Before a male kiwi can get a mate, he must first find his
own territory, which may lead to fighting another male
for space, if he cannot find vacant land. Kiwi are very
territorial birds. They fight to protect their land
(which can be as much as 100 hectares) by calling, and
will even attack other kiwi if they have to. Calling
fights often happen on the land between territories, with
kiwi speeding back into their own land before returning
their neighbour's call. Kiwi
sometimes kill each other fighting over land -
their sharp claws and strong legs and feet can inflict
Once bonded as a pair, a male and female kiwi usually
live all their lives together.
Their territory may be very large, up to 100 hectares
for a pair of Okarito Brown Kiwi or Haast Tokoeka.
The kiwi breeding season goes from June to March., these
months are when kiwis have a lot of food. Males can reach
sexual maturity at age 18 months in captivity, but in the
wild usually don't breed until much older. Females lay
their first eggs at 3-5 years of age.
Unlike most male birds, which are able to get a mate with
their colourful feathers, the male kiwi has drab brown
feathers, and so has developed some interesting ways to
try and get a female's attention.
The male follows the female about, grunting at her. If
she pays no attention, she may run away from him, or even
chase him away.
After mating the egg will
take three weeks to be laid
In kiwis, both ovaries are functional (unlike most other
birds where only the left ovary develops), and if more
than one egg is laid in a breeding season, ovulation
occurs alternately in each.
The female kiwi must consume three times as much food as
usual to produce her huge egg, which is one of the
largest, in ratios to her size, of any bird in the world.
This egg is six times the
size of a normal bird of her size would lay and contains
the largest proportion of yolk. The kiwi
egg has a smooth, thin, white or greenish-white shell and
is about 120mm long and 80mm in diameter .One would
expect the kiwi to have an egg about the size of a hen's,
but. the egg is about the same size as the moa's, which
makes people think that the kiwi was once a much bigger
The production of a large egg is a big effort for the
female kiwi. A pregnant female's belly expands so much
that it touches the ground. It
makes up 15-20 percent of her bodyweight.
A female will sometimes stand up to her belly in cold
water when she is heavy with egg, to help relieve her of
the weight she is carrying. Just before it is laid, the
egg is so huge it almost fills the kiwi's whole body,
leaving little room for food in her stomach. She cannot eat for 2 or 3 days
before the egg is laid.
The huge egg is laid quickly. The female
then leaves the burrow so that the male can take over the
hatching of the egg. If the female is to lay another egg,
it will have already begun developing inside her, and
will be laid nearly one month after the first one. It is
rare, but not unknown, for a third egg to be laid. The
North Island Brown Kiwi will often lay 2-3 eggs each
The male sits on the eggs
for two and a half months to hatch them.
This is a long time but it is because the egg is so big
and the Kiwis body temperature is lower than other birds,
so it takes a lot longer to hatch. The male
leaves the burrow to feed at night. In some types of
kiwi, both the male and female sit on the egg.
The Kiwi Chick
It takes up to three days for the Kiwi chick to break out
of the shell. When the egg hatches the chick can already
stand and walk. The yolk sack will feed it for a week.
Because the Kiwi chick is so big when it hatches the
chick only stays with the parents for 3 weeks before they
kick it out of the nesting burrow, if it trys to return
the parents use their powerful legs to litereally kick
the chick away.
Links to More
Kiwi recovery Organisation