Once a year, Little Penguins go through a catastrophic moult - a fitting name, as they lose all their feathers at the height of summer. Without their waterproof plumage, these seabirds can’t cool themselves down like they usually do by swimming. So, during their annual moult they are stuck on land, hungry, hot, and generally uncomfortable, sometimes with bellies so full they can barely stand upright! Adult penguins have to moult every year to replace any worn feathers and maintain their water-proofing. Moult is triggered by breeding hormones decreasing during the breeding cycle. The onset of the moult is variable but it coincides with the best time to avoid conflict with vital events in the annual life cycle.
Moulting takes place after chick rearing, generally over February and March, however little penguins have been found to enter the moult period as early as January and as late as June. As their feathers will no longer be able to perform their required function, the little penguin cannot enter the ocean until their new feathers have fully grown through. This is vital for a species that spends 80% of their time in the water, sometimes spending weeks on the ocean at a time during the Winter period. Little Penguins moult all of their roughly 10,000 feathers at the one time. For Little Penguins, this means spending a couple of weeks out at sea fattening up before coming ashore for approximately 17 days to moult. During this time they are not water-proof and must stay on land fasting, which means prior to moulting they can double their average weight. These are tough times in the life of Little Penguins but you can help by adopting one with our Penguin Foundation to support our research & vital conservation efforts. Find out more here and thanks for your support.