The preferred food of green sea turtles changes as the ygrow. Newborn turtles live in the open ocean and eat meat, feeding on fish eggs, plankton, mollusks, jellyfish, worms and crustaceans. When they grow older, they consume more and more vegetation, living in meadows of seagrass. Their diet of plants is what turns their body fat green, which is where their name comes from.
Adult green sea turtles have few predators, other than large sharks (like tiger sharks) and humans. Young turtles face much more danger from predation, with crabs and seabirds at the top of the list. These turtles take up to 20 years to reach maturity, and can live as long as 80 years or more, though as few as 1% of turtle hatchlings may reach maturity.
Other than laying eggs and hatching, the turtle spends its entire life at sea. While it stays below the water most of the time, it must lift its head above water to breathe air periodically. Green sea turtles usually hold their breath for around five minutes while they are active, but they can hold their breath much longer when they sleep – up to several hours.