Ducks mate using sexual reproduction, which carries out in monogamous or polygamous mating systems, depending on the species of duck. Some ducks retain the same partner during their lifetime, forming monogamous partnerships while others accept multiple partners. Some breeds take long periods establishing good life partnerships while courtship in many other species takes place briefly and lasts only temporarily.
Although ducks classify as one group of organisms, they exhibit many different mating styles and habits. Some ducks, such as Canadian geese and mallards, form monogamous partnerships. Male geese of both species perform long and complex mating ceremonies, complete with displays of colorful plumage, attempting to attract perfect mates. Males look to outdo each other in size and brilliance of feather colors. Larger and more colorful males attract females, as large size and bright feathers signify strength and good health.
After selecting partners and mating, females return to nesting grounds, searching for safe places for hatching and raising chicks. They seek out places with adequate food and shelter, and may ward off non-partner males. Rather than seeking out single females, males of polygamous species, such as ruddy ducks and pintails, establish territories. They claim several females in their broods, mating with all. Ducks of all species, regardless of whether monogamous or polygamous, generally reach sexual maturity at ages two or three, when mating begins.