We call him The Interloper. He arrived in mid-January, when this photo was taken, and has been here ever since. I'm surprised that not only did he show up in new territory during the winter, but that he managed to keep it.
When I first saw The Interloper, I thought the sun was reflecting oddly off his wing feathers. Turns out that it wasn't the sun: his shoulders and wings have red-tinged feathers instead of the traditional black.
So far he's kept his red epaulets, but red-bellieds don't molt until late summer so that's not a surprise. Here he is from a few weeks ago:
Wish he was banded so we could tell if his feathers grow in normally during this season's molt (since if they do he'll just blend in with our other red-bellieds).
I've spoken with a couple ornithologists and biologists, and don't have a definite answer for this coloration, other than some type of genetic mutation. I believe this could be an example of erythrism: when black or brown feathers (or fur, hair) take on a reddish tint. This is different than the more commonly seen red, orange and yellow variations due to the manufacture of carotenoids based on diet.
We'll wait and see what the late summer molt brings!