All penguins
need to replace their feathers each year. Adults generally do this
after the breeding season. Once their chicks have moulted into their
own juvenile plumage the adults return to sea for a few days to build up
their own fat reserves and then come back ashore to moult. The moult
takes about three weeks and the birds can only stand around and fast.
This must be a partricularly miserable time for penguins. Because
they are moulting they lose their waterproof coats and cannot enter the
sea so they have to face the elements and starve until their smart new
set of feathers is ready.
Some penguins return to their home colonies to moult while others will
take up residence somewhere quite different. One example is this
King penguin who returns every year to Campbell Island for his moult.
This bird (the only King penguin on the Island) is an adult and probably
breeds on Macquarie Island about 1,000 miles away. But he prefers
the solitude and beauty of Campbell for his annual enforced moult.
Once penguins achieve their adult plumage, they do not change the pattern of it in any way during the moults. The pictures below of African Penguins were taken in successive seasons on Boulders Beach, so the birds must have moulted in between. Nevertheless, we were easily able to recognise the birds from the patterns of spots that had not changed in the slightest in the moults.
