Several views of the same individual male Anna's Hummingbird (Calypte anna) — photographed across from Westside Park on 25 May 2012.
Because the color is dependent on the microscopic structure of the feathers and the refraction of light, it changes with the viewing angle.
From The Birds of North America account by Clark & Russell (2012):
Lesson regarded it as one of the most beautiful hummingbirds, on account
of “the bright sparkle of a red cap of the richest amethyst...” on the
male’s head, and so named it after the duchess of Rivoli, Anna de Belle
Masséna. Gould (1861) placed it in a new genus, Calypte, for “not only the throat, but the entire head as glitteringly resplendent as if they had been dipped in molten metal”.
Lovely series of images!
ReplyDeleteOne the most exhilarating bird watching experiences was when I somehow got between a female (sitting on a perch) and displaying male. The startling image of the male descending towards us and then, just at the bottom of his swoop, the simultaneous "POP!" and brilliant flash of color. I was ready to marry him right then and there.