Terrestrial and freshwater turtles do not occur in Alaska, but four species of sea turtles have been documented in Alaska's Gulf Coast waters. These are the leatherback sea turtle, the green sea turtle, the olive ridley sea turtle and the loggerhead sea turtle.
The Leatherback sea turtle is the world's largest turtle. Since 1960, there have been 19 documented sightings of these impressive reptiles. There have been 15 reports of green sea turtles. Sightings of the other two sea turtle species can be counted on one hand, just three sightings of olive ridleys and two sightings of loggerheads.
Leatherbacks can be eight feet long and weigh 1,500 pounds, but most are about half that size and weight. Green sea turtles average about three feet in length and weigh about 200 pounds.
Leatherback sea turtles feed almost exclusively on jellyfish. Leatherbacks have a mammal-like ability to maintain a high body temperature, about 80Â° F, independent of the temperature of the surrounding water. This may account for their occurrence in cold northern waters where jellyfish are seasonally abundant.
Marine turtles may migrate thousands of miles between their nesting and feeding grounds, and probably reach Alaska by way of the warm Japan Current and the North Pacific Current, which flow toward Southeast Alaska and then arc northwest across the Gulf of Alaska and then southwestward along the Aleutian chain.
The leatherback sea turtle is endangered throughout its range. All marine turtles are protected by the federal government.