Changing seawater temperature, sand, air and weather phenomenon due to climate change on nesting survival, abundance and size, their impact on ratio male/female and prediction for future of the marine turtles in Colima state.
Supervisors: Mary Cruz Rivera, Fabien Leprieur (Tortugario, Cuyutlan)
During those almost 5 months, studies have been done on marine turtles sp by observing their general behavior in order to understand how they are impacted by climate change in Colima state, Mexico. In the ecological center of Cuyutlan, 3 researchers were working in the laboratory. Their mission was to measure, count and insure the health of marine turtles sp. However, among all of them, only a few have a PhD which is not something common in Mexico. As a result, there was a loss of precision in data measurement combined with the small amount of measurement tools available. In Mexico, I contacted a marine biologist teacher and a researcher I knew to help me with my master thesis. With the help of Mary Cruz Rivera Rodriguez, responsible for the Tortugario and Fabien Leprieur, marine biologist in the University of Montpellier, we were working together in order to collect data and to find possible answers to my subject questions. Two species were present in the center : Lepidochelys olivacea and Chelonia mydas. To complete the development of the MSc Project, the access to previous data recorded for the last 25 years were shared to extrapolate and establish a potential future scenario for the evolution of marine turtles species in the Pacific Mexican coast. By computing this with climate change parameters found online and also measurements like the male/female ratio of newborns, a decrease in the general abundance of turtles have been projected. The ecological center is in charge of the preservation and the education but also the protection of marine turtles sp. Strategic learning is made by taking eggs from the beach, having a look at the eggs development and protecting them from possible predators and poachers. This master thesis project comes as a complement of studies already realized concerning the threats of all marine turtles species. Indeed, since almost 25 years, the number of nests, eggs and newborns has been constantly decreasing. The conservation established by the center helps to prevent a part but not the entire problem. For example, nowadays, almost no leatherback nests are found on the Pacific coast of Mexico. Through analyses of several climate change parameters, we attempt to determine if marine turtle species are going to disappear from this region or from the world and which specific amount of male is necessary before reaching the non return point. In addition to databases concerning sea surface temperature, sand moisture, air temperature, humidity, precipitation, it was possible to establish a connection between the decrease of survival and the ratio proportion.

Keywords: climate change, marine turtles sp, number of eggs, number of nests, number of newborns, future, evolution, male/female ratio.