Number of female green sea turtle (<em x-id="3">Chelonia mydas</em>) coming ashore to lay eggs


Flagship species, keystone species, conservative species, and endangered species have important ecological status and should be monitored and protected as a priority.



Indicator Details


Abundance trends of selected taxa

PSBR model type

State (S)

Corresponding targets

Aichi Biodiversity Targets

Target 12 By 2020 the extinction of known threatened species has been prevented and their conservation status, particularly of those most in decline, has been improved and sustained.


Green sea turtles (Chelonia mydas) belong to the Cheloniidae family. They are medium/large-sized sea turtles and migrate to the sea area near their birthplace to mate during the breeding season. When the eggs mature, the female turtle lays her eggs on the beach where the temperature is higher than 25℃. The average hatching period is 45-55 days, and the success rate is about 70%. Currently, six beaches in Taiwan where they lay eggs have been protected as wildlife sanctuaries. The research team from National Taiwan Ocean University collected 24 and 19 years of green sea turtle's reproductive ecology data on Wang-an Island in Penghu County and Orchid Island in Taitung County, respectively. According to the corresponding 19-year data from both islands, they found that the difference (between the two islands) in the changes in the number of spawning female turtles may relate to fishery hunting on the high seas (if continuous monitoring has been done). Other possible causes and global climate changes are further studied to determine whether they affect the spawning population. These results are of great significance to academic research and the establishment of relevant government policies.

Definition and Calculation

During the peak of the spawning seasons (June-September) each year, researcher will go to each spawning place and stay for long-term surveys on the islands. In addition to counting the number of female turtles coming ashore, they also record information related to the appearance and quality of the eggs and newly hatched turtles, and use satellite transmitters to track the migratory patterns of female turtles and the location of foraging areas.


No data currently available



Data Management Authorities

Forestry Bureau, Council of Agriculture

Data Source / URL


Data Development Status


Investigation Year