There are several different varieties of mallards. There is the Mexican duck, which is found in Mexico and the southwestern United States, which is a subspecies of the mallard. The Hawaiian duck, found in the Hawaiian Islands is a separate species that is believed to have evolved from the mallard. Mallards will also hybridize with other species of ducks. Mallards with breed with other wild ducks or domesticated species, most of who's ancestries can be traced back to mallards. The duck in the front of this photo is a female hybrid between a mallard and most likely a domesticated duck.