From March to November, the beaches of Saint-Martin are fortunate to welcome the eggs of three of the seven species of sea turtles existing in the world: the green turtle, the nested and the luteIn the early morning, sometimes only a few traces of their passage remain. Learn to recognize them and report them to the Saint-Martin nature reserve allows better understand their reproduction and especially contribute to their protection.
“Wherever there is sand in Saint-Martin, there is potentially a nesting site.” Aude Berger, head of sea turtle monitoring at the Nature Reserveknows by heart the clues left by these discreet visitors. But it's impossible for the local branch to patrol all the beaches on the French side every day: The work of eco-volunteers is therefore essential to them.
Learning to read the sand
Observing the tracks is first and foremost a matter of patience and walking! To follow the egg-laying, you have to cover a beach from end to end, preferably at early morning, before the walkers pass by, and transmit these observations to the reserve, even when there is nothing there: The absence of information also constitutes a scientific fact..
The most visible sign is a large basin dug in the sand, which does not necessarily indicate egg-laying.There may be several attempts before egg-laying occurs. “explains Aude Berger. A tortoise may start digging and then leave, disturbed by light, a smell, a presence, or conditions that are unsuitable. And if, after several days, it hasn't managed to lay its eggs in the sand, She lays her eggs in the sea..
Other traces are left on the beaches: those of fins in the sandwhich allow the species to be identified. green turtle advances with both fins simultaneously and leaves two parallel grooves ; the nested uses them alternately and draws a slightly zigzag track ; The luteShe, however, leaves a similar track to that of the green turtle, but much widerOften, only Aude Berger's trained eye can definitively determine the species and even the trajectory (uphill or downhill) of a track. That's why the main instruction is to send the photos to the specialist traces that we find, with a GPS point.
Beneath the sand, future generations
A clutch of eggs averages 100 to 150 eggs which remain buried about two months before the hatchlings emerge. The temperature of the nest influences their sex: the Cool temperatures favor the males., the warmer, the femalesYet another consequence of global warming: the ever-increasing temperatures unbalance the populations and favor an increasing proportion of females, threatening the reproduction of the species.
When an outbreak occurs, the only thing to do is to do not try to "help" to reach the sea. It is this journey to the ocean that allows them to activate their muscles and "record" the beach on which they were born and where they will return to lay their eggs. On the other hand, we can Keep dogs, birds, and crabs away baby turtles, clearing a path for them through the sargassum seaweed and above all, warn the reserve.
Among 82 traces of turtles recorded this year, only 12% gave rise to a suspected egg-layingA nest is therefore particularly rare and must also face very real dangers: campfires on the sand and domestic animals, both prohibited on the beaches of the reserve, constitute real dangers for the eggs, in addition to their natural predators (rat, mongoose and iguana).
And if, while strolling along a beach, you're lucky enough to spot a turtle, the reserve team reminds everyone that it's essential to keep a safe distance and avoid disturbing it: no lights, no noise, and no attempts to approach. Protecting sea turtles doesn't require expertise; you simply need to learn how to observe. _DR
To join the eco-volunteers of the Saint-Martin nature reserve: https://urls.fr/aubrT2
