1 When yellow ducks grow up, their beaks are long, wide and flat, and there are 1 hard bean-like protrusions at the tip of their upper beaks. The neck of meat ducks is thick, while that of egg ducks is thin. Male ducks are larger, with wider backs and shoulders. Female ducks are smaller than male ducks, with longer body and thinner neck.

2. The head, neck, upper and lower bodies of the Black Sea Muscovy Duck male are all black, and the upper body is slightly shiny. The wings are covered with dark brown and silver gray feathers, and the tail is black and long and pointed. The top of the female bird's head and back neck are dark brown, and the head side, neck side, chin and throat are grayish white, with tiny light brown spots on the neck side, and the upper body is dark grayish brown with grayish white end spots, and the chest side and both sides are also grayish white end spots. The chest and abdomen are grayish brown, and the abdomen has a little less obvious grayish white markings.