When can we go swimming?

Emperor penguin chicks starting to fledge and get their adult feathers. The white patches on the chests of some of these penguins are of tight and water-proof adult feathers. Until these have grown all over, the chicks have to stay on land. Their juvenile down is great when dry, but pretty useless when wet.

This picture by Jérôme Maison. © 2005 Bonne Pioche Productions / Alliance De Production Cinématographique.
From the Warner Brothers film The March of the Penguins used here by permission of Warner Brothers.