Posted 06 May 2012 - 01:02 PM
This is a House Finch. Reds, yellows, and oranges in birds come from carotenoid pigments, and the birds have to acquire them through their diet, then modify them to use. Which means that if their diet changes or they're metabolically out of sorts during molt, the colors can come in funny. House Finches seem to be especially prone to this, so you'll sometimes see orange or even yellow instead of red.