These are birds belonging to the order Apterygiformes which occurs only in New Zealand. With moas they are among our most ancient birds and have probably been present in New Zealand since before the end of the Cretaceous period, about 70 million years ago, after which time connections with large land masses beyond New Zealand ceased to exist. Both kiwis and moas are Ratite birds – possessing no keel on the breastbone, or sternum, and are unable to fly. No extinct species of kiwi is known. The three recent species are: the common kiwi, Apteryx australis, with three races, one each in North, South, and Stewart Islands; the little spotted kiwi, A. oweni, now found along the whole of the western side of the South Island; and the great spotted kiwi, A. haasti, which occurs from western Nelson to about mid-Westland.
Kiwis stand about a foot high and have a long tapering and flexible bill, longer in the female than in the male, with nostrils at its tip. Their feathers are loose, shaggy, and rather hairlike, and their colour is brown or greyish with dark streaks or spots. The plumage of the sexes is alike; there is no tail. Legs and toes are very powerful. The call of the male is a plaintive disyllabic shriek of kee-wee; that of the female, a lower hoarser cry. There are, however, minor differences between the calls of the various species and races. Nests are made in crevices or burrows, and the clutch is of one or two white eggs, each weighing about a pound. These are perhaps the largest eggs, proportionately, of any bird. Incubation is carried out mainly by the male and takes about 11 weeks. Kiwis are semi-nocturnal; they inhabit forest and semi-pastoral lands. Though commonly believed to be rare and verging on extinction, they are in fact still present in fair numbers in those large expanses of native forest still remaining, and they even show signs of adapting themselves to the fringes of farmed areas.
Food consists of worms, grubs, insects, and berries and it is assumed that in kiwis the sense of smell is important in finding food. In all other birds the olfactory sense is poorly developed.
by Gordon Roy Williams, B.SC.(HONS.)(SYDNEY), Lecturer in Agricultural Zoology, Lincoln Agricultural College.