A turtle’s diet varies greatly depending on the environment in which it lives. Adult turtles typically eat aquatic plants; invertebrates such as insects, snails, and worms; and have been reported to occasionally eat dead marine animals. Several small freshwater species are carnivorous, eating small fish and a wide range of aquatic life.
Doesn’t say a thing about watermelon, though:
I wonder if now they’re going to come up to the house and demand the stuff.