The Southern Tokoeka on Stewart Island doesn't
mind being out during the day. But every other type
of kiwi is strictly nocturnal. Finding food is easier for the
kiwi after dark. Once the sun goes down, many
of the underground creepy crawlies it likes to eat move upwards
towards the surface of the soil.
Way-finding whiskers
The strange whiskers growing from the kiwi's forehead and the
base
of its beak are super-sensitive. These probably evolved to help
the
bird feel its way through the dark and would be of great benefit
to a
bird that mostly goes out at night.
A brilliant beak
The kiwi couldn't have evolved a more
perfect piece of hunting apparatus.
The kiwi is the only bird in the world
which has nostrils at the tip of its
beak! The kiw's beak is just like a
nose. To find food, it first uses its beak like a spear, probing
it into the
soil. Under the ground, the kiwi sniffs out a tasty critter, then
opens its
beak like a pair of chopsticks, clamps hard, and hauls its prey
from the
earth. If a kiwi catches an earthworm, it doesn't pull its prey
out of the
ground all in one go. Instead, the kiwi pulls in a series of smooth
movements, bit by bit. This is so that it doesn't break the worm
in half.
This adaptation has probably evolved over time
to enable to kiwi to make the best use of its
ground-living habits. Being able to sniff out its prey and then
pull it out of the ground easily, is one
feature which has evolved to give kiwi an advantage over other
birds.