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Why Birds Molt
October 05, 2015

Don't you love those God moments?

When your breath is taken away, or when you are left speechless.

Mesmerised by something grand, or very simple.

A wow moment.

Wow moments are all around us, if we choose to look.

It is the ones that seem to jump at us that we seem to embrace.

A mountain scene, or a view from a valley.

Sunsets and a Great Lake or Ocean.

Starlit nights, or the Aurora Borealis.

Instead of the obvious wows of whale watching (I never have), it might be a school of minnows in a shimmering crystal clear lake.

As I showed last week, the intricate details of a spiderweb.

That can be a wow moment.

A just because touch from a loved one that gets you weak kneed right then and there.

Hummingbirds have been gone for several days when on back to back days (this past Friday and Saturday) late season hummers came calling.

It isn't often we have early October hummers, but not totally impossible either.

There are still plenty of flowers to nectar on.

Feeders are still up, but the birds preferred natural food.

It was no big deal, it simply caught my eyes and the right frame of mind.

Where I could say "How neat, thank you Lord".

Notice how one hummer has a little white spot on the crown of it head.

The real tubby one is a totally different bird, on a different day.

Fall bloomers (pictured throughout) add color and food for pollinators.

Also, the Red Salvia is at its best this time of year.

In this picture, late season (early October) goldfinch fledglings busily calling for and flapping their wings for mom to feed them.

American Goldfinches nest late, but still can have two broods.

I so enjoy the sights and sounds of late season fledglings.

Fledged cardinals in autumn are common for me as well.

It has been several years since I touched on this topic.

Birds Molting that is.

More goes into the process than I can write in a newsletter, however you may get the general idea.

Especially if you are new to caring for birds and wildlife gardening.


(Chocolate Eupatorium)

Birds must spend a great deal of time caring for their feathers, since their lives depend on them.

Preening, bathing, dusting, anting, and other feather care operations, cannot prevent the feathers from wearing out.

Because formed feathers (like our fingernails and hair) are lifeless, horny structures, incapable of being repaired, worn feathers must be replaced.

Also like our fingernails and hair, feathers are made of 'Keratin'.

This process of replacement is termed moulting, or molting.

The old, worn feathers are loosened in their follicles (sockets) by the growth of new intruding feathers, which eventually push them out.

Molting occurs in regular patterns over a bird's body.

The adaptiveness of such patterns can be illustrated by the arboreal woodpeckers, which retain the key inner pair of long tail feathers used in bracing and climbing until the outer feathers have been replaced.

This is the reverse of the pattern found in most birds, which molt tail feathers from the center of the tail first, and then progressively toward each side.

The majority of adult birds molt once or twice a year, and the temporal pattern, not unexpectedly, is related to the wear rate on the feathers.

Feathers of species that migrate enormous distances or live in thick brush, dodging among twigs and spines, wear more rapidly than those of birds resident in one place or live in open country.

The former tend to molt twice a year, and the latter only once.

(Purple Asters)

Molting is timed to meet various needs.

For example, resident temperate-zone birds require more insulating feathers in the winter than in the summer.

The number is changed in the process of molting; winter plumage may contain more than half again as many feathers as summer plumage.

Since the feathers, which carry the colors of birds, are "dead," a bird cannot totally change its colors without changing its feathers (although its appearance can change substantially just from wear).

Bright red cardinals have lost their sheen by late summer.

The white colors of other birds are worn down and appear a bit yellowed.

Therefore a male bird usually molts into his most colorful plumage prior to the breeding season.

Molting in most passerines takes from 5 to 12 weeks, but some raptors may require two years or more to completely replace their feathers.

Some birds, such as ducks, swans, grebes, pelicans, and auks, are "synchronous molters -- they change their feathers all at once in a period as short as two weeks, but sometimes stretching over a month.

During this period, they cannot fly, and males, in particular, often complete the process on secluded lakes in order to minimize their vulnerability to predators.


