I have drake that a member of this forum guessed as a Khaki mix back in September. I sent a picture in at that time (9.17.2009) showing my drake with a beautiful emerald green head. He looks like a Mallard without the white ring on his neck. Now a year later he is much larger than my other Mallards. Anyway, a couple months ago, his beautiful green head turned brown matching the rest of it's body!? I thought maybe he was just a molting, but it has stayed brown. Any ideas?