What does it mean when birds molt?
When I was very young, I used to think that when birds molted their feathers it meant they dropped every feather at once and were running about looking like a plucked chicken. Thankfully, I quickly figured out that this was not the case. Feather molting in birds is a complicated process that can vary between individuals, species and years. Molting serves two purposes: to replace worn or damaged feathers, and to provide different plumage that helps indicate a bird’s age, sex, and season of the year, as many birds have differing winter and summer plumages. Most birds will molt once or twice a year, and each molt is classified as a partial molt or complete molt. Partial molt means that only some of the feathers are replaced in that cycle, and the others will be replaced in the next cycle that year or the following year. Complete molt means that every feather is replaced at some point during one cycle.
Now, even though birds do not drop every single feather they have at once, molting still can make it difficult and even impossible for some birds to fly. Most ducks and geese will molt their primary flight feathers at one time, which leaves them grounded until new feathers are grown within a few weeks. During this flightless period, the sitting ducks stick close to ponds and lakes which provide them with an easy escape from predators who won’t follow a bird into deep water. Other birds, who may have limited flight ability as well, will stay in dense shrubs and woods to hide from potential predators. This secretive behavior makes it difficult to see birds molting in the wild, but you can often witness molting firsthand here at Zoo Atlanta. Many of our colorful birds, such as the golden pheasant, molt yearly to replace their vibrant beautiful plumage each season. So next time you’re at Zoo Atlanta and see a bird that is looking a bit ruffled and bare, just remember, they may be molting and will soon be a fully feathered beauty once more!
**It is illegal to collect feathers from native migratory species due to the Migratory Bird Treaty Act. For more info visit https://www.fws.gov/lab/featheratlas/featherlaw.html **
Keeper I, Birds