How does a pirate keep his parrot from falling off his shoulder?

While some pirate may have had a pet bird, doubtful, a bird will hold on with its feet and claws without any problem. Parrots, in particular, have strong claws and feet for climbing and gripping. Birds tent to be flock creatures and want company. They sit on the shoulder of the person they feel is part of their flock or their mate. I have my Cockatoo on mine as I write this. As long as you don't make too violent a movement, there isn't a problem.