The bumpy-faced waterfowl can be found across the United States, but in almost all cases the birds are domestic versions of the wild ducks. Here's how to know which is which.

DEAR JOAN: On Dec. 8, my wife and I saw a Muscovy duck in the Larkey Park neighborhood. I know these are generally tropical birds, and this seemed an unusual sighting, as we’ve been here 20 years and ...