The nest of the Rosybill is a very large cone shaped feature made of vegetation built on land but surrounded by reeds or other growth. 6 to a dozen grey eggs are laid in the top depression. The female incubates for about 26 days. The chicks follow the parents, learning feeding items and techniques by observation. Their flight feathers take a long time to grow in, but flight ability is not critical. They dive well as soon as they leave the nest, at about 2 days of age. During those first days, they are covered by the mother, from whose breast they gain the necessary oils to become water repellent. These ducks are seasonal migrants and they generally move as soon as the chicks can fly. The mature plumage is achieved on the second molt, at about 1 year old. The females breed in their first adult year.