Why Do Birds Molt?

For healthy feathers to grow, birds shed their old feathers, which is known as molting. This guide looks at the reasons that birds molt and how to care for them.

Aug 7, 2023By Lisa Szymanski
why do birds molt

Molting happens as birds naturally lose their old and torn feathers to grow new and healthy plumage. Feathers are important for flight and protection from predators and must be replaced as the older plumage becomes worn over time. Pet birds such as canaries, parrots, and budgies molt, too, and often require extra care to encourage the formation of new feathers. To understand why birds molt, we look at the reasons for feather loss, molting signs, and caring for pets when they lose their feathers.

What is the Purpose of a Molt?

baby penguin molting surrounded by adult penguins
A young penguin starts shedding its juvenile coat

Birds molt because they have to replace the older feathers that have been damaged or become brittle and worn with new ones. The loss of plumage during this period is only temporary, and stronger feathers will regrow. Depending on the season, feather loss helps birds cope in hot climates, while the growth of soft down keeps them insulated in winter. By replacing frayed feathers, birds can take flight quickly, helping them to evade predators.

The new plumage is essential for the survival of wild birds as it is both waterproof and windproof. For researchers and bird keepers, molting makes it easier to identify a bird’s age or life stage as its color changes when they mature. Juvenile penguins transform their fluffy down into waterproof black-and-white coats as adults, whereas goldfinches lose their colorful feathering in winter.

What Happens When Birds Molt?

blue jay molting
A blue jay with new feathers on its head

When birds start molting, they will lose their feathers, leaving them with thinned plumage or bare patches all over their bodies. The old feathering falls out and is replaced by full and healthy plumage over a few weeks. It is usually triggered by the onset of summer or winter, but the extent of the molt depends on the species and how old the animal is.

Typically, the tail, wing, and back feathers are shed, but it is not uncommon for birds to lose the feathers on their heads too. During this process, many birds experience changes in behavior. Fowl such as ducks and chickens become difficult to handle, while finches and cockatiels stop chirping. Replacing feathers consumes a great deal of energy, so birds are less active, and egg-laying is paused.

The Signs and Frequency of Molting in Birds

parakeet preening feathers while molting
A parakeet preening its feathers

The first sign that a bird is molting is the shedding of their feathers. You’ll notice thinned plumage where larger feathers fall out. These are replaced by pin feathers, which are tiny and sharp nubs that appear on the bird’s skin. They tend to preen more by picking the remaining plumage or using their heads to rub against their skin in an effort to relieve itchiness.

Pet birds are restless when handled, and previously active birds become quiet. The frequency of molting depends on the species, as parrots can molt up to three times a year, while budgies shed feathers once a year. The extent of a molt is also different for every bird. For example, budgies should never have bare spots while shedding, as it could be a sign of feather plucking instead of a normal molt.

How to Care for a Molting Bird: Diet and Grooming

cockatiel preening its feathers
Cockatiels grooming themselves

When your pet parrot, cockatiel, or canary starts molting, they need some extra care to grow healthy feathers and remain comfortable. Growing new feathers is an itchy process, so giving your pet bird a gentle rub or scratch can greatly relieve their discomfort. If they become restless while doing so, it is best to minimize handling until their pin feathers have fully developed.

The avian diet is crucial for a successful molt because it provides the vitamins and minerals needed to form new plumage. Each feather is made of keratin, which is a protein, so birds will require a protein-enriched diet to support new growth. Foods such as hard-boiled eggs, sunflower seeds, and mealworms are excellent protein sources. Be sure to protect pets that molt in winter from cold temperatures, as they lack insulation to keep themselves warm. Move them into an area that is free from drafts and moisture.

The Difference Between Molting and Feather Plucking

parrot feather loss on its back
Plucking can cause severe feather loss

During a molt, plumage is naturally shed, while plucking is the deliberate pulling and removal of feathers. When a bird plucks itself, it damages the plumage and follicles, leaving the skin exposed. Plucking can injure the developing pin feathers and increase the risk of infection and long-term feather loss. Many birds will over-preen themselves and may aggressively preen other birds in their enclosure. If you suspect that your avian companion is plucking their feathers, factors such as stress, isolation, or a diet low in calcium could be the cause. If your bird does not stop pulling their feathers, speak to your avian veterinarian about their condition.


swan flaps its wings on the lake
A swan displays its new feathers

Feathers are crucial for the health and protection of birds as they provide insulation, waterproofing, and assistance with flight. Healthy plumage must replace feathers that are no longer functional, and this is part of the reason why birds molt. Most birds, such as pigeons, ducks, swans, and eagles, experience molting at least once a year. One of the only species that does not molt is the ostrich, which does not fly and lives in a very warm climate. Molting is a fascinating process and nature’s way of ensuring that every flying creature is equipped to thrive in its habitat.

Lisa Szymanski
By Lisa Szymanski

Lisa is a wildlife enthusiast who enjoys hiking and gardening and has four years of experience volunteering at pet shelters. She is the proud mom of two dogs, a Pitbull named Ragnar, a Boerboel named Blueberry, and four feisty chickens, or as she calls them, the "queens of the yard," Goldie, Gray, Peaches, and Brownie.