Little spotted kiwi

The little spotted kiwi is a ratite and belongs to the Apterygiformes order, and the Apterygidae family. The genus name Apteryx means 'without wings' and the species is named owenii after Sir Richard Owen.^[6] Only the nominate subspecies A. o. owenii survives.

The little spotted kiwi was first described in 1847 by John Gould from a specimen obtained by Frederick Strange and sent to England.^[7] The locality is not recorded but it probably came from Nelson or Marlborough. In 1873, Henry Potts published an account of its habitats, and about this time specimens were collected in South Westland and sent to England.^[2] A specimen described as Apteryx occidentalis in 1893 is often considered a junior synonym of this species, but a study in 2002 indicated this may be a hybrid between Apteryx australis and Apteryx owenii.^[8]

There is a subspecies called Apteryx owenii iredalei, from the North Island, but its status as a subspecies is not universally accepted as valid.^[9] More commonly known as the North Island little spotted kiwi, it is an extinct subspecies of the little spotted kiwi that was native to the North Island, New Zealand.^[10] It was described by Gregory Mathews in 1935. Most subsequent authors do not recognise it or any other subspecies of Apteryx owenii.^[11] The North Island little spotted kiwi went extinct sometime in the late 19th century^[10][12] for unknown reasons; most likely from introduced invasive species such as stoats, feral cats, and other related species, or from human activity in the region. Two specimens were collected in the 1880s, being the only known remnants left.^[13]

The little spotted kiwi has a length of 35 to 45 cm (14–18 in) and the weight of the male is 0.88 to 1.36 kg (1 lb 15 oz – 3 lb 0 oz) and the female weighs 1 to 1.95 kg (2+1⁄4–4+1⁄4 lb), making it the smallest species of kiwi.^[9] Their feathers are pale-mottled grey, with fine white mottling, and are shaggy looking.^{[14][full citation needed]} They lack aftershafts and barbules. They have large vibrissae feathers around the gape. They lack a tail, but have a small pygostyle.^[2] Their bill is ivory-coloured and long and their legs are pale.^[14] Albinism in this species has been recorded.^[15]

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  Illustration by J. G. Keulemans from a work by G. D. Rowley, 1870s
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  Burrow entrance, Zealandia

The little spotted kiwi had an obligate louse that parasitised on it, Rallicola pilgrimi. In an example of conservation-induced extinction, all lice were killed when the kiwi were translocated to Kapiti Island.^[16][17]

This species is long-lived with a mean life expectancy of 45 years.^[15]

Studies on Kapiti Island show that they prefer flax, seral, and older forest habitats. Lower numbers are found in rough grassland and scrub, indicating that either they prefer other habitats or they simply need a larger territory to support themselves in these areas.^[14]

Little spotted kiwis eat grubs and other small insects that are found underground, and occasionally eat berries. Earthworms, cockchafer beetle larvae, caterpillars, cranefly larvae, and spiders are their most common foods,^[18] with annelids making up the largest percentage of the bird's diet;^[18] fruit of the hinau tree is also commonly consumed.^[18]

As they cannot fly and their eyesight is very poor, they depend on a keen sense of smell, long beak and talons for finding food. The birds use their sharp talons and long beak to dig into the ground and then probe its long beak through the softened ground.^[2]

Little spotted kiwi are nocturnal, and will call occasionally each night to advertise its territory and maintain contact with partners; often pairs will duet. They are very territorial, and fight conspecifics with their sharp claws, resulting in many feathers on the ground.

Reproduction

They nest in an excavated burrow, dug by both birds and sometimes lined with plant material. Eggs are laid from July to January. The clutch size is one to two eggs (15% have 2), which are incubated by the male for 63–76 days. Chicks stay in the nest for 2–3 weeks after hatching and require feeding for 4 weeks.^[2] The eggs, like in all kiwis, are very large for body size; representing around 25% of the female's body weight, being 10.5–11.3 cm (4.1–4.4 in) in length and 6.8–7.6 cm (2.7–3.0 in), with an average mass of 301 grams. ^[15]

At the time it was described (in the 1840s), the species was common on the western side of the South Island and in Marlborough. A regular trade in skins sprang up and large numbers were collected for European museums. Further, with the advance of European settlement, birds were killed by prospectors and others for food, and their attendant dogs and cats took their toll.^{[citation needed]}

The species was extinct on the North Island by 1938 when the last four South Island birds were moved from d'Urville Island to the population that had been established on Kapiti Island.^[9] After they were released on Kapiti Island, they were also moved to Red Mercury Island, Hen Island, Tiritiri Matangi Island, Chalky Island, and Long Island in the Queen Charlotte Sound.^{[citation needed]}

In 2000, about 20 little spotted kiwis were released into Zealandia. This was the first time since the 19th century that little spotted kiwis could be found on the mainland of the North Island.^[14] In 2015, 20 kiwis were translocated from Kapiti Island to Anchor Island.^{[citation needed]}

As the smallest species of kiwi, they would be very vulnerable to the main kiwi predators like cats, dogs, and stoats, if not mostly restricted to several off-shore island reserves (mainly Kapiti Island) which are mostly free of introduced predators. The little spotted kiwi's conservation status is listed as "range restricted" by Save the Kiwi, with a growing population. Formerly classified as "vulnerable" by the IUCN,^[19] it was suspected to be more numerous than generally assumed. Following the evaluation of its population size, this was found to be correct, and it was consequently downlisted to "near threatened" status in 2008 as, although not rare, its small range puts it at risk. The lack of predators, apart from weka, is important to its increasing numbers. It has an occupancy range of 340 km² (130 sq mi), and a population of 1,500 mature individuals was estimated in 2022.^[1]

In May 2025, 40 birds (20 males and 20 females) were translocated from Kapiti Island to the Brook Waimārama Sanctuary in Nelson, the largest fenced sanctuary in the South Island. The last known population to have lived in the region disappeared nearly a century prior.^[20]

In July, two little spotted kiwi were rediscovered on the mainland (outside of a fenced sanctuary) for the first time since 1978, following a tip-off from a hunter.^[21] A female and male bird were found in the Adams Wilderness Area in the South Island's West Coast Region.^[22]

A translocation of little spotted kiwi from Kapiti Island to Ao-ata-te-pō / Cooper Island is planned to take in 2028, where a trapping program has been carried out by tourist company RealNZ since 2015.^[23]