The hen makes a variety of quacks. The drake utters reedy quacking sounds and, during mating season, a sharp single or double-noted whistle. The mallard's broad wings and relatively short tail may create the impression that the wings are set farther back than on most ducks. Mallards are swift fliers and excellent swimmers. They may feed and rest in the company of other puddle ducks, including northern pintails and black ducks.
Mallards eat a variety of natural and human-produced foods.
Ducklings feed mainly on insects, particularly mosquito larvae, and also on crustaceans in addition to plant parts. When natural foods are plentiful and available, mallards prefer them, but when ice closes up marshes, lakes and ponds, they head for dry land and corn. Perhaps more than any other duck, however, mallards are notorious for feeding in farm fields where they search for grain in the remaining stubble of corn and sorghum fields. Mallards travel up to 25 miles for food. Often they make two feeding flights per day, one at dawn and the other in late afternoon.