Kiwis - the National Bird of New Zealand
Ever wondered why people from New Zealand are sometimes called Kiwis? Have you ever seen a Kiwi, are you perhaps unsure of what a Kiwi even is? Is it a fruit? Is it a bird? Many visitors to New Zealand are unsure of the answers to these questions.
Hopefully this section of the Active New Zealand website will enlighten you a litte and maybe answer some of hose questions.
The Kiwi Bird
The most ancient of New Zealand’s birds, the kiwi evolved 70 million years ago from a flightless ancestor from the great southern continent of Gondwana. It’s a member of the ratite group, and related to the ostrich, emu and rhea as well as the now extinct New Zealand moa.This bird, even if it is not very often seen, is well known. It has given its name to New Zealanders, who are called "Kiwis" the world over. Yet all this time the bird has been a relatively secretive, nocturnal species seldom seen in the wild state.
Kiwis are relatively long - lived birds. Branding studies have not been going long enough to give a good indication of life expectancy, but 20 - 30 years is probable. Several brown and little spotted kiwis have lived in captivity for 20 years or more and one North Island brown is approaching 40.
There are two species of Kiwis in New Zealand. Brown Kiwis are found in forested areas in the North Island, Fiordland, South Westland and Stewart Island. Spotted Kiwis are found on offshore islands and forests in the North of the South Island. There are six varieties of the kiwi; the Great Spotted, the Little Spotted, the North Island Brown, the Okarito Brown, the Stewart Island Brown and the The Haast Brown.
The Maori hunted the birds at night with the aid of dogs and torches. The skins and feathers were made up in to cloaks which were highly prized. The Maori believed that the kiwi was under special protection of the god Tane, and they called it Te manu a Tane - the bird that Tane hid. Its voice is shrill and from the call comes its Maori name kiwi. The male utters a repeated prolonged whistling call. The female call is shorter and hoarser. During feeding they emit snuffling sounds.
The bird is nocturnal, tail-less and flightless. They are the only known bird to have external nostrils at the base of their long beaks and their sense of smell is very finely tuned. It locates the insects, grubs and spiders it eats by sniffing among the leaves, moss and rotting wood on the forest floor leaving characteristic bore marks. They tap the ground with their beaks and scrape away forest litter with their feet searching for food by pushing their beak about 15 cm into the ground and probing for insects, worms and snails. They also eat the berries from some native trees. Sometimes they make a snuffling sound, as they expel air through their nostrils while they feed.
Kiwi are burrowers and often move to a new burrow each day. The little spotted kiwi and the brown kiwi tend to use simple one-entrance burrows, but the great spotted kiwi puts time and effort into constructing a labyrinth of tunnels. Kiwi live in pairs, as couples, all their lives. Male kiwi fight vigorously for a mate and the female occasionally kicks her smaller partner when warding off his unwanted advances. About every third day, the pair shelter together in the same burrow. During the night when they are foraging for food or patrolling their territory, they call to each other. The calls of the male and female are quite distinct: he utters prolonged shrill whistles, while she has a lower, hoarser cry.
Kiwi are very strong and often extremely bad tempered. Adult birds use their razor sharp claws to defend themselves. Extremely territorial, they protect their "patch", which can be as large as 40 hectares, by calling, or chasing the intruder and kicking it. When alarmed or feeling aggressive, kiwi make noises that range from a growl to a hiss, along with loud bill-snapping.
Kiwis have only remnants of wings, and like the moa to which they are related , lack a keel on the breastbone for attachment of flight muscles. Though kiwis have weak eyesight, long bristles around there mouths help them feel their way through the undergrowth at night.
The nest is a burrow or depression under tree roots or a hollow log. It lays a clutch of eggs of 1 or 2 very large off-white eggs laid at an interval of 10-30 days. The eggs are about 180mm long and 80mm in diameter - six times as large as would be normal for a bird of its weight and weighing about 20% of the female's body.. The incubation period is 72-80 days, usually by the male.
Throughout the incubation period the male covers the nest with sticks and leaves each night and goes off to search for food. Sometimes he also leaves it during the day. This makes the eggs vulnerable to predation by mammals and sometimes weka. For the first week after it hatches, the kiwi chick relies on the yolk sac from its egg for food. At one week old, it emerges from the nest for the first time. It looks just like a small adult kiwi. For more than two weeks the male and the chick share the burrow during the day, while at night both parents stay close enough to the chick to protect it.
The male kiwi leaves the nest when the chick is about three months old. Soon after, the chick leaves the nest and for the next few weeks, finds its own shelter during the day. The young kiwi feeds at night, keeping its distance from its parents, who seem to tolerate its presence less.
By the following spring the chick has moved out of the parents territory altogether. It moves around, staying in a variety of places where it may be chased out by other kiwi, until it finds an empty territory.
Even scientists in the know have difficulty the sex of Kiwis and staff at the Queenstown Kiwi and Birdlife Park were a tad surprised when "Baldric" hatched an egg. So the Massey University and a bit of DNA sampling are trying to improve on the traditional methods used - bill length, call and size. I think I would rather leave it a surprise ....
The Kiwi survived for so many million of years because its protective colouration and hidden lifestyle protected it from the old native enemies - threats from the air by the giant eagle Harpagornis or the huge harrier, both now extinct themselves. But the kiwi was in no way equipped to protect itself against the threats from the ground - stoats, ferrets, weasels, possums, pigs, dogs, cats and humans.
Resourceful it may be - strong, fleet-footed and feisty - but the kiwi has exhausted its own resources and is now dependent on ours.