Emperor penguins with chicks
When the chicks are larger and able to maintain their own body temperature, both parents are then able to leave them alone to go and fish for food to feed themselves and the growing chick. If it gets cold then the chicks then huddle together in "creches" for warmth and protection. while both parents are able to go off to collect food at the same time to provide for the ever increasing needs of the growing chick.
Chick survival has a lot to do with how the ice breaks up and so how easy it is for parents to reach the sea. If the parents have to travel long distances, many chicks will die of starvation. If the ice edge remains close, then the parents will be able to provide more food and the chicks stand a better chance of survival.
The colonies begin to disperse as the sea ice begins to break up in December and January, the chicks are then able to fend for themselves leaving the adults to moult their feathers ( a time when they stay out of the water) and so are not able to feed.
This picture by Jerome Maison. Ã‚Â© 2005 Bonne Pioche Productions
/ Alliance De Production Cinematographique.
From the Warner Brothers film The March of the Penguins used here by permission of Warner Brothers.