, and both parent birds and other birds within the family share incubation duties. This is a useful behaviour, since the incubation time is extremely long, usually between 70 and 80 days (4). During this time the males and females shed feathers from the breast, leaving a naked patch that is thought to help transfer heat to the egg during incubation. The chicks, which hatch fully fledged, leave the nest at one week old, but will remain in the family territory for up to seven years (5).

The tokoeka is one of five recognised species of kiwi, the iconic, flightless birds that are only found in New Zealand (3). This species is divided into two distinct, geographically separated races commonly known as the southern tokoeka and the Haast tokoeka. Both races have the distinctive kiwi features, a pear-shaped body that lacks a tail, and wings that are so reduced that they are barely noticeable. The plumage appears to be almost hair-like, a result of the loose structure of the feathers, which do not lock together as in other birds. Colouration varies between the two races, with the Haast tokoeka having reddish-brown plumage, while the southern tokoeka is grey-brown with black streaks. The kiwi's long, slender bill is unusual compared to other birds, in that it has nostrils at its tip. While both races of tokoeka have an ivory coloured bill, the southern tokoeka's bill is straight, whereas the bill of the Haast tokoeka, in contrast to all other kiwis, is markedly down-curved (4). In the wild, the tokoeka can be easily identified by its call, in the male this is a shrill ascending and descending whistle, while in the female it is lower-pitched and hoarse (2).

Apteryx australis is restricted to Fiordland and Stewart Island, with a tiny isolated population near Haast, New Zealand. In 1996, the total population was estimated at 27,000 (c.±25%) birds⁵. The species is common on Stewart Island (c.20,000 birds) and in localised areas in Fiordland (c.7,000 birds)^2,6. It is inferred that it could be declining on the mainland at a rate of 5.8% per year, like its congener A. mantelli, except perhaps in high-altitude habitats. It is stable on Stewart Island⁶.

Apteryx australis, commonly known as brown kiwis, is located in the Australian biogeographic region. They are endemic to New Zealand, and reside on North Island (in Northland and Taranaki), South island (in Fiordland and Westland), and Stewart Island.

Apteryx australis is considered by some authors to be made up of two, distinct species, corresponding to the previously recognized subspecies A. australis mantelli - now A. mantelli, and A. australis australis and A. australis lawryi - both retained within A. australis. North Island brown kiwis (A. mantelli) are the most common kind of kiwi, found only on the North Island of New Zealand. Apteryx australis includes populations on Stewart Island (A. a. lawryi) and South Island (A. a. australis), including populations in the Haast range and the fiordlands. Populations in the Haast range (Haast tokoekas) may represent a distinct species as well.

The population of brown kiwis found in Okarito forests on the western coast of the South Island was recently recognized as a distinct species, Apteryx rowi, Okarito brown kiwis or rowis. It is thought that this species is made up of only 200 individuals currently.

Biogeographic Regions: australian (Native )

Other Geographic Terms: island endemic

Endemic to New Zealand, the southern tokoeka's range is limited to Stewart Island and Fiordland on South Island. The Haast tokoeka has a small, isolated population near Haast on the west coast of South Island (2), and a colony of 50 birds has been introduced to Kapiti Island (4).

Brown kiwis are members of the flightless ratite group (Struthioniformes). They are unique in their small size and adaptations to forest floor life. These birds are roughly the size of a chicken, with the female being slightly larger. They range in size from 45 to 54 cm long, and weigh from 2.8 to 3.5 kg. They are brownish grey in color with long, soft feathers that look and feel very fur-like. Their skin is tough and they have whiskers at the base of their bill used for touch. This is especially important for these birds because they have small eyes and poor vision. These birds do not have a tail and their 5 cm long wings prevent them from flying.  Brown kiwis have powerful legs and can run quickly. The nostrils are at the end of their long bills and they have a keen sense of smell. The birds thrust their bill into the ground, gather the food, and beat the prey on the ground before they consume it. Other characteristics include heavy bone marrow, a body temperature lower than most other birds, and underdeveloped pectoral muscles. Brown kiwis have body temperatures of 38 degrees Celsius.

