Ducks by a river?

Hi all,
 this is my first post, hope someone can help me.
 We have 4 chickens and 2 ducks, we are thinking about moving to a house that backs on to the river trent, if i let my ducks on to the river would they swim away or come back? they are very happy with use, but not to shore about this, can anyboby help please, Thanks Darren.

Yea i would keep them confimed to there house and make a fun so they cant go far.

Keep for for a couple of weeks cooped in then they know where home, safe and food is.

After they as long as they have easy access to get in and get out they should be fine.

would they be at risk from foxes, stoats, coypu, weasels etc or people with guns especially if they dont fly as well as wild ducks ??
R

If you feed them well enough you could end up with more ducks than you can shake a stick at !
Plus moorhens , coots and other freeloaders.
As mentioned before on a river there will always be predators and rats to contend with .