Thought I'd add something with regards wing clipping - don't be under any illusions that KC's can't fly - they can, and will. I had seven (one drake, six ducks) and when they reached about 7 months old, they all took off, never to return. I have not had the same problems with my Aylesbury's (too heavy), Appleyards (same), Runner Ducks (can't be bothered to fly, just run everywhere), or Geese (Just can't be bothered to fly!!!). I wing-clip all my chickens (apart from the Brahmas, who can't be bothered), and don't worry about my ducks now - hindsight is wonderful. If I had KC's again, I would definitely clip them........
Hope this helps.
Good Luck.