I have had mallards in the past and liked them, they were free range all the time and were that way for at least 4 years. My first mallards(first ducks also) actually did stay in a pen. Their names were Sparky(drake) and Alexis(hen), they lived with 4 chickens. One day, when I was at school, my uncle came over and was cutting wood when he heard the chickens and ducks going crazy, so he quickly grabbed a gun and went to see what the racket was about. A mink had gotten in the pen and already killed 2 chickens and Alexis when my uncle came and scared the mink away. The mink slipped into the pond that was right near the pen and my uncle shot it while it was swimming. I got to see the dead mink when I got home. Years later, my grandparents got me some ducklings and they grew up just fine and one of the hens even hatched a brood of eggs. We counted the ducklings when momma brought them to the pond and there was an unbelievable 15 or 18 ducklings!!! One morning, when I was going to school, I insisted that I see them before I left and my mom took me to the nest. When we came upon the nest, horror filled me; dead ducklings strewn about, no mother to be found. I leaned over the middle the nest and seen some movement in some brush about 2 feet away, I looked and found 3 alive ducklings, huddling and shivering. We raised the ducklings and they turned out to be 3 drakes. They lived a few years ranging with the chickens and turkeys, until they were picked off one by one, taken by various predators. I don't have any right now, would like to, but I don't want to deal with the mess again, and we have more predators now than we did back then. Oh, we did find the moms body, headless and 300 feet away from the nest.