Ducks have been domesticated as pets and farm animals for more than 500 years, and all domestic ducks are descended from either the mallard or the Muscovy duck. Mallards, especially, are easy to crossbreed with other types of ducks, and mallards often hybridize with all types of ducks at local ponds. This can lead to very unusual feather shapes and color patterns that can be confusing to identify.
Most towns are blessed with parks to take their children on a nature hunt. Our town, LaPorte Indiana, is blessed with many parks inhabited with geese, ducks, and (the even rarer) Swans that make for excellent photography sessions.