Male ducks, known as drakes, fertilise the eggs of female ducks, known as hens, by copulation. During mating season, which begins in early spring, copulation often occurs following a wooing ritual. Once every four to five days, drakes must mate with hens to ensure fertilisation.
According to PBS.org, ducks engage in internal fertilisation, which occurs within the hen’s reproductive tract. This safeguards the egg’s development.
According to SouthFloridaMuscovyDucks.com, drakes perform courtship rituals include head bobbing, exaggerated feeding movements, preening, and counter-movements. They also produce courtship-specific cries and stand in specific positions, such as with their head and tail held high.
According to About.com, the reproductive organs of birds and mammals are distinct. When ducks are ready to mate, their reproductive organs grow within the cloaca, a body exit. Each drake and hen possesses a cloaca. Once a hen accepts a drake, the drake balances atop the hen and copulation happens. A penis is formed by an expansion of the cloacal wall via lymphatic fluid, allowing ducks to mate in the water without the sperm washing away.
The egg and sperm join within the hen to form a fertilised egg, known as a zygote, which is surrounded by a protective shell. Brooding is when the hen lays an egg and sits on it until it hatches. Typically, drakes leave the hen to her brooding.