Southern Brown Kiwi

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).

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.

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).

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).

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).

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

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).