I am no expert but have had free range muscovy ducks (actually South American geese) for 2 1/2yrs now. With natural brooding, and a disturbing amount of duck sex, we've gone from 2 originally to 12 now, with 5 males going into curries, soups and whatnot. I have given a dozen week old ducklings away to what seemed good situations as well. I think we've had 36 ducklings and 29 made it to maturity with minimal help from me beyond allowing nesting sites to exist that they found themselves, like behind my
wood pile and in blackberry brambles. I find about 1/2 an egg per day per muscovy in the mild winter here, double my
chickens' production.
The males can be a problem but mine were not as far as I saw any more than other females. I would bet the more males you have would exponentially increase the risk, and this was reflected in how my first brood all survived while subsequent broods lost up to 3/6 when having more males around and also when I had to pen them up briefly in a 300sq ft enclosure. The biggest risks have been my neighbors' cats and dogs when the mother took them out to show them her foraging spots. I am going to be bringing in new male breeding stock shortly to stop the inbreeding that I cannot otherwise stop and leave them free range.
Muscovies are much tougher than any of my
chicken breeds and it seems like you have to work to keep them from multiplying on their own. It may seem harsh but I think the ones who survived are stronger and better foragers for having been brooded naturally and those that died went to
feed the soil ultimately. True ducks may be different but given
trees and fences to fly to Muscovies are much tougher than you'd think. I broke up a male fight today (they will be curry soon), and they have big claws and strong wings. I have also taken the approach of having a lot of escape routes and perches rather than penning them in, and have a big livestock friendly dog that looks out for them but haven't had problems with raccoons yet here right next to a national park.
