The olive ridley sea turtle (or the Pacific ridley sea turtle) is found primarily in tropical Pacific and Indian Ocean waters, though it has been spotted in the Atlantic Ocean as well. An adult's carapace only measures 60 to 70 cm long, and the turtles rarely weigh more than 50 kg (110 lb), with males weighing considerably less. Hatchlings usually weigh between 12 and 23 g.The carapace is heart-shaped, with four pairs of pore-bearing inframarginal scutes on the bridge, two pairs of prefrontals, and up to 9 lateral scutes per side. The turtles are unique in that they can have variable and asymmetrical lateral scutes on each side. They are also remarkable for their synchronized nesting en mass (arribadas), after which females return to the same beach from where they hatched to lay their eggs, sometimes over 1000 km from the mating beach. The arribadas itself is the greatest single cause of egg loss, because the density of nesting females is so high that previously laid nests are inadvertently dug up and destroyed; for example, in Playa Nancite, Costa Rica, only 0.2% of the 11.5 million eggs produced in a single arribada successfully hatched. Females can lay up to three clutches per season, but most will only lay one or two clutches. Mean clutch sizes vary but decrease with each nesting attempt; average sizes are in the low 100s. The turtle was first designated "Testudo mydas minor" but was renamed "Chelonian olivacea, Eschscholtz" by the French coleopterist Pierre François Marie Auguste Dejean after Johann Friedrich Eschscholtz's death; he was a German physician, botanist, zoologist and entomologist from Dorpat, Livonia, who was part of Otto von Kotzebue's 1815-1818 and 1823-1826 Russian circumnavigational expeditions, one of the first and most important scientists in the exploration of the Pacific, Alaska, and California. Kotzebue named one of the Marshall Islands "Eschscholtz Atoll," but in 1946 it was renamed Bikini Atoll and became the site of notorious American atomic bomb tests. (The standard author abbreviation "Eschsch." is used in botanical citations.) In 1942, standard rules of nomenclature were applied, and the turtle became Lepidochelys olivacea Fitzinger. Lepidochelys is the only genus of sea turtles with more than one extant species: L. olivacea and the closely related L. kempii. The genus name is derived from the Greek "lepidos" (scale) and "chelys" (turtle); olive is the carapace color, but "ridley" is a mystery.
The olive ridley sea turtle (or the Pacific ridley sea turtle) is found primarily in tropical Pacific and Indian Ocean waters, though it has been spotted in the Atlantic Ocean as well. An adult's carapace only measures 60 to 70 cm long, and the turtles rarely weigh more than 50 kg (110 lb), with males weighing considerably less. Hatchlings usually weigh between 12 and 23 g.The carapace is heart-shaped, with four pairs of pore-bearing inframarginal scutes on the bridge, two pairs of prefrontals, and up to 9 lateral scutes per side. The turtles are unique in that they can have variable and asymmetrical lateral scutes on each side. They are also remarkable for their synchronized nesting en mass (arribadas), after which females return to the same beach from where they hatched to lay their eggs, sometimes over 1000 km from the mating beach. The arribadas itself is the greatest single cause of egg loss, because the density of nesting females is so high that previously laid nests are inadvertently dug up and destroyed; for example, in Playa Nancite, Costa Rica, only 0.2% of the 11.5 million eggs produced in a single arribada successfully hatched. Females can lay up to three clutches per season, but most will only lay one or two clutches. Mean clutch sizes vary but decrease with each nesting attempt; average sizes are in the low 100s. The turtle was first designated "Testudo mydas minor" but was renamed "Chelonian olivacea, Eschscholtz" by the French coleopterist Pierre François Marie Auguste Dejean after Johann Friedrich Eschscholtz's death; he was a German physician, botanist, zoologist and entomologist from Dorpat, Livonia, who was part of Otto von Kotzebue's 1815-1818 and 1823-1826 Russian circumnavigational expeditions, one of the first and most important scientists in the exploration of the Pacific, Alaska, and California. Kotzebue named one of the Marshall Islands "Eschscholtz Atoll," but in 1946 it was renamed Bikini Atoll and became the site of notorious American atomic bomb tests. (The standard author abbreviation "Eschsch." is used in botanical citations.) In 1942, standard rules of nomenclature were applied, and the turtle became Lepidochelys olivacea Fitzinger. Lepidochelys is the only genus of sea turtles with more than one extant species: L. olivacea and the closely related L. kempii. The genus name is derived from the Greek "lepidos" (scale) and "chelys" (turtle); olive is the carapace color, but "ridley" is a mystery.
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