By Annemarie Kramer
Latin name:
Chelonia mydas
Geographic Area:
Atlantic, Indopacific, Mediterranean Sea, Mexican Gulf Coast, South American Coasts
Weight:
Up to 200 kg (440 lbs)
Size:
Up to 120 cm (4 ft)
Distribution:
This species is found circumglobally on tropical and subtropical parts of the Atlantic, the Pacific and the Indian Ocean. They normally stay close to shore, but when migrating from feeding to nesting grounds, they often swim far offshore. Important nesting beaches are found on many tropical continental coasts such as Costa Rica and Surinam, but as well on small islands off the coasts e.g. offshore the Great Barrier Reef in Australia. Some of those nesting beaches are found on small islands in the middle of the ocean e.g. Ascension or the Atol de las Rocas, which are islands in the central Atlantic Ocean. This species of sea turtle prefers to stay close to shallow, coastal areas and reefs where seagrass and algae grow.
Nesting behaviour:
Females always come back to the same beach to lay their eggs, very probably to the same beach where they have hatched themselves. An average of 112 eggs is laid, always at night, into an egg chamber which she digs in the sand and then covers. Female green turtles nest every 2 to 4 years, laying up to 5 batches of eggs in a single nesting season, with an interval of two weeks between each nest.
After approximately 8 weeks the young turtles hatch, this usually happens at night and they start moving towards the sea. Scientists think that during their journey towards the sea the turtles get imprinted on the characteristics of their natal beach and thus can find their way back as adults. It is known that the hatchlings start swimming towards the open ocean and come back only years later. Where they go and what they do during their juvenile years is very poorly known. Green turtles take 25 years or more to reach sexual maturity, and only then they come back to the mating grounds near the shores. |
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©Turtle Foundation
©Turtle Foundation
©Michael Carey
©Turtle Foundation
©Turtle Foundation |
Food sources:
Young green turtles feed on everything they find, later their diet is more restricted: seagrass, algae but as well animals like salps, jellyfish and sponges. In some areas they have been found to feed also on snails, crabs and fish.
Special remarks:
The green turtle has been used to make turtle soup and has its name from the green layer of fat below the carapace. In many countries people still eat turtle meat and eggs.
Literatur:
Lutz, P. L. & J. A. Musick (Hrsg.), 1997. The Biology of Sea Turtles. 432 Seiten. CRC Press. Boca raton, London, New York, Washington, D.C.
Lutz, P. L., J. A. Musick & J. Wyneken (Hrsg.), 2003. The Biology of Sea Turtles. Volume II. 455 Seiten. CRC Press. Boca raton, London, New York, Washington, D.C.