Tennyson is a bespectacled turtle who lives in Kermit's Swamp. He is invited to the good-bye party that Kermit throws at the end of the 1992 storybook Kermit, Save the Swamp!

Although he had been looking forward to the Swamp World shopping mall and amusement park, he has second thoughts when Kermit points out that the pond will be drained, as he not only swims there but also loves to chew on the swamp grass. Eventually, Tennyson joins with the other swamp inhabitants in the decision not to sell their land to developers.