Editing Musk duck (section)

===Reproduction===
The musk duck breeding season varies with rainfall and water levels, but is typically between July and January, with the greatest number of clutches laid in September or October, the austral spring. Despite a number of more general studies, little is known about musk duck breeding.  During breeding season, they give off the musky odour from which the species derives its common name.  Also, in the season males advertise themselves loudly with a repetitive sequence of sounds: first, a ''ker-plonk'' splash made with the feet on the surface of the water; then two soft, sharp ''cuc cuc'' calls; then a loud whistle and a deep grunt. This sequence can be started at any time of day or night, with or without an associated visual display, and repeated every 4 or 5 seconds for as long as half an hour at a time. Although male musk ducks have a large leathery lobe below the bill and this swells during the breeding season, it is not connected to the vocal cavities and appears to be purely for visual purposes.

Mating is thought to be promiscuous, quite possibly on a [[Lek (animal behavior)|lek]] system like that of the [[kākāpō]] (a very large, flightless parrot found only in [[New Zealand]]), but this remains uncertain. The male plays no part in building the nest or raising the young.

Females select a secluded location for nesting, usually in tall reeds well away from land and protected by deep water, or under the cover of overhanging shrubbery, but sometimes in a range of innovative places, such as on a stump, in a hollow log, or even under an upturned boat. The nest is a simple platform of trampled plant material with a slight cup, lined with fine plant matter and, after the [[Egg (biology)|eggs]] are laid, plenty of down. She seems to be unable to carry nest material and must rely on whatever is within reach. With the nest complete, she pulls reeds down from overhead to make a canopy, hiding it from view. When leaving the nest to feed, she slips quietly into the water and submerges, not surfacing until she is well away from it.

Clutch size is unknown: as many as 10 eggs have been counted in a nest, but it seems likely that this is the result of dump nesting: three or four eggs are considered more likely. In most cases, only one duckling survives, sometimes two. They are able to swim and dive within a few days, after which they probably leave the nest. Young stay close to the mother for several months at least, sometimes riding on her back to begin with. They can peck at food items on the surface and dive a little while still quite small, but the mother continues to provide the bulk of their food until they are almost full-grown.