All 4 of my Muscovy's roost. The girls are very good at perching on a small high up roosts, Godzilla, our drake, is not so graceful, he roosts about a foot off the ground and just steps up onto the perch. I figure they wouldn't do it if they didn't want to, those four don't do anything unless they want to.
Their flight feathers are clipped but they can still get about 4 feet off the ground for short distances. I am contemplating not clipping them this year, but I think my husband will flip out if they roost on his truck. Maybe if we build them loads of other places to land they will not land on the cars? Wishful thinking I know. Or maybe that will be incentive for him to always park his truck in the garage...hmmmm.