North Island brown kiwi

The genome of Apteryx mantelli was sequenced in 2015.[7]

Brown kiwi chick

Until 2000, the brown kiwi (then Apteryx australis) was thought to include the rowi and the tokoeka, in addition to the North Island brown kiwi. However using genetic codes from each of the above it was determined that the tokoeka was a separate species, it took the Apteryx australis name, leaving the brown kiwi with its current Apteryx mantelli name. Soon after, in 1998, more genetic tests were done with the rowi and it was determined that it (the rowi) was a separate species (Apteryx rowi). In 2004 an injured bird was found with streaked white around the head and identified by Massey University.[8] The white feathering is likely due to a rarely seen genetic variation sometimes described as a partial albino. Few documented cases exist with only a painting of one found in Ōtorohanga in the 18th century and a specimen in the Canterbury Museum. The injured bird recovered and was introduced into a breeding programme.

The brown kiwi was first described as Apteryx australis by Abraham Dee Bartlett, in 1813, based on a specimen from Dusky Sound, South Island, New Zealand.[9] This is a monotypic species.[10]

Brown kiwi are found in a number of parts of the North Island, including Northland, Coromandel Peninsula, the eastern North Island, Aroha Island, Little Barrier Island, Kawau Island, Ponui Island, and the Whanganui Region. The North Island brown kiwi has demonstrated a remarkable resilience: it has adapted to live on scrub-like farm land, exotic pine plantations, and native forests, but it prefers dense sub-tropical and temperate forest.[12]

A rare white Apteryx mantelli

Females stand about 40 cm (16 in) high and weigh about 2.8 kg (6.2 lb) the males about 2.2 kg (4.9 lb). The plumage is streaky red-brown and spiky. The North Island brown kiwi is the only species of kiwi found internationally in zoos.

These kiwi, like all kiwi, feed on invertebrates. They have 2-3 clutches a year with 2 eggs in each clutch. Chicks are fully feathered at hatching and are precocial, being able to leave the nest and fend for themselves within a week.[12]

The North Island brown kiwi is Vulnerable, per the IUCN Red List,[1] with the major threat coming from predators, such as dogs, cats, and stoat (Mustela erminea). 94% of chicks die before breeding in areas where mammalian pest control is not carried out.[12] It has an occurrence range of 38,400 km² (14,800 sq mi), with a population, estimated in 2000, of 35,000.[2]

In 1996 there were around 35,000 North Island Brown Kiwis and in 2006 there were 20,000.[13]

Nationwide studies show that on average only 5 percent of kiwi chicks survive to adulthood. However, in areas under active pest management, survival rates for North Island brown kiwi can be far higher. For example, prior to a joint 1080 poison operation undertaken by DOC and the Animal Health Board in Tongariro Forest in 2006, 32 kiwi chicks were radio-tagged. 57% of the radio-tagged chicks survived to adulthood. Thanks to ongoing pest control, the adult kiwi population at Tongariro has almost doubled since 1998.

In 2022, 11 North Island Brown Kiwi were released on Wellington's South Coast after a 100 year absence.[14] Fifty more kiwi were released into the hills of Wellington in May 2023.[15]

• Davies, S.J.J.F. (2003). "Kiwis". In Hutchins, Michael (ed.). Grzimek's Animal Life Encyclopedia. Vol. 8 Birds I Tinamous and Ratites to Hoatzins (2nd ed.). Farmington Hills, MI: Gale Group. pp. 89–92. ISBN 978-0-7876-5784-0.

Wikimedia Commons has media related to Apteryx mantelli.

• ARKive - images and movies of the North Island Brown Kiwi (Apteryx mantelli)
• Save the Kiwi (2008). "Population status of the North Island Brown Kiwi". Save the Kiwi. Archived from the original on 26 May 2009. Retrieved 9 July 2009.
• BirdLife Species Factsheet
• Video of North Island Brown Kiwi feeding in full daylight
• Taranaki Kiwi Trust