Snapping Turtles

• The snapping turtle and the alligator snapper, the two species of snapping turtles in North America that belong to the Chelydridae family, eat whatever they can "fit" into their mouths, notes California Herps. Snappers forage for food when young, but typically ambush when older, eating carrion, fish, snails, snakes, small mammals, birds, slugs, salamanders, other turtles and plant matter.
  
  

Mud and Musk Turtles

• The mud and musk turtles, belonging to the Kinosternidae family, are omnivores. These turtles spend most of their time in the water, but they will venture onto land. Mud and musk turtles eat snails, carrion, aquatic invertebrates, tadpoles and some plants, states the Arizona Game and Fish Department. Certain species focus their diets on one major food source, according to the "National Audubon Society Field Guide to Reptiles and Amphibians." For example, the Sonora mud turtle of the Southwest consumes a diet almost entirely of snails.
  
  

Marsh, Box and Pond Turtles

• The Emydidae family of turtles is the largest, with some 26 types of these turtles -- including pond and box turtles -- native to North America. In many instances, these species are carnivores when young, but convert to a mostly vegetative diet as they mature. This family includes the painted turtle, a species with a large distribution across the continent. Painted turtles enjoy a diet of bugs, aquatic plants, carrion, mussels, snails and crayfish, reports the Connecticut Department of Energy and Environmental Protection.
  
  

Tortoises

• Tortoises have mostly vegetarian diets.Jupiterimages/Photos.com/Getty Images
  
  Tortoises living in the United States are part of the Testudinidae family, with all three species being gopher tortoises of the Gopherus genus. These turtles dwell on land, digging burrows to live in, and eat vegetation. Although they occasionally scavenge a carcass if the opportunity arises, gopher tortoises usually stick to a menu of grasses, cacti, fruits and berries, depending upon the species and their habitat.
  
  

Sea Turtles

• The Chelonidae and the Dermochelyidae families encompass the North American sea turtles, which venture onto land only to lay their eggs. Their diets differ among species. The loggerhead turtle has jaws designed to crush food and grind it, so their diets include jellyfish, clams, crabs and shrimp, notes Sea World. The leatherback sea turtle, with its jaws resembling scissors, targets mostly soft creatures such as jellyfish. The hawksbill sea turtle, with its beak-like jaws, concentrates its efforts on finding invertebrates like sponges and squids.