Anna's gorget feathers are the iridescent, reddish-pink throat feathers of the male Anna's hummingbird that change color with the angle of light. This "structural color" is created by tiny, layered structures called melanosomes within the feather barbules, which reflect light without pigments. The gorget can appear bright and dazzling in direct sunlight but looks dull brown or gray in low light.
Thanks, you are welcome. It never ceases to amaze me how many different hues his gorget can display depending on the light, slight head movement, and how much he is trying to impress females or warn off males.
I recall being at the top of a hill and seeing a tiny flash of golden light a long distance away at the edge of a forest. It was only by using binoculars that I could make out it was a Rufous male flashing his gorget.
