Adelie land reclaims the sea with every passing day and every drop in temperature.
Emperor penguins are on their own now.
Why did they wait for winter?
One egg, one hope in the most inhospitable place on earth.
There's a reason, the emperor's sheer size.
To growing the image of one's parents takes time.
So the emperor penguin chooses the longest season to raise his offspring.
A delicate transfer of responsibility , now takes place.
Males close ranks for the duration.
As for the females, they are now free to strike out across the ice for hunting grounds at sea.
Two hundred kilometers of ice lie ahead of them.
The outward journey takes a month.
New ice fields turn the quest for open water into an endless mirage.
Female emperors probably tap into magnetic forces to negotiate this wall of mirrors.
They navigate like all great explorers with the sun and the stars.
Inland winds pack speeds of 250 kilometers an hour.
Temperatures drop to minus 70 degrees Celsius.
The emperors continue to incubate in a tight but movable scrum.
They shift gently from inside to outside to keep warm.
Two months after giving up their eggs, mothers return with impressive punctuality.
The sight of fattened females reporting back for maternal duty warms the cockles in males hearts.
But family reunions will not last long.
Male emperors have lost a lot of weight, t hey desperately need to feed.
And so do the chicks if they're to survive the rest of the winter, which won't be easy.
They must stay close for comfort and safety , or die.
Those that survive have until summer to shake off their downy innocence and learn to fend for themselves.
Spring put some bounce into their lives.
Adult emperors still shadow the young pretenders , but within a few months, they've earned their independence.