Green turtles are so named because of the greenish color of their subdermal fat.

Green turtles are so named because of the greenish color of their subdermal fat. Green sea turtles are black at hatching, but then change color over the course of thier lives as the turtles mature.

The coloration of juvenile green sea turtles has been found to be fairly uniform: the carapace and top of head light brown; the side of the head and dorsal surface of the flippers dark brown; the beak brown; the plastron, throat, and ventral surface of the flippers entirely creamish white, except for a few light brown scales distally located on the flippers.

Larger juvenile turtles occasionally have yellow or black streaks radiating peripherally on the carapace shields, the general color pattern of the entire dorsal surface becoming darker. All interscute areas on the carapace and interscale areas on the head and flippers are well defined and creamish-white.

Adult green turtle coloration, in contrast to that of the juveniles, shows considerable variation: the background coloration of the carapace and top of head ranges from dark brown to light green, generously infused with combinations of yellow, brown, and black; beak brown; pastron, throat, and ventral surface of the flippers creamish, except for scattered dark centered scales on the flippers.

Sources: (Hersh, 2016; Witzel, 1982)
Image: Jeremy Bishop