The Status and Conservation of Sea Turtles in Kenya. Seasonal fluctuations in sand temperature: effects on the incubation period and mortality of loggerhead sea turtle (Caretta caretta) pre-emergent hatchlings in Minabe, Japan. Matsuzawa Y, Sato K, Sakamoto W and Bjorndal KA 2002.Citizen science surveys elucidate key foraging and nesting habitat for two endangered marine turtle species within the Republic of Maldives. Hudgins JA, Hudgins EJ, Ali K and Mancini A 2017.Green turtle hatchlings in the Maldives emerge from their nest after between 49 and 62 days. Younger female turtles may follow older, experienced nesting turtles from their feeding grounds to the breeding site.Beach characteristics used may include smell, low-frequency sound, magnetic fields, the characteristics of seasonal offshore currents and celestial cues. It is believed that hatchlings imprint the unique qualities of their natal beach while still in the nest and/or during their trip from the nest to the sea.Whether they actually use this ability to navigate is the next idea being investigated. Early experiments seem to show that sea turtles have the ability to detect magnetic fields. Using these two characteristics, a sea turtle may be able to determine its latitude and longitude, enabling it to navigate virtually anywhere. They can detect both the angle and intensity of the earth’s magnetic field.There are several theories as to how sea turtles are able to return to their birthplace to nest, but none have yet been proven. Interestingly, the flatback is more closely related to loggerheads, hawksbills and ridleys than green turtles.Īlthough some sea turtles may return to the beach where they were born to nest (natal homing), equally many will nest on a different beach in the same region where they were born. It later turned out that the original bones used to describe the species where actually a mix of flatback and green turtle skeletons! After many debates and confusion, it was given its own genus Natator and later DNA analyses confirmed the status of the species. The flatback turtle was first described by Samuel Garman in 1880 as a direct sister species to the green turtle, and named Chelonia depressa, where the species name depressa refers to the flat depressed shell. This overall compressed carapace, with the outer margins pointing upwards, gives them their name flatback. The species has the same scute and scale pattern as green turtles on carapace and shell, but it is distinctly flatter. Adult nesting females measure 86-97 cm in curved carapace length and weigh up to 67.4 kg. The flatback turtle ( Natator depressus) is a comparatively pale turtle with a very light olive green to grey carapace and a cream-colored plastron.
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