Yes, these show up around the region every once in a while. Below is a message I posted to Tweeters asking the same question in Jan 2015. At the time, Sammy Catiis replied, calling this a “structural color morph.” They sure are gorgeous, and surprising.
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Trileigh Tucker, PhD
Professor Emerita of Environmental Studies
As I was walking past a densely overgrown wetland on this gray afternoon, a movement caught my eye, and for several minutes I watched a golden hummingbird foraging in the shrubbery. I have to conclude it was an Anna’s because, well, it’s January in Seattle. But I was pretty surprised how consistently golden it looked. I’ve seen that gold plumage tone occasionally and briefly on sunny days when the sun angle was just right or when I was using a flash. But today was a gray day here, and the bird was deep in a shady shrubby area, and the light coming behind me was brighter but still gray, and I wasn’t using a flash. He or she stayed golden-looking the entire time, never looked green, even when it was under a leaf. Maybe a juvenile?
Photos are pretty uniformly poor because of the poor light and the photographer’s limited skill in making appropriate adjustments, but you can still see what I mean by “golden”; take a look if you like:
This morning, at Bellevue High School, I saw a female Anna’s Hummingbird that was golden in color where it is normally green. The chest was whiter than normal grayish color. And the size seemed slightly slimmer than normal. Has anyone else seen Anna’s hummingbirds that are yellowish, with a tinge of green?