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The female crawls up the beach to a point above high tide, using all four flippers begins to settle her self comfortably into the sand. She will then dig an egg pit removing the sand using her hind flippers alternatively to create a depression. The flipper is used as a scoop, it is curled and lowered carefully retrieve a “handful” of sand. The scoop of sand is sent directly backward to clear the hole. The whole that is dug is about 70-90 centimeters for the green turtle. (2) She then deposits the eggs, usually two at a time that are about 5 centimeters in diameter. The groups of eggs laid are referred to as a clutch. (7) Several clutches could be laid in one season. A clutch may have more than 200 eggs or as few as one. (3) The female will then carefully cover the eggs using her front flippers. This whole process can take a few hours. The mother will leave her young behind; her part is done.

Offspring

The incubation period for the green turtle is between 54-63 days. (2) Many experiments have shown that the temperature at which the nest is incubated at determines the sex of the turtle. Temperatures minutely above the constant temperature for any given moment of time will produce female and then the temperature below the constant temperature threshold will produce males. (2) When the turtle hatches, because it is so high on the beach, and the hatchling is so small it is unable to see the ocean. Yet the turtle is able to detect the direction of the beach and moves toward the ocean in either day or night.

Senses

Turtles appear to depend on their sense of smell the most. They have good sight and can distinguish differences in the intensity of light and can recognize up to four colors- blue, green, yellow and red. (3) Only the eyes of the sea turtles are fully adapted for vision under water they are able to make alterations in the curvature of their lens.

Turtles respond readily to vibrations in the water and in the air. Turtles seem to have a sensitivity and response to aerial sounds. In American in the year1915 experiments reported that turtles do hear but the Japanese contradicted this statement ten years later. Three years later a Soviet investigator concluded that turtles do hear, but his paper was published only in the U.S.S.R. and largely ignored elsewhere. In 1966 two Americans demonstrated that at least some turtles hear low-frequency airborne waves, ranging from about 20 to about 1,000 cycles per second. Whereas the corresponding figures for humans is 20 to 20,000 cycles per second. The fact that the number of cycles heard by turtles is much lower than that of man may explain the difficulty in arriving at a conclusion for the turtle. (3)

With the exception of courting or mating, turtles seldom emit sounds. Unless provoked, the sound is usually minute grunt or roar. When provoked, a loud cry can be heard.

Experiments have shown that turtles are intelligent animals. Then learn quickly; some say they are comparable to a laboratory rat.

Economic value

The tortoise as well as the green turtle have been victims of man?s appetite. The green turtle, with its distribution extending around the world, has supplemented the diet of peoples of more different cultures than has any other wild vertebrate. (3) Tortoise populations of many oceanic islands has dwindled; it has been estimated that 10,000,000 land giants were taken from the Galapagos Islands as food supply for the early whaling ships. Turtle eggs are also prized as food. These are deposited in such abundance on certain beaches that harvesting them has become a national industry in Malaysia.

Unfortunately not just the meat has been sought after by man but the beauty of the shell as an ornament has been coveted as well. Fortunately plastic replications can be made and sold to those that just can?t live without them.

Conclusion

The green sea turtle is a large, remarkable creature of the sea. They are found all over the world. Their diet is varied, enabling them to travel anywhere in the sea. The egg laying process of the female is meticulous and time consuming; the hatchlings are born on land and run to the crest of the sea to begin their lives. The turtle has many predators from the bird that will attack the eggs to the larger squid that will eat the small turtle in the sea. And then there is the man, the green turtles largest preditor, which will hunt the turtle, eat the turtle and kill it with the pollution thrown into the sea.

Bibliography

(6) Blakeslee, April. (1999).?Sea Turtle.? http://www.cyhaus.com/marine/turtles.htm (November 5, 2000)

(3) Encyclopedia Britannica. (2000). ?Green Turtle?. http://www.britannica.com/bcom/eb/article/1/0,5716,68181+1+66460,00.html?query=green%20turtle October 10, 2000

(4) Gould, James L. and Keeton, William T. (1996) Biological Science 6th edition New York W.W. Norton & Company p A1-A5

(5) Hawaii Preparatory Academy (2000). “Green Sea Turtle” http:www.hpa.edu/TurtleTagging/GreenTurtle.html (November 5, 2000)

(2) Kaska, Y. (1998). Natural Temperature regimes for loggerhead and green turtle nests in the eastern Mediterranean. Canadian Journal of Zoology, 76, 723-729

(1) Reisz, R, and

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