One of my lil call drakes did this when I held him on my lap, I dont think it was his way of saying he was happy. More like a let me go right now kind of reaction, he would begin to shake and then pounce up at my face (never got there b/c he was so small) I thought it was so funny but I never got the feeling he did it cause he liked me. My geese do this when I catch them and sit down with them, they begin to vibrate but they never lung at me, I wonder if this is the same thing, has anyone else ever had a goose do this to them? My Mallard hen never did shake or pounce at me she would set quietly on my lap and just nibble every thing, I always thought that that was what a happy duck does, am I wrong?