Plumage and Coloring

Overview of Plumage and Coloring as Communication

Plumage is usually the first thing that we notice about a bird, using its colorings and markings to help with the positive and accurate identification of different species.

But the colors and patterns of a bird’s feathers are not only useful to birdwatchers. They also help birds themselves to communicate with each other, to convey messages of courtship and warning, and to signal status to potential mates.

The Vivid World of Bird Plumage

Every color of the rainbow features on the plumage of bird species around the world, from lurid Green Parakeets to the deep violet Hyacinth Macaw, hot pink Flamingos, and the shimmering rusty orange of Rufous Hummingbirds.

As well as helping humans to distinguish between species and record accurate observations, plumage serves multiple purposes for birds themselves, including camouflage, mating and sexual selection, communication, and territorial defense.

Ahead of the breeding season, male plumage is at its most vibrant and impressive, and elaborate, colorful displays are often used to attract a female mate.

The brightest feathers are associated with strong, dominant males, advertising their prime health and genetics. Colorful feathers are also used to assert a claim to a territory or indicate dominance against any challengers.

Pictured: A Rufous Hummingbird. Plumage serves multiple purposes for birds themselves, including camouflage, mating and sexual selection

Understanding Bird Plumage

Baby birds, covered in down or barely covered at all, look completely different from the fully grown, fully feathered adult birds we see foraging in our backyards or soaring through the skies. Juvenile herring gulls, for example, take up to four years to develop the plumage of a mature bird.

Not only do the coloring and patterns of feathers help humans distinguish between species and ages of birds, but they also convey important messages about the health and genetic status of other birds of the same species.

Types of Plumage

When a bird hatches, its appearance is usually considerably different from how it looks as an adult. Birds undergo various molts during their lifetime, through their juvenile stage, when they reach maturity, and often on an annual basis to ensure their feathers remain in healthy condition after breeding or ahead of migration or as they prepare to survive winter conditions.

Females may commonly have a more subdued plumage, which provides better camouflage and protection from predators when nesting and raising young.

Post breeding, when an impressive, flashy coat is no longer needed to attract a mate, males frequently undergo a molt into a basic plumage, losing their colorful feathers and instead displaying less vibrant, drabber tones until their image needs a revamp the following spring.

On hatching, many bird species are covered in a fluffy ‘natal down’. While in the nest, juvenile plumage develops, strong enough to support the young nestlings through their initial flights when they are ready to fledge. By their first winter, it’s usual for a partial or full molt to follow, and each year, the change between breeding and nonbreeding plumage can be rather dramatic.

One example is the male American Goldfinch, which changes from a striking yellow during the breeding season to a far less conspicuous olive shade once it has raised its young. Bright coloring helps to secure a mate and to drive away interlopers, but once nesting is complete, less bold colors help them to evade predators and lie low during the winter.

An American Goldfinch during the breeding season

An American Goldfinch in non-breeding plumage

Coloring Mechanisms

Birds’ feathers obtain their pigmentation through a combination of genetic factors and environmental influences. The presence and distribution of pigments called melanins and carotenoids control the coloring in a bird’s plumage. Melanins produce darker colors, including black, brown, and gray, while carotenoids are responsible for creating vivid reds, oranges, and yellows.

Genes are also a key factor in determining the types and amounts of pigments in a bird’s body. The genetic makeup of different bird species controls the production of each pigment, which leads to the vast variation in colors and patterns between species.

Environmental factors, including diet and exposure to sunlight, also affect a bird's coloring. Birds that eat food containing a high concentration of carotenoids, including fruits and insects, may exhibit more intense colors.

Flamingos are an example of how diet has a major influence on plumage, with their main diet, brine shrimp, rich in carotenoids. Sunlight can also change the appearance of feathers by breaking down pigments or enhancing their visibility.

Pictured: Greater Flamingo. Flamingos are an example of how diet has a major influence on plumage

Plumage as Communication

Not all communication between birds is vocal. Contact between pairs and family members is not limited to song or calls, but may also involve visual courtship displays, posturing, and showing dominance to protect territory or defend a mate.

Read on to learn more about the role of coloring and plumage in bird communication.

Courtship and Mating

Colorful plumage signals the age and potency of a bird, and the brighter the plumage, the greater the likelihood of successful and healthy breeding. Older birds, which may be in declining health, will usually have less rich coloring, leaving them lower down the desirability pecking order among breeding females.

