Diamondback terrapin nests are depredated by skunks, raccoons, and foxes. Upon emerging from the nest, young hatchlings are often eaten by gulls, crows, and black-crowned night-herons. Although the hatchlings are less vulnerable to predation when in water, they can still be preyed on by herons and predatory fish.
In the wild they mostly feed on clams, shrimp, crabs, snails, and small fish. They have been known to eat some vegetation but they are primarily carnivores.