Chelonia mydas, commonly known as the green sea turtle or green turtle, is a large sea turtle belonging to the family Cheloniidae. It is the only species in the genus Chelonia.[1]

The appearance of the green sea turtle is that of a typical sea turtle. C. mydas has a dorso-ventrally flattened body, a beaked head at the end of a short neck, and paddle-like arms well-adapted for swimming.[2] Adult green turtles are known to grow up to one-and-a-half meters long. While individuals have been caught that reached weights of up to 315 kilograms, the average weight of mature individuals is around 200 kilograms. The largest Chelonia mydas ever recorded weighed 395 kilograms (871 pounds).[3]

Unlike the closely-related hawksbill turtle, the green sea turtle's snout is very short and its beak is unhooked. The horny sheath of the turtle's upper jaw possesses a slightly-denticulated edge while its lower jaw has stronger, more defined denticulation. The dorsal surface of the turtle's head has a single pair of prefrontal shields. Mature C. mydas front appendages have only a single claw (as opposed to the hawksbill's two), although a second claw is sometimes prominent in young specimens. The carapace of the turtle is known to have various color patterns that change over time. Hatchlings of C. mydas, like those of other marine turtles, have mostly black carapaces and light-colored plastrons. Carapaces of juveniles are dark brown to olive, while those of mature adults are either entirely brown, spotted or marbled with variegated rays. Underneath, the turtle's plastron is hued yellow. C. mydas limbs are dark-colored and lined with yellow, and are usually marked with a large dark brown spot in the center of each appendage.[4][5]

[edit] Habitat

Green turtles usually inhabit shallow waters associated with seagrass beds.[9] Seagrass meadows within inshore bays, lagoons and shoals are common locations where Chelonia mydas can often be found. This particular species is known to be very selective about their feeding and mating sites and entire generations will often alternately migrate between the same feeding and nesting areas.[2]

[edit] Feeding ecology

Adult Chelonia mydas is primarily herbivorous. It feeds almost-exclusively on various species of sea grasses and seaweed.[9] While mature green turtles are entirely herbivorous, juveniles are known to subsist on a plethora of marine invertebrates. Their digestive intake of plant matter grows larger as they age, until as mature adults they become obligate herbivores.[5]

[edit] Life history

Unlike most sea turtles, which spend most of their adult lives in the ocean, Pacific green turtles are known to willingly crawl onto secluded beaches during the day to bask in the sun.[5]

Green turtles are known to migrate long distances in-between their chosen feeding sites and the isolated islands and beaches from which they were hatched. Some C. mydas are known to swim distances of greater than 2,600 kilometers to reach their spawning grounds. Mature turtles will often return to the same exact beach from which they hatched from. Individual female green turtles usually mate every two to four years. Males on the other hand, are known to make the trip to their breeding areas every year.[10] As with many species that are found across a wide range of latitudes, mating seasons vary between populations. For Chelonia mydas in the Caribbean, mating season is from June to September.[2] Hawaiian green turtles nest from April to November.[citation needed] In the tropics, green turtles are known to nest throughout the year, with some subpopulations preferring particular times of the year. In Pakistan, Indian Ocean C. mydas nest all year-round but prefer to nest during the months of July and December.[8]

Green turtles reproduce in the typical way that marine turtles do so. After a lengthy mating ritual in the water, the females haul themselves onto the beach above the high tide line. Upon reaching a suitable nesting site, the gravid female then digs a hole with her hind flippers and deposits a number of eggs in the nest. The number of eggs laid per litter depends on the age of the female and differs from species to species, but C. mydas clutches range between 100 to 200 eggs. After laying eggs, the female then covers the nest with sand and returns to the sea.[5]

After around 45 to 75 days, the eggs hatch. As with other marine turtles, C. mydas eggs hatch during the night and the newly-emerged turtles instinctively head directly towards the water's edge. This undoubtedly is the most dangerous time in a turtle's life, as the hatchlings make their way to the water, various predators such as gulls and crabs pick off many turtles. A significant percentage of turtle hatchlings never make it to the ocean. Just like other sea turtles, little is known of the life history of juvenile green sea turtles. It is speculated that they take twenty to fifty years to reach mature size.[2] Individuals of the species are known to live up to eighty years in the wild.[5]

Green turtles are one of the turtle species known to undergo an arribada - an annual event describing the mass nesting of sea turtles. One of the most famous mass-nesting sites for this species is located on Ascension Island in the South Atlantic. Each year on the island, thousands of C. mydas create between 6,000 and 15,000 nests. These particular turtles are among the largest green turtles in the world, many more than a meter in length and weighing up to 300 kilograms.[citation needed]

