At least 45 years to reach sexual maturity
Green turtles are rare in temperate waters, but are distributed widely through the tropics near continental coasts and around islands.
BreedingThe age of sexual maturity is uncertain: current estimates range from 45 to 50 years of age. Females migrate huge distances between feeding grounds and nesting areas, but tend to follow coastlines rather than cross open water.
There are exceptions, such as the green turtle nesting population of Ascension Island that migrates to feeding grounds off Brazil, and foraging turtles in Fiji that come from nesting beaches in Australia and Samoa, amongst other countries in the region. An individual female nests approximately every three years, and lays between one to six clutches of between 70 and 110 eggs, depending on the population. The incubation period lasts 50 to 70 days.
Diet
Adult green turtles are the only truly herbivorous marine turtles. They feed mainly on seagrasses or algae, mostly in the tropics and subtropics, but juveniles are assumed to be omnivorous to allow for their high growth rates. There is probably a gradual transition to herbivory, once the turtle is large enough to escape predators.