How many species of sea turtles are there?

There are seven living species of sea turtle. They are the flatback, green, hawksbill, leatherback, loggerhead, Kemp’s ridley, and olive ridley turtles.

Sea turtles belong to the order Testudines and are divided between two living lineages. Six species have hard shells and belong to the family Cheloniidae. The leatherback is the sole living member of the family Dermochelyidae and has a flexible, leathery shell rather than a conventional bony carapace.

The seven species occupy oceans and coastal habitats worldwide, although their ranges and nesting beaches differ. Most migrate long distances between feeding grounds and the beaches where they reproduce. Hatchlings typically head toward the sea soon after emerging from nests, using environmental cues such as light and the slope of the beach.

People sometimes count sea turtles incorrectly by including extinct species, regional populations, or subspecies. Conservation status is another important part of the story: five of the seven living species are listed as threatened globally, while the flatback and green turtle have different assessments depending on the population and classification used.