Information from Wikepedia - http://en.wikipedia.org/wiki/Green_Sea_TurtleChelonia mydas, commonly known as the green sea turtle or green turtle, is a large sea turtle belonging to the family Cheloniidae. It is the only species in the genus Chelonia.^[1]

The appearance of the green sea turtle is that of a typical sea turtle. C. mydas has a dorso-ventrally flattened body, a beaked head at the end of a short neck, and paddle-like arms well-adapted for swimming.^[2] Adult green turtles are known to grow up to one-and-a-half meters long. While individuals have been caught that reached weights of up to 315 kilograms, the average weight of mature individuals is around 200 kilograms. The largest Chelonia mydas ever recorded weighed 395 kilograms (871 pounds).^[3]

Unlike the closely-related hawksbill turtle, the green sea turtle's snout is very short and its beak is unhooked. The horny sheath of the turtle's upper jaw possesses a slightly-denticulated edge while its lower jaw has stronger, more defined denticulation. The dorsal surface of the turtle's head has a single pair of prefrontal shields. Mature C. mydas front appendages have only a single claw (as opposed to the hawksbill's two), although a second claw is sometimes prominent in young specimens. The carapace of the turtle is known to have various color patterns that change over time. Hatchlings of C. mydas, like those of other marine turtles, have mostly black carapaces and light-colored plastrons. Carapaces of juveniles are dark brown to olive, while those of mature adults are either entirely brown, spotted or marbled with variegated rays. Underneath, the turtle's plastron is hued yellow. C. mydas limbs are dark-colored and lined with yellow, and are usually marked with a large dark brown spot in the center of each appendage.^[4][5]

[edit] Habitat

Green turtles usually inhabit shallow waters associated with seagrass beds.^[9] Seagrass meadows within inshore bays, lagoons and shoals are common locations where Chelonia mydas can often be found. This particular species is known to be very selective about their feeding and mating sites and entire generations will often alternately migrate between the same feeding and nesting areas.^[2]

[edit] Feeding ecology

Adult Chelonia mydas is primarily herbivorous. It feeds almost-exclusively on various species of sea grasses and seaweed.^[9] While mature green turtles are entirely herbivorous, juveniles are known to subsist on a plethora of marine invertebrates. Their digestive intake of plant matter grows larger as they age, until as mature adults they become obligate herbivores.^[5]

[edit] Life history

Unlike most sea turtles, which spend most of their adult lives in the ocean, Pacific green turtles are known to willingly crawl onto secluded beaches during the day to bask in the sun.^[5]

Green turtles are known to migrate long distances in-between their chosen feeding sites and the isolated islands and beaches from which they were hatched. Some C. mydas are known to swim distances of greater than 2,600 kilometers to reach their spawning grounds. Mature turtles will often return to the same exact beach from which they hatched from. Individual female green turtles usually mate every two to four years. Males on the other hand, are known to make the trip to their breeding areas every year.^[10] As with many species that are found across a wide range of latitudes, mating seasons vary between populations. For Chelonia mydas in the Caribbean, mating season is from June to September.^[2] Hawaiian green turtles nest from April to November.^{[citation needed]} In the tropics, green turtles are known to nest throughout the year, with some subpopulations preferring particular times of the year. In Pakistan, Indian Ocean C. mydas nest all year-round but prefer to nest during the months of July and December.^[8]

Green turtles reproduce in the typical way that marine turtles do so. After a lengthy mating ritual in the water, the females haul themselves onto the beach above the high tide line. Upon reaching a suitable nesting site, the gravid female then digs a hole with her hind flippers and deposits a number of eggs in the nest. The number of eggs laid per litter depends on the age of the female and differs from species to species, but C. mydas clutches range between 100 to 200 eggs. After laying eggs, the female then covers the nest with sand and returns to the sea.^[5]

After around 45 to 75 days, the eggs hatch. As with other marine turtles, C. mydas eggs hatch during the night and the newly-emerged turtles instinctively head directly towards the water's edge. This undoubtedly is the most dangerous time in a turtle's life, as the hatchlings make their way to the water, various predators such as gulls and crabs pick off many turtles. A significant percentage of turtle hatchlings never make it to the ocean. Just like other sea turtles, little is known of the life history of juvenile green sea turtles. It is speculated that they take twenty to fifty years to reach mature size.^[2] Individuals of the species are known to live up to eighty years in the wild.^[5]

Green turtles are one of the turtle species known to undergo an arribada - an annual event describing the mass nesting of sea turtles. One of the most famous mass-nesting sites for this species is located on Ascension Island in the South Atlantic. Each year on the island, thousands of C. mydas create between 6,000 and 15,000 nests. These particular turtles are among the largest green turtles in the world, many more than a meter in length and weighing up to 300 kilograms.^{[citation needed]}

Information from Wikepedia - http://en.wikipedia.org/wiki/Green_Sea_Turtle