Sure, you could color these birds the normal way, even going so far as to look up information about what colors should be used, but where's the fun in that? Instead, for each color, look up its complement, and use that.
Caw! Screech! Hoot! For those who don't speak bird, I'll translate: These enamel pins think your hair would be ideal to nest in, and they're willing to make this a mutually beneficial transaction. They get a place to live, and you get a cool pin.