Green Sea Turtle
Green Sea Turtle Green Sea Turtle Green Sea Turtle Green Sea Turtle Calypso Video

Green Sea Turtle, Chelonia Mydas

The green sea turtle gets its name not from the color of its shell (which is typically brown, gray, black and yellow) but from the greenish shade of its fat.

A serrated beak helps these herbivores tear through vegetation. Their shells, which are lighter and more hydrodynamic than those of terrestrial turtles, allow them to glide easily through the water, while flippers enable them to swim long distances.

Male sea turtles spend their entire lives at sea, but females return to the same beaches they were born on, once every two years or so, to lay eggs.

Green Sea Turtle Facts

Did You Know?

Sea turtles are unable to pull their heads or appendages into their shells.


As juveniles, green sea turtles are carnivorous, feeding on jellies and other invertebrates. As adults they are strictly herbivores, feeding on sea grasses, algae and other vegetation.


With a shell length of 3.5 feet and weighing upward of 400 pounds, green sea turtles are second in size only to the behemoth leatherback sea turtle.


Green sea turtles are found worldwide in tropical and subtropical seas, along the coasts of continents and islands. They are known to nest in more than 80 countries.

Population Status

Globally, green sea turtle populations are in decline. In the U.S., certain populations are threatened or endangered. Many are killed unintentionally as bycatch or die following entanglement in discarded fishing gear or after ingesting marine debris, especially plastics.

In parts of their range, nesting is hindered by coastal development and other activities. After hatching at night, baby sea turtles find their way to the ocean by following the brightest horizon. Confused, many head toward the artificial lights of houses, hotels or other structures and never reach the water.

Some populations suffer from fibropapilloma. Turtles with this disease develop fleshy tumors on the skin and internal organs that can impair vision, feeding, breathing and other vital functions.


Raccoons, foxes, dogs, seabirds and ghost crabs prey upon turtle eggs. Juveniles are eaten by seabirds, crabs and carnivorous fish. Adults may be eaten by tiger sharks. Humans, however, pose the greatest threat due to harmful fishing practices, nesting beach destruction, pollution and turtle harvesting.

Humans, however, are the greatest threat to sea turtles. People harvest adults and eggs, disturb nesting beaches, pollute and fish in ways that are harmful to turtles.

Calypso's Story

The Aquarium’s green sea turtle was born, we estimate, in 1998. In 2000, this sea turtle was stranded in Long Island Sound and rescued by the Riverhead Foundation for Marine Research and Preservation.

Weighing just 6 pounds, the small turtle was cold stunned and had an infected left front flipper. The flipper was untreatable and was amputated. Almost two years later, and several pounds heavier, the turtle was donated to the National Aquarium. At the time, it was believed that the sea turtle could not be returned to the wild. After three months in quarantine, the turtle, nicknamed Calypso, was moved to the Wings in the Water exhibit (now Blacktip Reef). A decade later, Calypso weighs an impressive 500 pounds.

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A Note From the Caretaker

When visiting the Aquarium, you'll notice that our green sea turtle is missing a front flipper. Our turtle was rescued by the Riverhead Marine Foundation off Long Island, New York. It was cold-stunned, and its left front flipper was severely infected.

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