The status of green turtle populations is difficult to determine because of our lack of knowledge about their life cycles. The number of nests deposited in Florida appears to be increasing, but we don't know whether this is due to an increase in the number of nests or because we have started to monitor nesting beaches more closely. Description The green sea turtle is the largest hard-shelled sea turtle. Adults of this species commonly reach 100 cm in carapace length and 150 kg in mass. The average size of a female nesting in Florida is 101.5 cm straight carapace length, with an average body mass of 136 kg.
Hatchlings are black on top and white underneath.
The plastron of Atlantic green turtles remains a yellowish white throughout life, but the carapace changes colour from black to various shades of gray, green, brown and black, forming swirls and irregular patterns on their shells. Green turtles grow slowly. In the southern Bahamas, green turtles grew from 30 to 75 cm in 17 years, and according to Bjorndal and Bolten, growth rate decreased with increasing carapace length. Growth rates measured in green turtles from Florida and Puerto Rico fall within the range of growth rates measured in the southern Bahamas. Based on growth rate studies of wild green turtles, the researchers Balazs, Frazer and Ehrhart estimate the age at sexual maturity range anywhere from 20 to 50 years.