Introduction to Feathers: basic structure and color

Melanin, the brown and black pigments, adds strength to the feather. You may have noticed that many birds, like most gulls and terns have dark feathers at the tips of their wings. The color is due to the presence of melanin, which helps slow the abrasion of these very important feathers.

Other pigments often seen in feathers are a group of several pigments called carotenes. These are the red, orange and yellow pigments. These are usually not produced by the bird itself, but are taken in during feeding. Flamingos, for instance, are (usually) pink because their diet includes many small invertebrates that contain high amounts of carotene. The flamingo’s body can’t use these carotenes and treats them as a waste product. The body uses the growing feather as a place to get rid of them. The same thing happens with people – humans that eat too many carrots will have a yellow-orange cast to their skin. And if you feed a captive flamingo on a diet high in orange carotene rather than their usual red, you’ll get an orange bird!

A color is not produced by pigment in feathers: blue. There are no birds that have any blue pigment. The blue color is produced by a combination of melanin and small bubbles in the structure of the feather. These bubbles bounce light around within the feather, off the particles of melanin pigment, and look blue to our eyes. This is usually called “structural blue.” The same thing happens to make the daytime sky look blue – sunlight bounces around off dust particles in the atmosphere and the sky looks blue. This is called the Tindall effect.

Most birds don’t have green feathers either. If you see a green bird, it’s not really green – it’s yellow (produced by a carotene pigment) with structural blue. One group of birds, the Turacos (a group of birds from Africa) do have a green pigment, called turacin. This is the only group of birds that are “actually” green.

So, the next time you look at a bird, take a moment to notice the feathers!

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