Kiwi

The shy and retiring kiwi

The kiwi is the smallest flightless bird in the world. It is found only in the temperate forests of New Zealand.

Class: Aves (birds)
Order: Apterygiformes (kiwi-like flightless birds)
Family: Apterygidae (kiwis)

The native Maoris named it kiwi from its call: 'ki-wi kiwi'. The call of the female kiwi is hoarse compared to the shrill voice of the male..
There are 3 species of kiwis - the brown kiwi, the great spotted kiwi and the little spotted kiwi.

The kiwi has a stout body, about 35 cm to 55 cm long. It is approximately 38 cm tall - about the size of a chicken. It has no tail and the wings are very small. The kiwi has a small head with a long, curved beak with nostrils at its tip. The upper bill is bent over the end of the lower. The eyes are very small but the ear openings are large. Kiwis have a sharp sense of hearing which helps them detect danger.

The body is covered with shaggy, ruffled brown feathers which completely hide the wings. At the base of the bill are long hair-like feathers, standing out like whiskers. These help the kiwi to feel its way around.

Nocturnal birds
Kiwis are by nature shy and retiring and are hard to find because they hide during the day in burrows or under logs and become active at night. They call loudly and continuously, moving about the forest with their beaks to the ground like a snuffling dog, scratching at the undergrowth with their feet and digging into soft soil for food.

When defending itself, the kiwi uses its strong short legs and claws.

Flightless Birds.
© WWF

Why doesn't the Kiwi fly?
Where there are no predators, birds often become flightless. In New Zealand long ago, food was plentiful and there was no danger of attack from land mammals, so the birds became ground foragers. Their bodies became heavier and their wings became smaller, and gradually they lost their power of flight..

The dodo of Mauritius was also a flightless bird: when humans came to Mauritius they found it easy to kill dodos which were hunted to extinction. The kiwi almost met a similar fate because for many years, it was killed for food and its feathers were used to decorate cloaks. But it is now protected in New Zealand.

What do Kiwis eat?
Kiwis are omnivorous, that is they eat both plants and animals. They feed largely on worms, insects and their larvae, berries and other plant materials. They normally do not drink water.

Kiwis leave a distinct stamp on their feeding ground: a series of deep crater-like beakmarks in the soil. These show where the birds have been digging, using their beaks to enlarge an opening from which they finally pull their prey out.

Unlike most birds, the kiwi relies heavily on its sense of smell to track its prey.

Caring for the young
A female kiwi is larger than the male and dominates the male in the relationship. The kiwi builds its nest in a hollow log, or among the roots of large trees, or in burrows, lining it with twigs, grass and feathers.

The main kiwi breeding season runs from June through to March, when the kiwi's food supply is most plentiful.

About 2-3 weeks after mating the female lays 1 or 2 eggs. The eggs are enormous for such a small bird - about 450 gm each! That makes them about 1/7th of the bird's weight.

Both the male and female build the burrow but only the male incubates the eggs. He sits on them and keeps them warm till they hatch in about 75 to 80 days. During this period the male may stay with the eggs for as long as a week at a time.

Once the chicks hatch, they are not often fed for the first 2 weeks, relying on the nourishment of the rich yolk within their egg. Thereafter, they are able to pick up food with the help of the male. Kiwis grow very slowly and may take 5 to 6 years before they reach breeding age.

Kiwi facts

• After a first meeting during mating season (June to March), kiwi usually live as monogamous couples. The pair will meet in the nesting burrow every few days and call to each other at night. Some couples have been known to be together for as long as 20 years!
• Kiwi are big travellers, superbly adapted to their natural habitat, agile and quick-moving.  A bird can cover his or her territory - possibly the size of 60 football fields - in a single night.
• A female kiwi can lay up to 100 eggs in her lifetime.