Range mass: 2.8 to 3.5 kg.

Range length: 45 to 54 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: sexes alike; female larger

Average basal metabolic rate: 4.029 W.

Habitat and Ecology

Systems

• Terrestrial

Brown kiwis live in subtropical and temperate forests and grasslands. They prefer to live in large, dark forest areas, which allow camouflage for the birds as they sleep during the day. In undisturbed habitats, kiwis create burrows under stones, banks of streams, or in soft flat open ground. In disturbed areas, these birds have had to adapt to human presence by establishing burrows in rough farmland under logs and shrubs.

Range elevation: 0 to 1,200 m.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: savanna or grassland ; forest ; scrub forest

Other Habitat Features: agricultural

The tokoeka occurs in a wide range of habitats, from coastal sand dunes to forest, tussock grassland and sub-alpine shrubs (2). It has even been found burrowing into snow for shelter on mountain slopes during the winter (4).

Brown kiwis are carnivorous, they feed mainly on soil and aquatic invertebrates such as worms, insects, crayfish, amphibians, and eels. They also eat fruit. At night, these birds use their long bills to dig deep into the ground to find creatures living on the ground. After they have caught something, they use their bills to beat the creature on the ground, or on stones to kill it before eating. Cone-shape holes left in the ground after hunting are easy ways to discover their occurrence in an area.

Animal Foods: amphibians; fish; insects; terrestrial non-insect arthropods; mollusks; terrestrial worms; aquatic crustaceans

Plant Foods: fruit

Primary Diet: carnivore (Insectivore , Eats non-insect arthropods, Vermivore)

Brown kiwis are important predators of invertebrates and may disperse seeds through their fruit eating.

Brown kiwis have many introduced predators, although they had few predators before dogs, pigs, cats, brush-tailed possums, and stoats were introduced to New Zealand. Dogs, pigs and cats tend to feed on adult birds. Stoats and cats feed on the young, and possums and stoats destroy kiwi eggs.

Known Predators:

• domestic dogs (Canis lupus familiaris)
• pigs (Sus scrofa)
• ferrets (Mustela putorius)
• stoats (Mustela erminea)
• domestic cats (Felis silvestris)
• brush-tailed possums (Trichosurus)

Anti-predator Adaptations: cryptic

Brown kiwis communicate through a cry, which sounds like a prolonged whistle slightly ascending and descending. Males make a mournful shriek, "kee-wee," and females have a low hoarse cry. Chicks tend to make a clicking sound. The cry indicates their presence at night, and helps in finding mates. They also congregate in companies from six to twelve. To hear the cry of brown kiwis, click here:   http://www.nzbirds.com/birds/sound/brownkiwi2.wav 

Kiwis are unusual among birds in having a keen sense of smell. They have an enlarged olfactory bulb.

Communication Channels: acoustic

The expected lifespan of brown kiwis after their first twelve months of their life is approximately 20 years in the wild. When in captivity, these birds usually live to be 30 years old, but some have lived up to 40 years.

Average lifespan

Status: wild: 20 years.

Range lifespan

Status: captivity: 40 (high) years.

Average lifespan

Status: wild: 20 years.

Average lifespan

Status: captivity: 30 years.

Average lifespan

Status: captivity: 35.0 years.

Maximum longevity: 35 years (captivity) Observations: In captivity, these animals have been reported to live up to 35 years (http://www.demogr.mpg.de/longevityrecords). There are also anecdotal claims that they can live up to 40 years in captivity.

Brown kiwis meet in nesting burrows every few days and call to each other at night to begin mating. This ritual occurs between March and June. The relationship is volatile and physical with the females primarily being the dominant one. They are monogamous unless a “better” mate comes along.

Mating System: monogamous

Brown kiwis breed throughout the year but only lay one egg at a time. A second egg might be laid four to six weeks after the first one. The eggs are unique because of their size relative to the adult bird's mass. Brown kiwi eggs are one-third of the female's mass, making them the largest eggs (relative to mass) of any bird. Incubation period lasts up to eleven weeks and the chicks are ready to leave the nest in approximately six to ten days. Females reach sexual maturity on average between the ages of three and five. Males reach this sexual maturity in approximately 18 months.

