Mallard ducks are very common in the wild and can be found in the spring in many people-oriented areas like golf courses and parks. If you have found a mallard's nest, or found yourself incubating deserted mallard eggs, the next step is to take care of the mallard ducklings.
Put together a home for your mallard duckling. Use a dog crate or box with a roof. Fill the box or crate with several blankets for nesting. Put a heating pad on the roof of the box, set on low, to keep the duckling warm. Keep this heating pad on 24 hours a day until the duckling is 10 days old. Then switch to heating the box only at night.
Put out food and water for the duck. Fill a shallow dish with water and another shallow dish with duck food mixed with a small amount of water. If the duck doesn't eat by himself, spread some of the food on his beak. Make sure that you give the duckling only a shallow dish of water; ducklings can drown in very little water.
Fill your sink with a couple of inches of water once a week for bathing your duckling. Allow the duck to splash and bathe himself, but supervise him carefully; until ducks grow their adult feathers, they are not buoyant and can drown.
Use diapers to keep the duck clean. Baby diapers are ideal for ducks until they get too big. Ducks that have outgrown baby diapers can wear expandable harnesses to keep them clean (available at pet stores).
Although mallards are wild animals, there is a growing movement of keeping ducks as pets. Give ducklings stuffed animals for cuddling.
Keeping animals like ducks is illegal in many areas. Research your city's laws about wildlife and farm animals before you adopt a mallard duck.