most domestic ducks cant fly that well except for muscoveys and mallards and calls . rouns and aylesbury cant get off the ground but i have heard that runnersand cambells can fly a bit . But i dont think they can fly over a fence and such .
So Sara what breeds are considered heavy if you don't mind me asking? When I look on the hatchery sites they don't identify heavies vs lights. Not that I've noticed anyway.
Muscovies, while they can fly, they don't usually fly away and leave your farm. They are more like lighter breeds of chickens and will fly for a short distance, across a fence, or something along those lines, but not fly away like a mallard will.
My rouens, runners, and cayuga cannot fly, though one runner and the wide-bodied cayuga have gotten themselves up to a chicken nest box about three feet off the floor!