I have a lake behind my house. I raise ducks , i hatch them every year. Pekins and several other kinds. I put them to free roam when they're about 8 weeks old..or fully feathered. It's true that predators can get them, but i've had the same number out there for 3 years..snapping turtles and hawks generally get them when they're small ducklings..I have lost a couple ducks..but it's from Dogs of the neighbors and not racoons or other predators. They do stick around..they run up when they see my car they run up to the yard. They come right up to me. They have a coop that they can sleep in if they choose at night, some choose to stay there, some don't. The ducks sleep out in the water away from shore. So the answer is..they can go out at around 8 weeks. (6 weeks if they're fully feathered and they'll be fine) I feel ya with the messy pen..i love my ducks, but man by the time they're a month or two old I'm SO GLAD to not have to have the pen so much!!