Cool sand indicates that it is night or an overcast day. The hatchlings then emerge from the nest, thereby avoiding the sun's heat and perhaps predatory birds. O nce out of the nest, the hatchlings race to the water and swim constantly for the next 36 to 48 hours. They are then carried by currents to favorable areas in the open ocean, where they grow for several years until they join adult and juvenile turtles at the coastal feeding grounds. While in the open ocean, young green turtles are probably carnivorous and feed on invertebrates such as jellyfish.
Some hatchlings never reach the oceans and are snatched up by hungry crabs.
Hatchlings may also be disoriented or impeded by obstacles and die from the suns heat. Once in the ocean, sharks and other carnivorous fish eat hatchlings. Tiger sharks regularly feed on all sizes of green turtles. T he life span of sea turtles is unknown. Hawaiian green turtles seem to grow very slowly in the wild and may take 40 to 50 years to reach sexual maturity.