This is from
http://theselfsufficientgardener.com/muscovy-ducks-a-comprehensive-guide
(sadly, the first few paragraphs are about using them for meat, but here is the care instruction)
Care
Like all animals, Muscovies require clean water, however, Muscovies require much less water than other ducks. A children’s “kiddie pool” is sufficient and a smaller feeding trough would work as well. In Winter, I use a rubber pet bowl that I can step on to remove the ice. Muscovies only need enough water to submerge their nostrils. Muscovies would, however, welcome deeper water to swim in. Like all ducks, Muscovies are messy and tend to slosh water and foul it. A kiddie pool should be changed at least once a week, if not sooner. The fouled water is rich in nutrients and excellent for irrigating plants.
Muscovies should be fed a protein rich crumbles or pellets. It is absolutely essential that the feed be free of any medications. Younger ducklings should be started on crumbles and not given any whole grains until they are one month old. The ducks should also be given grit to enable their gizzard to grind the food. Greens should make up 1/3 of the diet. I let my Muscovies free range, so I only give them enough commercial feed to keep them coming back at night. You should keep them out of the garden and away from vulnerable plants, however. I hope one day to get away from commercial feed. I also give them table scraps. When writing this article, I read about Muscovy owners who set out solar LED lights to attract flying insects solely to feed their ducks.[v] (Gotta try that!) Every evening, they see me and run towards me. They are like puppies, looking happy and wagging their tails! I then put a pail with a small amount of feed in their pen, the Muscovies run inside, and I close the door. In this regard, they are much, much easier than chickens. The following morning, I let them all out for water. I can’t keep the water inside or it would make a huge mess. One thing to be ware of is that Muscovies do not fear vehicles. Several times, I have heard cars honking at the clueless ducks- just standing in the road! I am lucky that I do not have canard à la presse![vi]
Ducks are covered in an insulating layer of down, but their feet are still vulnerable to the cold. Their pen should have a thick layer of clean, dry straw or wood shavings to protect their feet. In the summer, ducks will need water and shade. Clean water, sanitation and space, along with good nutrition are essential to the health of any animal. Muscovies are much hardier than chickens and more resistant to disease.
…………..
from
http://journeytoforever.org/farm_poultry.html
Muscovies are unique, the only domestic ducks that aren't derived from mallards. They come from South America and they're tree birds rather than water birds. So they don't need a pond to swim in (they do need water, but a large basin will do). And they fly. They're bigger and heavier than other ducks, and flying gives them large and powerful breast muscles, and strong, meaty legs. Muscovy breast looks like a fair-sized steak, you wouldn't guess it was duck.
