blackshoulder question?

[DAS]

In general, the diversity of bird feathers’ colors can be explained by just two factors: pigments, and simple structures in the feathers that interfere with incident light. Pigment particles are embedded into the newly grown feathers during the molting season.

copied this from webexibits.com

 

[new 2 pfowl]

Also, “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).”

from http://www.stanford.edu/group/stanfordbirds/text/essays/Molting.html