Mating is polygynous. Of these the Fulvous Whistling Duck, Dendrocygna bicolour , lives in North and South America, Africa and India. The sexes are similar, and they are monogamous, possibly forming pair bonds for life. They are commonly seen perched in trees but should not be called tree ducks. Some species are nocturnal and little is known of their biology.
Pairs preen each other an uncommon trait in ducks.
They are named for whistling call which is often given in flight. They are considered a pest of crops in some places. The nest can be built in several localities including a hollow in a tree, on large horizontal branches on top of bromeliads or on the ground. The breeding season is very variable and ill-defined even with a single species on a single island, but June to October are the more commonly used months. Eight to fifteen eggs are laid and in some species at least, both sexes take part in the incubation which takes 24-30 days.