The North Island brown kiwi (Apteryx mantelli; Apteryx australis or Apteryx bulleri as before 2000, still used in some sources), is a species of kiwi that is widespread in the northern two-thirds of the North Island of New Zealand and, with about 35,000 remaining, is the most common kiwi. This bird holds the world record for laying the largest eggs relative to its body size.
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. 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 Otorohanga 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. This is a monotypic species.
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.
