They don't make the noises that mallard deriviatives (all the regular ducks) make. The females make a "trilling" noise that is very pleasant and the males usually only hiss if "trying to make a point" to an "intruder". They don't need swimming water like other ducks but mine loved a splash and bath even in the cold. I don't have them anymore....too difficult in the cold to keep a coop clean with them! Good luck with your hatch!!
Thank you so much for posting those pics. The birds I saw looked a lot like those in the top pic. I confess I took his word for it that they were a pair, and didn't pay close enough attention. It is possible one of them had a crest and I just didn't notice. Time will tell. From what I'm reading, I really like the sound of Muscovy's and now I want some so if this doesn't work out I might find myself actively looking for eggs in the future. Enablers. Gah!