How do parrots get their colors?

Parrots get their colors from pigments in their feathers, and from the structure of the feathers. The three main pigments are yellow, red, and black. Black pigment shows up as grey, black, or blue depending on how the structure of the feather reflects light. A slightly iridescent grey feather looks blue. An iridescent grey and yellow feather looks green. Some parrots have feather structures that reflect ultraviolet light, which makes a color that parrots can see but humans can't.