Duckleberry Swim is one of Rubber Duckie's duckie friends who comes to visit in the 2002 book Look and Find Elmo. Duckleberry wears a tattered straw hat and cheerfully steers his raft through the bubbles in Ernie's bathtub.

Rubber Duckie's other duckie friends include Lucky Duckie and Grubby Duckie.

Duckleberry's name is a reference to Huckleberry Finn, who appeared in Mark Twain's The Adventures of Tom Sawyer and Adventures of Huckleberry Finn.