Breeding interval: Brown kiwis can reproduce as often as every 4 to 6 weeks. However, the massive energy investment that each female makes into any single egg means that she will not often lay eggs that frequently.

Breeding season: Brown kiwis breed throughout the year.

Range eggs per season: 1 to 1.

Average time to hatching: 11 weeks.

Range fledging age: 6 to 10 days.

Average age at sexual or reproductive maturity (female): 3- 5 years.

Average age at sexual or reproductive maturity (male): 18 months months.

Key Reproductive Features: year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate)

Average birth mass: 325 g.

Average time to hatching: 75 days.

Average eggs per season: 1.

Female brown kiwis dig out the nest and deposit the kiwi eggs, which are smooth and are either ivory or light green in color. After the eggs are laid, males take over incubation and nest maintenance until the eggs hatch. During this time males lose one-third of their weight. After hatching, the chicks do not rely on parents for food. They survive from the copious amount of yolk in their belly. Kiwi chicks venture out of the burrow soon after hatching, although there have been reports of chicks being near their parents for up to a year. Because kiwi chicks are slow, small (weighting only 275 grams and being five inches), and unable to respond to predators, few survive to twelve months old. After that time, they reach a size that enables them to escape most predators.

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

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 13
Species With Barcodes: 1

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2004
  Vulnerable
• 2000
  Vulnerable
• 1996
  Vulnerable
• 1994
  Not Recognized
• 1988
  Not Recognized

Brown kiwis are considered vulnerable by the IUCN. Currently, there are an estimated 27,000 brown kiwis. The primary threat to these birds is predation by introduced mammals. Populations seem to be declining.

US Migratory Bird Act: no special status

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: vulnerable

Classified as Vulnerable (VU) on the IUCN Red List (1).

Population Trend

Major Threats

The main threat to all kiwi species has been the introduction of mammalian predators to the environment, particularly stoats (Mustela erminea) and brush-tailed possums (Trichosurus vulpecula), which eat kiwi eggs, chicks and juveniles. Predation by domestic dogs and feral cats has also had a significant impact in some regions (2). As a direct result of predation by introduced species, the tokoeka populations on South Island have undergone dramatic decreases. In 1996 the total population of the Haast tokoeka, the rarest of all kiwi races, was estimated at just 225 individuals (5). In contrast, the southern tokoeka population on Stewart Island is currently the most abundant of all the kiwi species populations, due to the island being free from introduced stoats and weasels. As a result of the Stewart Island population's stability and abundance, the tokoeka's current status is classified as Vulnerable by the IUCN. However, this should not mask the fact that the South Island populations are much smaller and at far greater risk (2).

Conservation Actions

In 1991, having realised the plight of their national bird, the New Zealand Department of Conservation, sponsored by the Bank of New Zealand, launched the Kiwi Recovery Program. This ongoing project has involved various conservation strategies including predator control, the creation of kiwi sanctuaries, public outreach and education, as well as a captive breeding program known as Operation Nest Egg (6). Due to the very low abundance of the Haast tokoeka, one of the five kiwi sanctuaries, created in 2000, was chosen to be placed within the Haast tokoeka's range. While extensive efforts have been made in this region to trap stoats and thereby reduce predation, inhospitable climate and terrain have made this difficult (6). Other conservation strategies for the Haast tokoeka include the translocation of 50 individuals to Kapiti Island where predation is believed to be less intense (4). The Kiwi Recovery Program's goals for the period 2006 to 2016 are to continue with current strategies, to increase the public's awareness and involvement in kiwi conservation, and to work towards legislative measures to ensure that dogs are kept under control by their owners (6). These measures should hopefully ensure the survival and recovery of all species of kiwi.

There are no known adverse affects of brown kiwis on humans.

Initially hunted to make cloaks and for food, kiwis, including brown kiwis, are the national symbol of New Zealand. Much pride is taken by displaying the kiwi on things such as the national currency, sports uniforms, road signs and mascots.

Positive Impacts: body parts are source of valuable material; ecotourism ; research and education