Duckling malnutrition - in areas where ducks are regularly fed bread the ducklings will not receive adequate nutrition for proper growth and development.

· Overcrowding — where food is easy to come by, ducks will lay more eggs and the pond will become overcrowded. This makes it more difficult for the birds to seek out healthier food sources and increases territorial aggression, especially during mating season

· Pollution — what happens to all that bread that is not eaten? It causes algae growths, pollution, and can eventually eradicate fish and other life in the vicinity.

· Diseases — a diet rich in carbohydrates leads to greater fecal production and bird feces easily harbors bacteria responsible for numerous diseases including avian botulism.

· Attraction of pests — Rotting leftover food attracts other unwelcome pests such as rats, mice, and insects. These pests can also harbor additional diseases that can be dangerous to humans.