Big Males
This is a typical Muscovy male. As with most ducks, this male has nothing to do with brood rearing.
I failed to get a male and female together to illustrate the 2x the size difference – a far larger size differential than most waterfowl.
Muscovy and Mallards are the two ducks that have repeatedly been domesticated. Interestingly, it only takes a handful of generations before both become all white in domestication.
Domesticated Mallards are far more common – they even have a regularly used name – Peking Ducks.
-Frank