SEA TURTLE

SEA TURLES (Superfamily Chelonioidae) are turles found in all the world's oceans except the Arctic Ocean. There are seven living species of sea turtles: flatblack, green, hawksbil, kemp's ridley, leatherback, loggerhead and olive ridley. The East Pacific subpopulation of green turle was previously classified as a separate species, the black turle, but DNA evidence indicatesthat it is not evolutionarily distinct from the green turtle. all species except the leatherbackare in the family Cheloniidae; the leatherback belongs to the family Dermochelyidae and is its only member.

Anatomy
Although they have been around for tens of milions of year since the mesozoic, the body plan of sea turtles has remained relatively constant. Sea turtles possess dorsoventrally-flattened bodies with two hind legs and highly-evolved pddle-like front arms. Sea turles are one of the oly reptiles witha hard shell. Their shells are made of solid bone covered by large, thin scales, and they protect the whole of animal's body with the exception of the head, legs and tail. However, to make up for that vulnerability, they have the ability to pull their heads inside their shells when threatened. Many can also pull their legs and tail into their shell. Sea turtle flippers are highly evolved; some species of sea turtles can even climb rocky shores with their adapted flippers for their advantage to elude predators. Different species are distinguished varying anatomical aspects: forintance, the prefrontal scales on the head, the number of and shape of scutes on the carapace, and the type of inframarginal scutes on the plastron. The leatherback is the only sea turtle that does not have a hard shell, instead carrying a mosaic of bony plates beneath its leathery skin. It is the largest of the sea turles, measuring six or seven feet (2 m) in length at maturity, and three to five feet (1 to 1.5 m) in width, weighing up to 1300 pounds (650 Kg). Other Species are smaller, being mostly two to four feet in length (0.5 to 1 m) and proportionally narrower.

Distribution
The superfamily cheloinoidea has a world wide distribution, sea turtles can be faund in all oceans except for in the polar regions. Some species travel between oceans. The flatback turtle is faund solely on the northern coast of Australia.

Conservation

All species of sea turtle are endangered.The leatherback, kemp's ridley, and hawksbill turtles are listed as critically endangered. The olive ridley and green turtles are considered endangered, and the longgerhead is a threatened species. The flatback's conservation status is unclear due to a lack of research data.
Sea turtles usesd to be hunted on a large scale in whaling days their meat, fat and shells. Coastal peoples have also been known to gather turtle eggs for consumption. One of their most significant threats now comes from bycatch due various fishing methods, long-line fishing has been blamed as one of causes of accidental sea turtle deaths, and the black market demand for tortoiseshell for both decoration and supposed health benefits.
Nets used in shrimp trawling nad fishing have been known to cause the accidental deaths of sea turtles. The turtles, as air-breathing reptiles, must surface to breathe. Cought in fisherman's net, they are unable to go to the surface to breathe and suffocate to death in the net. early 2007, almost a thousand sea turtles were killed inadvertently in Bay of Bengal over the course of a few months as result of becoming trapped in fishing nets.

However some relatively inexpensive changes to fishing techniques, such as shlightly larged hooks and traps from which sea turtles can escape, can dramatically cut the mortality rate. Turtle Excluder Devices (TEDS) have reduced sea turtle bycatch in shrimp net by 97 percent. Another danger comes from marine debris, especially from abandoned fishing nets in which they can become entangled.
Beach development is another area which poses threats to sesa turtles. SInce sea turtles return to the same beach locations to nest, if these areas are developed they may be left with nowhere to nest, or their nesting locations may be threatened by human activity. Therefore, there has been a movement to protect these areas, in some cases by special police. In some areas, such as the east coast of Florida, after the adult turtles lay their eggs, they are dug up and relocated to special fenced nurseries where they can be protected from beach traffic. this is not the best thing to do, as many turtle species return to the beach on which they were born. Hatchlings find their way to the ocean by crawling towards the brightest horizon, but often become disoriented on developed stretches of coastline. special lighting ordinances may also be enforced to prevent light sining on the beach and confusing young hatchling, causing them to the crawl towards the light and a away from water, usually crossing a road. A turtle-safe lighting system uses red light in place of white light as sea turtles can't see red light.

Another major threat to sea turtles is the black market trade in aggs and meat. this is a pervasive problem throughout the world, but especially a concern in the, Philippines, Indonesia, India and throughout the costal nations of latin America. Estimates are high as 35,000 turtles killed a year in Mexico and the same nurber in Nicaragua. Conservationists In Mexico and a United States have launched "Don't Eat Sea Turtle" campaigns in order to reduce the urban black market trade in sea turtle products. these campigns have involved figures such as Pope John Paul II, Dorismar, Los Tigres Del Norte and Mana. Sea are reptiles, not fish. Conservation organizations have written letters to the Pope asking that he declare turtle meat.
Moreover, global warning can also cause a threat to sea turtles. Since temperatures in the sands define the sex of the turle while developing in the egg, many feared rising temperatures worls only produce one sex, but more research remaind to be done in order to understand how climate change might affect sea turtle gender distribution.
Sea turtle can also be effected by Fibropapillomatosis, a disease that has been found amongst sea turtle populations and causes tumors.
Injured sea turtles are sometimes able to be rescued and rehabilitated by professional organizations such as the Mote Marine Laboratory in sarasota, Florida, the Marine Mammal Center in Northen California, and the ClearWater in South Padre Island, TX. one such turtle, named Nickel for coin that was found lodged in her throat, lives at the Shedd Aquarium in Chicago.
On September,2007 Corpus Christi, Texas wildlife officials found a record of 128 Kemp's ridley sea turtle nests on Texas beaches, including 81 on North Padre Island (Padre Island National Seashore) and 4 on Mustang Island. Wildlife offcials released 10,594 Kemp's ridley hatchling along the texas coast this year. The turtles are endangered due to shrimpers' nets and they are popular in Mexico as boot material and food.
In 2007, the U.S. Fish and Wildlife Service and National Marine fisheries service finished a joint study assessing the worldwide populations of all sea turtle species. It was determined that leatherback, the hawksbill and the Kemp's Ridley populations were endangered while that of green turtles and olive ridleys were threatened.
In Southeast Asia, the Philippines has had several initiatives dealing with the issue of turle conservation. in 2007, the province of Batangas in the Philippines declared the catching and eating of Pawikans illegal. However, the law seems to have little effect as pawikan eggs are still in demand in batangan markets.

Today, one can easily purchase three Pawikan eggs for a more PhP20. on january 23, 2008 the Coastal Resource Management Coordinator arrested and detained fisherman Israel Jimenez,40 from Poblacion, Bacuag, Surigao del Norte who slaughtered and endangered sea turtle, pending the filling of case by The Bereau of Fisheries and Aquatic Resaurces.
In September of 2007, several chinese poachers were apprehended off the Turtle Island in the country's southernmost province of Tawi-Tawi. The poachers were discovered to have collected more than a hundred sea turtles, along with 10,000 turtle eggs.