I have a really weird duck... She's a blue crested duck, about 4 months old, named Floxy Cleopatra. She is smaller than the other ducks, has longer / fluffier feathers, has two crests (one split down the middle), and she whistles. She's done it since she was hatched, and now as an adult it sounds like some sort of wild bird call. We didn't even know it was her until a few days ago. Has anyone ever had ducks that do this? What does that call mean?