In the twenty-first century it may be reared for meat and eggs, but is most often kept for ornament or for showing. Ducks may lay some 100–150 large eggs per year; at the beginning of the laying season the eggs are dark and may be almost black; they gradually lighten to the usual pale greenish blue or almost to white by the end of the season. If they are to be hatched, the incubation time for the eggs is 28 days.