Leatherbacks are sometimes called the last of the dinosaurs because their ancient ancestors lived when the dinosaurs did. Their ability to swim long distances may be one of the reasons they survived whatever killed most of the dinosaurs 65 million years ago. In modern times, one leatherback swam from Indonesia to Oregon. It had traveled 12,774 miles in 647 days, the longest distance ever tracked for a marine animalThese sea turtles are also known for returning to the same nesting sites from which they hatched. Hatchling leatherbacks make a mad dash from the sand to the sea to avoid air and land predators. While gains have been made to improve the turtles' chances against commercial fishing techniques, humans have continued building on nesting beaches and polluting the oceans. Find out what other threats the leatherbacks face, and what you can do to help protect these endangered reptiles of the sea.