If you’re a penguin, your feathers are super-important: they keep you warm in chilly waters, they keep your skin dry, and provide you with a snappy tuxedo-like outfit.
But once a year, it all falls apart – literally. During a one-to two-week period each year, all of a penguin’s feathers fall out. This process is called molting, and it causes dramatic changes in the zoo’s African black-footed penguin flock.
“Each of our 17 penguins molts on a different schedule,” says zoo keeper Kasey DeLucenay. “There is almost always someone in the process.”
Molting begins with each penguin increasing its weight by about 50% in just a few weeks. “A bird that weighs five pounds might gain more than two pounds,” DeLucenay says. The weight gain helps a penguin get through the molt – a time when it can’t swim and hunt for fish – without eating.
During the molt, the penguins look scruffy, with patches of fluffy feathers popping up in random spots. “The molt seems to start at the tail and work its way up the body,” DeLucenay says.
Eventually, the old plumage is replaced by a sleek new set of feather. In juveniles, the brown feathers are replaced by the black-and-white plumage of the adults. As a finishing touch, the penguins preen each feather by rubbing it with waterproofing oil, which is taken from a gland at the base of the tail.
Click the photos below to enlarge.