A young plesiosaurus who met Hugh while imitating the spying efforts of his elders. Though his kind communicate through telepathy, Piko evolved to speak after hearing enough language and spread this knowledge to the rest of them. As plesiosaurs seem to have no concept of gender, many speculate they might not be divided into different sexes. Piko, however, has declared that he is a boy out of a desire to be the same as Hugh.
Though many other differences exist between plesiosauruses and their new above-water friends, great efforts are being made to heighten their mutual understanding of each other. Piko has been adopted by Ellen and Martin alongside Hugh as part of those efforts, and the new brothers have recently started helping take care of the sharks at the marine sanctuary.