Science, Tech, Math › Animals & Nature 7 Species of Sea Turtles These animals have been around for millions of years Share Flipboard Email Print Animals & Nature Marine Life Marine Life Profiles Marine Habitat Profiles Sharks Key Terms Amphibians Birds Habitat Profiles Mammals Reptiles Wildlife Conservation Insects Forestry Dinosaurs Evolution View More By Jennifer Kennedy Marine Science Expert M.S., Resource Administration and Management, University of New Hampshire B.S., Natural Resources, Cornell University Jennifer Kennedy, M.S., is an environmental educator specializing in marine life. She serves as the executive director of the Blue Ocean Society for Marine Conservation. our editorial process Jennifer Kennedy Updated August 12, 2019 Sea turtles are charismatic animals that have been around for millions of years. There is some debate on the number of sea turtle species, although seven have traditionally been recognized. Six of the species are classified in the Family Cheloniidae. This family includes the hawksbill, green, flatback, loggerhead, Kemp's ridley, and olive ridley turtles. These all look fairly similar when compared to the seventh species, the leatherback. The leatherback looks very different from the other species and is the only sea turtle species in its own family, Dermochelyidae. All seven species of sea turtles are listed under the Endangered Species Act. 01 of 07 Leatherback Turtle C. Allan Morgan/Photolibrary/Getty Images The leatherback turtle (Dermochelys coriacea) is the largest sea turtle. These gigantic reptiles can reach lengths of over 6 feet and weights of over 2,000 pounds. Leatherbacks look very different from other sea turtles. Their shell consists of a single piece with five ridges, which is distinctive from other turtles who have plated shells. Their skin is dark and is covered with white or pink spots. Leatherbacks are deep divers with the ability to dive to over 3,000 feet. They feed on jellyfish, salps, crustaceans, squid, and urchins. This species nests on tropical beaches, but can migrate as far north as Canada during the rest of the year. 02 of 07 Green Turtle Westend61 - Gerald Nowak/Brand X Pictures/Getty Images The green turtle (Chelonia mydas) is large, with a carapace of up to 3 feet long. Green turtles weigh up to 350 pounds. Their carapace can include shades of black, gray, green, brown, or yellow. Scutes may contain a beautiful pigmentation that looks like a sun's rays. Adult green turtles are the only herbivorous sea turtles. When young, they are carnivorous, but as adults, they eat seaweeds and seagrass. This diet gives their fat a green tinge, which is how the turtle got its name. Green turtles live in tropical and subtropical waters around the world. There is some debate over green turtle classification. Some scientists classify the green turtle into two species, the green turtle and the black sea turtle or Pacific green sea turtle. The black sea turtle may also be considered a subspecies of the green turtle. This turtle is darker in color and has a smaller head than the green turtle. 03 of 07 Loggerhead Turtles Upendra Kanda / Moment / Getty Images Loggerhead turtles (Caretta caretta) are a reddish-brown turtle with a very large head. They are the most common turtle that nests in Florida. Loggerhead turtles can be 3.5 feet long and weigh up to 400 pounds. They feed on crabs, mollusks, and jellyfish. Loggerheads live in temperate and tropical waters throughout the Atlantic, Pacific, and Indian Oceans. 04 of 07 Hawksbill Turtle Danita Delimont/Gallo Images/Getty Images The hawksbill turtle (Eretmochelys imbricate) grows to lengths of 3 1/2 feet long and can weigh up to 180 pounds. Hawksbill turtles were named for the shape of their beak, which looks similar to the beak of a raptor. These turtles have a beautiful tortoiseshell pattern on their carapace and have been hunted nearly to extinction for their shells. Hawksbill turtles feed on sponges and have an amazing ability to digest the needle-like skeleton of these animals. Hawksbill turtles live in tropical and subtropical waters in the Atlantic, Pacific, and Indian Oceans. They can be found among reefs, rocky areas, mangrove swamps, lagoons, and estuaries. 05 of 07 Kemp's Ridley Turtle YURI CORTEZ/AFP Creative/Getty Images At 30 inches long and weighing up to 100 pounds, the Kemp’s ridley (Lepidochelys kempii) is the smallest sea turtle. This species is named after Richard Kemp, the fisherman who first described them in 1906. Kemp's ridley turtles prefer to eat benthic organisms such as crabs. They are coastal turtles and found in temperate to subtropical waters in the western Atlantic and Gulf of Mexico. Kemp's ridleys are most often found in habitats with sandy or muddy bottoms, where it is easy to find prey. They are famous for nesting in huge groups called arribadas. 06 of 07 Olive Ridley Turtle Gerard Soury/Oxford Scientific/Getty Image Olive ridley turtles (Lepidochelys olivacea) are named for—you guessed it—their olive-colored shell. Like the Kemp’s ridley, they are small and weigh less than 100 pounds. They eat mostly invertebrates such as crabs, shrimp, rock lobsters, jellyfish, and tunicates, although some primarily eat algae. They are found in tropical regions around the world. Like Kemp's ridley turtles, during nesting, olive ridley females come to shore in colonies of up to a thousand turtles, with mass nesting aggregations called arribadas. These occur on the coasts of Central America and India. 07 of 07 Flatback Turtle Auscape/UIG/Universal Images Group/Getty Images Flatback turtles (Natator depressus) are named for their flattened carapace, which is olive-gray in color. This is the only sea turtle species not found in the United States. Flatback turtles eat squid, sea cucumbers, soft corals, and mollusks. They are found only in the coastal waters of Australia.