of course ducks are used as food. duck is an animal. basically, anything living is some sort of food you eat.
edit:
Ducks are used in a wide variety of cuisine. There tends to be more dark, fatty meat and the meat tastes gamier.
P.S. not all living things are edible, eat unknown foods at own risk
They can be used for food and hunting for entertainment.
Eagles will take ducks in flight, for food. Ducks eat grasses and sometimes, small fishes. Eagles have talons, ducks have webbed feet. Eagles have beaks, ducks have bills.
I am assuming you want to know how to keep your chickens from eating the ducks food and the ducks from eating the chicken food. First ands easiest way is to keep the ducks separate/feed separate. If this is not possible and they free range together try placing the ducks food in an area surrounded by water, adult chickens by nature don't like to get wet, ducks do. If the duck food is only accessible by crossing a water barrier then the chickens will stay out of it.
Food
Except when paired off during the nesting season, ducks form flocks through out the rest of the year. Throw food to a flock of ducks on a pond and they will scramble in a frenzy to get to the food - no cooperation there.
ducks
their beaks
yes
They use their short beaks to gets its food.
Ducks can generally get by on chicken food, but do better on a game bird or meat bird feed, which is a little higher in protein I believe.
The ducks definitely uses their bills its the only way that they could eat.
Ducks and Mushrooms/Carrots