Puddle ducks are typically birds of fresh, shallow marshes and rivers rather than of large lakes and bays. They are good divers, but usually feed by dabbling or tipping rather than submerging.
The speculum, or colored wing patch, is generally irridescent and bright, and often a telltale field mark.
Any duck feeding in croplands will likely be a puddle duck, for most of this group are sure-footed and can walk and run well on land. Their diet is mostly vegetable, and grain-fed mallards or pintails or acorn-fattened wood ducks are highly regarded as food.