Molting is the process of a bird shedding old, worn feathers to replace them with fresh plumage.

A molt may be partial and replace just some of a bird's feathers, or complete when all the feathers are replaced at once.

The time it takes to complete a molt varies for different species, but may last as little as two weeks or as long as several years.

Some birds molt only once per year, while others may molt several times.

Why Molting Matters

Feathers are composed of keratin, the same protein that makes hair and fingernails, and they are under constant stress and subject to a great deal of damage.

Daily activities such as rubbing against bushes or trees, in and out of nest boxes or tree cavities.

Preening, bathing, anting, and dust bathing all subject feathers to friction that causes wear, and the keratin weakens as the feathers age.

Unlike your hair and fingernails that continually regenerate and grow, a feather is a complete structure and no longer grows once it reaches full size.

Feathers can't be trimmed or have the split ends cut off.

As damage accumulates, the feather's aerodynamic and insulating properties are compromised, and the feather must be shed so a new one can take its place.

How Birds Molt:

The exact cycle, frequency and timing of molt cycles varies for different species, yet every bird shares some similarities when molting.

In general, feathers are molted in a symmetrical pattern across the bird's wings, tail and body so it retains balance for flight. The entire cycle usually takes 5 to 12 weeks,

(Ducks often molt in as little as
two weeks, with a brief flightless period during the accelerated molting.)

Raptors, pelicans and parrots have some of the longest molt cycles and may take up to two years to replace all their feathers.

As feathers age, the quills loosen in their shafts and it is not until they are ready to fall out that new feathers begin to grow.

The new feathers, then, create visible gaps in a bird's plumage, particularly in the wings and tail, where shorter feathers are more noticeable.

On the body, nearby feathers overlap the bare space so the bird's skin is not exposed, but the bird may look scruffy and its markings will be indistinct until the molt is complete.

Goldfinches can appear as a quilted patchwork.

Molting requires a tremendous amount of energy, and birds do not molt during the breeding season and most don't molt during migration periods when that energy is needed for nesting or traveling.

The most common molting period is just after the breeding season, when food sources are still abundant but chicks are no longer so demanding, and birds can focus their energy on refreshing their plumage just before migration.

The second most common period is just before the breeding season, when food sources are increasing but there are not yet any chicks to care for, and this is the time when many birds develop their attractive breeding plumage.

The Dangers of Molting:

Molting can be a dangerous period for birds if there are not sufficient resources for them to molt properly.

Flying may be difficult if not impossible while molting, which makes birds more susceptible to predators, and while feathers are missing, a bird's insulation and protection from poor weather is compromised.

If a bird does not get proper nutrition while molting, its feathers may be thinner or poorly formed, creating difficulties that can last for months or years.

You can help ease the dangers of molting by providing a rich, reliable food source for birds to take advantage of, along with safe, secure shelter for birds that become more elusive and shy while molting.

Plant plenty of native trees, shrubs and berries that offer nutrient rich food and harbor protein rich insects.

If birds trust their habitat to meet their molting needs, they will stay around during this uncertain period, giving birders the opportunity to witness molting firsthand and enjoy ever more intimate knowledge of their favorite feathered friends.

Well, it is time to fly for now.

Before I go, here is your positive thought for the week.

God Bless.

“We can never have enough of nature. We must be refreshed by the sight of inexhaustible vigor, vast and titanic features, the sea-coast with its wrecks, the wilderness with its living and its decaying trees, the thunder-cloud, and the rain.”

Henry David Thoreau

Now from the word of God.

For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse.

Romans 1:20

"Treat the earth well:

It was not given to you by your parents,

It was loaned to you by your children.

We do not inherit the Earth from our

Ancestors, we borrow it from our Children."

Ancient Indian Proverb

Your friend indeed,

Ron Patterson

PS. If you enjoy these letters, please forward them to friends, family and co-workers.

Better yet, have them sign up so they can receive their own letters.

Gardening For Wildlife.

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