I have White Call ducks, Australian Spotted, Black East Indies and Mandarins. I've had to build flight pens with small spring fed ponds in them to keep preditors from getting them, keep the ducks from flying away and to keep them from mixing. Alot of time, work and money involved with those pens, but I enjoy sitting and watching them. Out of all those, if you aren't going to pen them up, the Australian Spotted would probably be more apt not to fly away. The Mandarins are the quitest if noise is a problem, but they are hard to tame/calm down and are usually stand offish. Calls are noisy, after all that's what they were originally bred for, to call in the wild ducks for the hunters (now they use duck calls instead of Call Ducks!). Calls can fly away, especially if they do call in wild Mallards and decide to join up with them. I've had large breed ducks in the past, I had to keep them penned up too because of coyotes.