The two major duck groups, puddle and diving ducks, differ in several ways. Diving ducks are, as their name implies, adept at diving and obtain most of their food this way. As a group, they are not accomplished divers, but adults dive occasionally and ducklings do so frequently. Puddle ducks feed in the water along the fringes of islands and shorelines and on dry land.
Puddle ducks are excellent swimmers, sure-footed on land, and swift agile fliers.
Speculum color varies from species to species and may function as a flashing signal to help keep a flock together. To the human observer, the speculum is often a telltale field mark. They generally mate for the first time when a year old. During courtship, drakes chase the hens and engage in fighting, ritualized movements, posturing and calling. After mating, the drake leaves immediately, or he stays with the hen while she is laying and then departs soon afterward.