We plunge underwater to observe habits of juvenile Zalophus californianus. Or, in the words of Ivan, our dive master extraordinaire, to play with youngsters. And play is what we try to do. The result is, to be honest, that we are being played with. Sea lions treat us as clumsy companions who cannot swim fast enough and have to be jolted into action by deftly applied bites. We develop various techniques to keep them from nibbling on our wet-suited bodies. It's a good thing they seem to have preference for yellow, which means that our snorkels, fins and secondary regulators are in greater danger than our fingers.