The Ring-necked duck is one of the few ducks that nest in marshes and boggy ponds. In breeding season its habitat is in wooded country near lakes, sluggish rivers, ponds, estuaries and marshes. They probe the bottom of these bodies of water for seeds, aquatic plants, crustaceans and snails.
The males are stocky and mainly black with white flanks and a grey bill with a white band near the tip. The female is a brownish grey with a whitish eye ring and like the male, a grey bill with a white band near the tip.Their eyes are a dark yellow. The males crown feathers are long and erect which gives the head a triangular appearance.
They nest on the ground in vegetation near water, usually near the shore of a lake or pond.The nest is a hollow in the ground lined with grass, down and feathers. The eggs are olive grey or olive brown and are hatched after 25 to 29 days.The incubation is done only by the female.