Damaging for ducks
But the threats don't exist only for humans. The ducks are at risk too. First, the "go-to" foods people often throw to ducks and geese—various forms of bread, crackers and granola—are ultimately bad for the birds. Ducks are genetically designed to eat the wide variety of insects and invertebrates that live in their habitat, as they are critical sources of nutrients, but they will learn to rely on handouts rather than foraging for these natural sources of energy.
Feeding ducks and geese bread, crackers and other unnatural foods is bad for the birds. Waterfowl are genetically designed to eat a wide variety of insects and invertebrates that occur naturally in their habitat and provide critical nutrients.
Encouraging the presence of mallards in urban areas could actually drive other duck species into extinction. The Florida Fish and Wildlife Conservation Commission reported that, in Florida, an estimated 12,000 mallards are purchased annually at feed-and-seed stores for seemingly harmless domestic purposes, such as Easter presents for children. But, after a while, many people simply release these ducks into their neighborhoods.
Wild mallards do not occur naturally in Florida during mottled duck breeding season, but people often unknowingly release domesticated mallards during this time. The mallards proceed to mate with mottled ducks (which have a small breeding population already) producing a hybrid that is fertile and thus able to further spread the hybrid gene. In essence, the conservation of Florida's pure mottled duck is at great risk, a prime picture of the kind of damage these "urban" mallards can cause.