The porpoises and whale themselves, in their quests for entertainment, often created problems. One summer a fashion developed in the training tanks (I think Keiki started it) for leaning out over the tank wall and seeing how far you could balance without falling out. Several animals might be teetering on the tank edge at one time, and sometimes one or another did fall out. Nothing much happened to them, except maybe a cut or a scrape from the gravel around the tanks; but of course we had to run and pick them up and put them back in. Not a serious problem, if the animal that fell out was small, but if it was a 400-pound adult bottlenose, you had to find four strong people to get him back, and when it happened over and over again, the people got cross. We feared too, that some animal would fall out at night or when no one was around and dry out, overheat, and die. We yelled at the porpoises, and rushed over and pushed them back in when we saw them teetering, but that just seemed to add to the enjoyment of what I'm sure the porpoises thoguht of as a hilariously funny game. Fortunately they eventually tired of it by themselves.
Karen Pryor, Lads Before the Wind: Diary of a Dolphin Trainer
behavior, dolphin