How do they get back or does the stream not rush? Back before I adopted my first Muscovy from the river below our home there were two of them they would float down the river and fly back I don’t think it would have been much fun to swim upstream. It sure was a cool site to see them flying though.I agree.
But just as a personal experience, my ducks will float down the creek in the winter/spring, they will be gone all day and will come back once its bedtime.