Sea turtles are classified in the Class Reptilia, Subclass Anapsida and Order Testudines. There are seven recognized species of sea turtles, six of which (the hawksbill, green, flatback, loggerhead, Kemp's ridley and olive ridley turtles) are in the Family Cheloniidae, with only one (the leatherback) in the Family Dermochelyidae. All seven species of sea turtles are listed under the Endangered Species Act.
The leatherback is the largest sea turtle and can reach lengths over 6 feet and weights over 2,000 pounds. These animals are deep divers, and have the ability to dive to over 3,000 feet. Leatherback turtles nest on tropical beaches, but can migrate as far north as Canada during the rest of the year. This turtle’s shell consists of a single piece with 5 ridges, and is distinctive from other turtles who have plated shells.
The green turtle is large, with a carapace up to 3 feet long. Green turtles weigh up to 350 pounds and their carapace can be many colors, including shades of black, gray, green, brown or yellow. Adult green turtles are the only herbivorous sea turtles. When young, they are carnivorous, but as adults they eat seaweeds and seagrass. They are found in tropical and sub-tropical waters around the world.
The hawksbill turtle grows to lengths of 3.5 feet long and weights of 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 were hunted nearly to extinction for their shells. Hawksbill turtles live in tropical waters and feed on sponges.
Olive ridley turtles 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 are found in tropical regions around the world. They eat mostly invertebrates such as crabs, shrimp, rock lobsters, jellyfish, and tunicates, although some eat primarily algae. When nesting, females come to shore in colonies of up to a thousand turtles and have mass nesting aggregations (arribadas) on the coasts of Central America and East India.