|While diving or whale watching, it is possible to cross paths with a few turtles. We often see them breathing on the surface and it is sometimes possible to approach them by swimming if you know how to be discreet. To do this, just follow the advice of your guide|
Sea turtles are one of the oldest groups of animals on the planet. Although they are perfectly adapted physically and physiologically to live at sea, they still depend on the terrestrial environment during one of the decisive stages of their life cycle, the spawning and incubation of eggs which takes place on the beaches.
Sea turtles spend most of their lives at sea where they feed and mate. They move between their feeding grounds and their spawning grounds. Mating takes place at sea near nesting sites or during migrations. The females then lay between 70 and 200 eggs depending on the species, approximately on the area of their birth.
After an incubation period of about 2 months, the hatchlings emerge from the sand and immediately begin to crawl out to sea and then swim to deeper waters where predators are scarce. The life of small turtles is risky: on average only one in a thousand will reach adulthood.
Sea turtles feed mainly on marine plants, jellyfish, ascidians, sponges, soft coral, molluscs, crabs, squid or fish, depending on the species. It seems that some species can eat any type of food available in abundance. Others, such as the green sea turtle, chelonia mydas, are almost exclusively carnivorous in the juvenile stage and then change their diet once they reach adulthood to mainly consume marine plants and algae.
Only seven species of sea turtles currently inhabit the world's oceans. Loggerhead turtle (careta careta), green turtle (chelonia mydas), hawksbill turtle (eretmochelys imbricata), Kemp's turtle ( lepidochelys Kempii), olive ridley sea turtle (lepidochelys olivacea), flatback sea turtle (natator depressus) and leatherback sea turtle (dermochelys coriacea).
If in French Polynesia 5 species of sea turtles are represented (green turtle, hawksbill turtle, loggerhead turtle, olive ridley turtle, leatherback turtle), 2 are more easily observable, the green turtle and the hawksbill turtle. However, all of them are threatened.
|GREEN TURTLE chelonia mydas|
The green turtle is the only species to lay eggs in Polynesia. It stands out well thanks to its round and smooth shell, and its rounded beak. It has 2 prefrontal scales and 4 costal scales. Its name comes from the color of its fat which is green. Its carapace measures on average 110 cm. Its average weight is around 120 kg. Some specimens can weigh up to 400 kg.
The diet varies with the age of the turtle. It is first carnivorous in its youth, its food then consists of small invertebrates, fish fry, fish eggs, jellyfish and zooplankton. It then becomes herbivorous, it grazes the underwater meadows. Unfortunately, the green turtle is still poached for its flesh.It is a globally endangered species!
|HAWSBRIDGED TURTLE eretmochelys imbricata|
The hawksbill turtle is recognizable by its slender head and its pointed beak like that of a raptor, hence its English name "hawksbill turtle". The scales of its shell are superimposed on each other. It has 4 prefrontal scales and 4 costal scales. The hawksbill turtle is the only one to have a serrated carapace on its terminal part, the other turtles generally having serrated carapaces in a rounded way. Its carapace has a very striking color pattern of yellow, brown and black spots. The color of their belly ranges from pale yellow to white, sometimes showing black spots.
Its average height is 85 cm for an average weight of 60 to 70 Kg. It usually frequents coral reefs feeding on sponges, corals and other marine invertebrates. It is a species classified as critically endangered worldwide! In French Polynesia, hawksbill turtles very rarely lay eggs.