I used to do this with my Parakeets... I would imitate the calls and sounds they would make just to mess with them. I had an obnoxious female that would make the angry "Chit Chit Chit" noise at me all the time. I would do it right back at her. She would get really quiet and then get curious. She was never a very friendly bird, but making her noises back at her got her from hostile to tolerable. When I repeated noises back at my dad's keet, he would get all excited and want to play. I think he thought I was a giant budgie Now I find myself doing the same thing at the ducks. I can't do the quack very well, but there are a couple of sounds I have down. Since I started doing it, they are less skittish. Hard to describe the individual calls, but I am getting pretty good at the angry noise and the worried noise. I don't think my voice can do the "is everyone ok" peep. Am I the only nut doing this? Anyone else learn to speak duck?