We have ours in a covered run, and their coop. The run is 12x8 one one side and the coop is 8x4.The other side has a run 12x8 and the coop is 4x6. We open the middle of the run so they can go on both sides. We have 2 trios in that size, and have held at least a dozen at a time,but they are let out all day to free range and were only held there at night, or if we were not home. I have the runs split for when we have babies, so I can keep the broody separate!
If you do not clip their wings Muscovys will fly, but stay close. Mine have never flow more than a football field away from their pen!
We don't clip, and that is why we have the covered run, so when we don't want them to wonder they are kept in the run!
They get farther on foot, than they do flying! LOL!
Brenda
They will hatch their own eggs, they are very good at it! I had a clutch of 23 eggs last spring and my hen hatched out 22. It was so amazing!
I never expected that many to hatch.