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. Mallards mature sexually in their first year. A period of social display begins in late fall and continues through winter into spring.
Males grunt and whistle, swim, pump their heads, and preen in front of the females.
The hens stimulate the courtship with calls and their own stylized body movements. Most pair-forming activities occur on the water, although chase flights in spring are prominent courtship rituals. Most hens have chosen their future mates by the time mallards arrive on the northern breeding grounds in spring. Mallards primarily nest around freshwater lakes, ponds, marshes and reservoirs across Pennsylvania, but it's not uncommon to find them nesting in agricultural fields and in residential areas. The hen typically nests within 100 yards of water, on the ground in a depression lined with reeds and grasses, with soft down added from her breast.