The mallard is the duck most North American hunters cut their teeth on, and the one most people picture when they hear the word 'duck' — green-headed drakes, mottled brown hens, white tail feathers curling up over the back. They're the most abundant duck on the continent and the genetic ancestor of nearly every domestic duck breed.
Mallards are dabblers, not divers. They tip up in shallow water to feed on seeds, aquatic plants, and invertebrates, which is why flooded corn, sheetwater on stubble fields, and shallow marshes hold them so well. They pair up in fall on the wintering grounds and migrate north together — which is part of why early-season birds decoy harder than late-season pairs that have already seen a season of pressure.
The Mississippi and Central flyways carry the bulk of the continental population. Prairie Pothole breeding habitat in the Dakotas and prairie Canada drives annual recruitment more than any other single factor; wet springs produce the big fall flights hunters remember.