The more eye-catching and impressive the courtship display, the better the chance of securing a mate. Some of the most memorable, elaborate displays feature mind-bending colorful choreography in front of contrastingly dull females.

One perfect example is the bird of paradise, which arranges its feathers into a glossy black parasol, with shimmering turquoise patterning and performs a lively routine for the appreciation of its intended brownish-gray mate.

Peacocks are famous for their ostentatious tail feathers, and spectacular, rustling courtship displays. Female peacocks are comparatively plain in appearance, and select mates on the basis of the most dazzling plumage, as this is thought to indicate the strongest genes to pass onto their offspring.

Pictured: A Female Peahen (foreground) and a Male Peacock displaying his train

Territorial Displays

Plumage can be used to intimidate possible predators or deter birds of the same species from encroaching on their territories.

Northern Pygmy Owls are a particularly clever example, with two ‘false eye’ spots on the back of their head, which give the impression that they are constantly watching and may strike out at any moment.

Scarlet shoulder patches on a Red-winged Blackbird are hard to spot in normal circumstances, concealed by upper wing feathers, and outside of their own territories, only the thinnest trace of color can be seen. However, in conflict situations, the bright red flashes increase in visibility, serving as a visual deterrent to rivals.

Fluffing of feathers and raising their crests are two further ways that birds make use of their plumage to inflate their size in an attempt to appear larger and more dominant to any approaching threats that enter their territory.

Pictured: A Red-winged Blackbird. In conflict situations, the bright red flashes increase in visibility, serving as a visual deterrent to rivals

Seasonal Variations and Molting

Birds’ feathers are at their height of vibrancy and color early in the year, when males of many species rely on eye-catching plumage to catch the eye of a potential mate. Bolder, brighter colors are associated with strong genes, robust health, and dominant character, and are considered superior and more desirable to less intense shades.

Once a pair has raised their final set of young, territorialism subsides in many species and there is no need to impress or attract a mate.

At this time, it’s common for both males and females to undergo a full or partial molt, developing a stronger set of feathers ahead of winter migration or protection against colder weather. Read on to learn more about seasonal plumage variations and the molting process in birds.

Seasonal Variations

Ahead of the breeding season, male birds are usually at their peak of colorfulness, using their bold plumage to catch the eye of a potential mate.

Some color changes can be particularly dramatic, with the Scarlet Tanager an intense red when mating, but molting into a drab greenish-brown once the fall arrives and it’s more beneficial for their survival to blend into their surroundings than to stand out.

Seasonal changes to plumage can signal a decline in territorial behavior in birds that are particularly aggressive or defensive when breeding.

Once breeding ends and they molt into less vibrant coloring, larger foraging flocks may begin to gather with birds feeding alongside their earlier rivals.

Pictured: A Scarlet Tanager (male) in breeding plumage

Molting

Feathers suffer from extensive wear and tear, and become less effective and more easily damaged with age or as a season progresses.

During the summer months, it’s necessary for plumage to be replaced, particularly ahead of migration flights when strong feathers make a huge difference in whether birds reach their destination safely.

For non-migratory birds, fresh plumage is also vital, with plumper less worn feathers offering better protection against cold weather.

Ahead of breeding, a further molt may occur, with feathers at their brightest when they are seeking mates and forming pairs.

While undergoing the post-breeding molt, where their appearance becomes more subdued and offers effective camouflage against their habitats, a noticeable change in behavior can be observed.

Molting birds generally keep a lower profile and are not as visible, tending instead to skulk in undergrowth or vegetation until their new plumage is fully developed.

Pictured: A Northern Cardinal molting after the breeding season

Summary

Recognizing patterns and colors in the plumage of birds is not only the key to identifying different species, but it also offers us an insight into non-vocal bird communication and the various signals and meanings that the display and color of feathers may convey to other birds.

From the spectacular, elaborate courtship displays of Peacocks and male birds of paradise, to the more subtle crest-raising in Waxwings and Herons, many birds use plumage to effectively communicate with other birds of their own species.

Many colorful birds will use their striking patterns or boldly colored patches to their own advantage, extending crest feathers so bright feathers are visible (for example Firecrests) or wing-flashing to signal dominance (e.g. Northern Mockingbirds).