Sea turtles’ nests monitoring
Sea turtles’ nests monitoring provide many information on tracks, nests and sea turtles populations.
These data can be used as precious tools to improve conservation programs for these endangered species.
Which turtles lay eggs in French Polynesia, and when?
Five species of turtles (out of seven existing in the world) live in Polynesian waters.
The Leatherback, the Olive Ridley turtle and the Loggerhead are rarely seen. The Hawksbill turtle, who feeds in Polynesian waters, is frequently seen. However, only one species lay eggs on Polynesian beaches: the Green Turtle.
During the egg-laying season (from the end of September to the beginning of April), green turtles regularly come to lay eggs: between 3 to 5 times, with intervals of 12-15 days.
They dig a nest at the higher end of the beach (where the vegetation starts, or even sometimes under the vegetation), et lay on average a hundred eggs per nest.
Green turtles lay egges at night, in order to avoid deshydratation due to the intense heat during daytime.
However, each track does not necessarily leads to a nest, as it happens that the female comes out on the beach and goes back in the water without laying eggs («false nests»).
Where is the monitoring done?
At present, sea turtles’ nests monitoring are done regularly or punctually in French polynesia on several islands: Bora Bora, Maiao, Maupiti, Tupai and Tetiaroa in the Leeward Islands, and Tikehau and Mataiva in the Tuamotu islands.
Since 2004, te mana o te moana has implemented a program for the monitoring of turtle’s nests on Tetiaroa, a well preserved and undisturbed atoll nearby Tahiti, consisting of 12 motu (small sandy islands forming the atoll) where green turtles are regularly seen during the nesting season.
Te mana o te moana tries to be present on the atoll during the entire nesting season. Teams of volunteers, supervised by marine biologists from te mana o te moana, take turns on the island to ensure the continuity of the observations (see below: who does the survey?)
How is the survey done?
Surveys can be done during day time, or at night. Terrestrial observations consist in walking along the beach and looking for signs testifying that a turtle has come out of the water to lay eggs (tracks on the beach, sandy areas being searched or excavated, nests, etc.).
All observations are measured (track’s width, direction, size of the nest, distance to the shore, etc.). In addition, a detailed topographical description of the surroundings is made, and the presence of potentiel predators threatening the hatchlings is also accurately described. The nest is marked and its GPS position located.
Who does the survey?
Te mana o te moana conducts regular monitoring campaigns on Tetiaroa since 2004. In order to conduct a continuous monitoring during the nesting season, volunteers and members from Te mana o te moana camp on-site.
Eco-volunteers from Planète Urgence
Planete Urgence is a French law non-profit and non-governmental organization of public interest. Found in July 2000, it aims at supporting local sustainable development and environmental projects in the South.
Te mana o te moana established a partnership with Planete Urgences non-governmental organization for 3 years from 2008 to 2011. During January and February (peak period of the nesting season), teams of ecovolunteers took part in the the on-field beach nesting monitoring mission of te mana o te moana on Tetiaroa atoll.
Who else?
Any person (see conditions below) who wishes to dedicate some spare time to contribute to the scientific study of sea turtles can take part to the survey.
The conditions are :
- to be available at least 2 half-days every month
- to have rapid and easy access to egg-laying beaches
- to be in good shape
- to have a GPS, a tape measure and a notepad.
Sea Turtles’ nests MONITORING PROTOCOL – June 2011 (in French)
Sea Turtles Observatory
The Sea turtle Observatory was established in 2011. To face the conservation issues of these endangered species, the observatory constitutes a particularly important participative and awareness management tool and has a local and international component.
For more information, or if you have any information to communicate about sea turtles, or to help in the collect of information, please contact :
Sea Turtles Observatory in French Polynesia
Tél: (689) 56 40 11 ou (689) 71 53 44
temanaotemoana@mail.pf
