One thing I do with my drake, when he gets too testy/moody/grumpy/bored/or wants my attention and turns to biting, is kind of a variation on flipping them on their back. I can never seem to get him over while on the ground and I am afraid of hurting him, so I started pickign him up and then just flipping him over on his back that way. He bends his neck over his belly and stares at me through his big feet. I put him down and he stops biting.....for a while. until he's moody/grumpy/bored again!
