Great spotted kiwi (Apteryx haastii)

KingdomAnimalia
PhylumChordata
ClassAves
OrderApterygiformes
FamilyApterygidae
GenusApteryx (1)
SizeMale size: 45 cm (2)
Female size: 50 cm (2)
Male weight: c. 2.4 kg (3)
Female weight: c. 3.3 kg (3)
Top facts

Classified as Vulnerable (VU) on the IUCN Red List 2006 (1).

The national symbol of New Zealand and its people, the kiwi is both a cultural icon and a biological oddity (4). The five kiwi species are unusual, pear-shaped, flightless birds (2) that have evolved in the absence of any native mammals and therefore developed features that help it occupy a mammalian niche, to the extent that the bird has been referred to as an ‘honorary mammal’ (4). The skin is tough and leathery, the feathers like hair and the rudimentary, indistinct wings end in a cat-like claw (2) (4). The kiwi is one of the few birds with a highly-developed sense of smell and the only bird in the world with external nostrils at the tip of its beak (2) (4). The large feet have fleshy footpads and mean that it can walk almost silently (4), and the long, slender bill is excellent for capturing insects and other prey (2). As its name suggests, the great spotted kiwi is New Zealand’s largest kiwi species (4), and has a light greyish-brown plumage mottled with white (5).

Confined to the South Island of New Zealand, where populations remain in three main, discrete areas: north-western Nelson to Buller River, Northern West Coast, and the Southern Alps between Arthur’s Pass and Lake Sumner (3) (4). A fourth population has also been established at Lake Rotoiti Mainland Island in Nelson Lakes National Park (4).

Found in a variety of habitats, including tussock grassland, damp, mossy beech forests, dry, alluvial podocarp and hardwood forest, and scrub-covered coastal pasture, from sea level up to 1,500 m, but mainly in the subalpine zone of 700 to 1,100 m (5).

Kiwis are strictly monogamous, usually pairing for at least two to three breeding seasons, sometimes for life (2). These birds are extremely territorial and, once mating pairs form, the nesting region is fiercely defended, usually by vocal displays but occasionally by physical battles (2) (4). Males are particularly aggressive towards intruders and are capable of inflicting fatal wounds with their powerful feet and legs, but serious injuries and death are rare and territories seldom change ‘ownership’ unless the resident male dies naturally or is crippled. Within these territories kiwis may have up to 100 different excavated burrows and usually use a different one each day for shelter (2). However, unlike other kiwi species, the great spotted kiwi prefers dens to simple burrows, constructing tunnels several metres long and with more than one exit (4).

Most breeding takes place in spring. The great spotted kiwi only produces one enormous egg per clutch, reaching up to 15% of the female’s body mass (4). The egg takes up so much space that the females cannot generally eat during the last few days before laying, so must accumulate a store of fat beforehand (2). The advantage is that this large, nutrient-rich egg produces fully-feathered young at an advanced stage of development, quickly able to take care of themselves (2) (5). The egg is incubated by both parents (4) for about 70 days, and within ten days of hatching the chick begins to hunt for food unaccompanied outside the nest, but returns to the nest each day for three to four weeks (5). The chick may feed during the day for the first six weeks of life, but then becomes exclusively nocturnal.

Kiwis set out on their hunt for food about 30 minutes after sunset, in search of insects, snails, spiders, earthworms, crayfish, fallen fruits and berries on which to feed (2) (5). Prey is found by the birds tapping the ground with their beaks and sniffing the earth, followed by plunging their beaks deep into the soil, stabbing back and forth to catch underground quarry (2).

The introduction of mammalian predators to New Zealand is the primary cause of decline of the kiwi, and has now placed New Zealand’s national icon in grave danger (2) (4). The drop in numbers of great spotted kiwis is due to habitat loss, predation of chicks and juveniles by mustelids (Mustela spp.), particularly stoats, nest predation by the brush-tailed possum (Trichosurus vulpecula), and predation of adults by dogs; all non-indigenous animals were introduced to New Zealand by European settlers near the turn of the 20th century (2) (5).

Awareness and concern for kiwi welfare has grown in recent years and, in 1991, the Kiwi Recovery Programme was launched, through which strategies such as predator control have benefited this and other kiwi species (2) (5). These unusual birds are also intensively monitored using call-counts, specially-trained dogs searching for banded birds, and radio-tracking (5). No other animal has been so linked to a country’s cultural identity as the kiwi bird, and with continued efforts by dedicated conservationists, the kiwi should hopefully remain a celebrated icon of New Zealand for many years to come (2).

For more information on kiwis see:

 

 

For more information on this and other bird species please see:

Authenticated (27/11/2006) by Dr. Hugh Robertson, Kiwi Co-ordinator (Research and Monitoring), Department of Conservation; and member of Bank of New Zealand Save the Kiwi.
http://www.savethekiwi.org.nz/

  1. IUCN Red List (September, 2006)
    http://www.iucnredlist.org
  2. Animal Diversity Web (October, 2006)
    http://animaldiversity.ummz.umich.edu/site/accounts/information/Apteryx_haastii.html
  3. New Zealand Birds (October, 2006)
    http://www.nzbirds.com/birds/kiwigs.html
  4. Bank of New Zealand Save the Kiwi (October, 2006)
    http://www.savethekiwi.org.nz/Home/
  5. BirdLife International (October, 2006)
    http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=10&m=0