The largest living species of turtle is the leatherback sea turtle (Dermochelys coriacea). Unlike other turtles, which have hard shells, leatherbacks have a leathery carapace that is flexible and streamlined for swimming long distances. Adult leatherbacks can weigh between 550 to 2,000 pounds and measure up to 7 feet in length. They inhabit oceans worldwide, primarily feeding on jellyfish. Leatherbacks are notable for their ability to maintain a body temperature warmer than the surrounding water, which aids their survival in colder waters. Conservation efforts are vital for this species, as they face threats from habitat loss, fishing bycatch, and climate change.