the color of Crows

You know that Crows are black, so why am I writing about the color of Crows?

This is why…

Look how colorful this adult crow is — showing off its pale iridescent brown and blue feathers.  What happened to the glossy black color of this crow?

This photo image is not due to the way the light happened to hit the Crow on this spring morning.  It is instead what happens to Crow feathers after most of a year of use.  The melanin pigment that makes the feathers dark brown to black has faded to a rusty brown color, and the structural elements covering the melanin granules in the feather that made them look shiny or glossy have broken down.  Now, tiny air gaps in the feathers simply reflect short wavelengths of light, which we see as blue.  And the combination produces the blue-brown look of this crow’s plumage.

Crows molt once a year at the end of the breeding season.  As the new feathers gradually lengthen and replace the old ones, high concentrations of melanin pigment are deposited in the shafts and barbs of the feathers making them look black, and a layer of keratin laid down on top of the melanin granules in the barbs will make the feather look glossy.

A crow hunting on the grass in the backyard last fall was a much darker color after molting new feathers.