Green turtle has a bigger type of build. The length of mature turtle’s shell is about 90~120 cm. It weight can be over 100 kg. It is named because the fat of its body is full of chlorophyll coming from its main food, seaweeds. It has a moderate temper, no teeth, and it can not shrink limbs and head into tortoise-shell like land turtles when it gets into scrapes, but it can get out of attacking from the natural enemy in the sea through its big build and nice swimming skill. General speaking, male turtle’s tail is longer than female’s, but it is hard to be recognized in unripe period. Besides climbing to lay eggs, they pass days in the ocean all their life. Green turtle distributes over the sea area in the tropics and the subtropical zone, and lays eggs on the beach at more than 25℃. They are very loyal to their habitats that as soon as those places are confirmed, they will return to the hatchery or habitat whatever how far they should swim. The green turtles reproduce in Wangan Township of Penghu which mating season is in every April and May, and nesting season is from May, June to the middle and the end of October. They incubate for about 50 days, and the sex of sea turtle depends on sand temperature in the end of incubation period. According to studies, when the temperature is higher than 30℃, most incubated eggs are female turtles; when the temperature is lower than 28℃, most incubated eggs are male turtles; only between 28℃ and 30℃, the ratio of young green turtle is 1:1. Young green turtles have many natural enemies so that their death rate is very high. According to estimations, among every thousand young turtles, there is only one young turtle that can grow up. Mature female turtles return to their birthplaces to lay eggs every two to four or five years on average. Migration for laying would be a stable migration style of hatchery ←──→foraging place with distance that can be as far as more than thousands of kilometers.