I would vote that it is a bit of a mutt. My swedish blues and blacks are mixes, and 2 of their siblings are yellow, whitish, and their beaks are getting more blueblackgreen every day... just a little semicircle of orange on the very front now.
Hi, the spots are not anything to worry about. It just happens to be the color of the beak on that particuliar duck. I have noticed it in younger ducks as they develop and change, but I also have mature ducks that have the same markings on their beaks.