Winter has taken its toll

and the males have lost half their body weight

They're also left holding the baby.

These newly hatched chicks can expect very little from their fathers.

After four months of fasting, there's nothing solid in a male's stomach,

but he is able to produce a protein-rich secretion.

but that is barely enough to keep a chick alive for a week.

Fattened up from two months fishing,

the females reappear with magically accurate timing.

In such a crowd, calling is the best way to locate a partner.

A female arrives to take over.

At first, the male is a little reluctant to abandon his offspring.

Once the exchange starts, it needs to be quick.

A few minutes on the ice would almost certainly kill the chick.

Now at last, the chick can feed properly.

During the next five months,

an emperor chick will eat 100 kilos of food.

In one big helping it can eat a third of its own bodyweight.

Now at last their fathers have a chance to eat,

but the ice edge may be several hundred kilometres away.

Emperor penguins have a faster mode of transport than just plain walking.

They can toboggan.

From now on males and females will take turns to go fishing.

Each trip may involve travelling thousands of kilometres, in search of food.