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SHORT FEATURE BIKRAM KESHARI JENA Olive Ridley sea turtle HE Gahirmatha Marine Sanctuary Costa Rica, Chacocente and La Flor in conditions. It is found that the eggs Ton the coast of Odisha along the Nicaragua, Playa Escobilla of Mexico, hatched at temperature 31-32 degree Bay of Bengal has become an infamous are the major arribadas. Gahirmatha in centigrade produce only females, while a battleground between the fishing Odisha is the most important nesting site temperature 28 degree centigrade or less community and the Olive Ridley sea of the Indian Ocean ridleys. Apart from yields only males. turtles. Over-fishing has been causing Gahirmatha, there are two other places in The hatching takes place during large-scale death and destruction of Odisha, hosting the Olive Ridleys – river night in a bid to minimize the threat from the turtles. But if fishing is stopped, mouths of the Devi and the Rushikulya. predators like dogs, birds and jackals. thousands of people will suffer from Gahirmatha is supposed to be the This is an incredible survival strategy starvation. world’s largest breeding site of the Olive provided by nature. After hatching, Olive Ridley (named after H.N. Ridley turtles. The turtles start arriving the new born baby turtles immediately Ridley who first reported the sighting of in November every year on this sandy head for the open sea. These tiny turtles the turtle in Brazil in 1887) is one of the beach. The intensity of mating is high. are possibly guided by the reflection of seven species of sea turtles. The other six Adult females keep mating with more stars on the sea water or by the brighter are – Leatherback turtle, Green turtle, than one male throughout the season. horizon to find the exact direction to the Hawksbill turtle, Loggerhead turtle, Flat Once mating is over, the female turtles sea. They move in huge numbers towards Back turtle and Kemp’s Ridley turtle. embark on finding safer places on the the water. The Leatherback turtle is the largest and beach to dig pits for laying eggs. The period between hatching and the only one not to have a hard shell. Sea It is observed that nesting on the reaching the sea is crucial for the babies. turtles are found in all the waters except Gahirmatha beach gets under way with During the stampede to reach the sea the Arctic. The Olive Ridley also known the blowing of the southerly wind. Nesting water, the death toll is very high. They as Pacific Ridley sea turtle is a medium of the ridleys is usually a nocturnal event. also become frequent prey for the seagulls, sized species of sea turtle found in warm The pits are flask-shaped holes dug by the bigger fish and ghost crabs. During this and tropical waters, primarily in the turtles by scooping soft sand with their transition period, the mortality rate is so Pacific and Indian Oceans. flippers. A female produces eggs ranging high that one in every 1000 baby turtles is Olive Ridley turtles are best known from 100 to 180. After releasing eggs, the able to survive. for their synchronized mass nesting, turtle covers the pit with sand and returns It is a wonder of nature that the called Arribadas. There are several to the sea. The eggs inside the pit are babies of the olive ridley turtles live their breeding grounds (Arribadas) around incubated by the sun and metabolic heat. entire life without their mothers. Once the world. Arribada is derived from a The incubation period is between 45 safely into the high seas, their chances Spanish word meaning ‘Arrival’. In the and 51 days under normal conditions, but to reach adulthood increase manifold. It Pacific region, Nancite and Ostional of may extend to 70 days in poor weather takes about 15–30 years for a baby turtle SCIENCE REPORTER, NOVEMBER 2014 54 SHORT FEATURE “Biological and Behavioral Aspects of Olive Ridley Turtles along the Orissa coast of India” said that the yearly turtle peaceful nesting sites, unwanted noise mortality is related to developmental activities is well over most likely to compel the marine guests 10,000 to abandon Gahirmatha. Yet another threat is artificial light since the eemployed by the ports and refineries. mid-nineties. TThe artificial light adversely affects the nnew born babies on the beach. There is Olive Ridley turtle eggs aan interference of natural and artificial (Courtesy: Odisha Forest Department) llilights which would drive the babies in the wwrong direction leading to early death. Keeping this in view, the government ddeclared Gahirmatha a marine sanctuary iin 1997. Now, fishing is banned for a pperiod of seven months (November-May). TThe total prohibited area is 20 kilometers iininto the sea along the coast ranging Mass nesting at Gahirmatha ffrfrom Dhamra in north to the mouth of tththe Rushikulya River in the south. This mmarine turtle has now been classified as vvulnerable by the International Union ffor Conservation of Nature and Natural to become mature. After spending a long revoked the egg collection license in 1975. Resources (IUCN). It is also listed in the time in the sea waters, they have to return Two years later the railway authorities Section 13 of Part 2 of Schedule 1 of the to the same beach (where they were born stopped booking turtles for the Calcutta Wildlife Protection Act (1972) of India as years back) as adult turtles for breeding. market. Anti-turtle activities on land have a protected species. This lifestyle of birth on land and been brought under stringent regulation In 1998, the Wildlife Protection growth in sea water is unique to the olive in order to protect the endangered marine Society of India (WPSI) launched ridley turtles. This age-old natural cycle species. “Operation Kachhapa” to safeguard the at Gahirmatha was first mentioned by However the off-shore problem, turtles on the coast of Odisha. One of Captain Alexander Hamilton in his travel commercial fishing in particular, remains the main aims of the operation was to account during his visit to Odisha in 1708. a matter of grave concern. Owing to encourage trawlers to use “turtle excluder This is also believed to be the earliest indiscriminate fishing, thousands of device (TED)”. written record of any turtle rookery in the olive ridley turtles are inflicted with fatal Under another programme at world. injuries. As a bitter consequence, a massive Gahirmatha, the eggs that are more However, Gahirmatha gained scale of carcasses is found scattered along vulnerable to destruction are relocated prominence when H.R. Bustard, the the beach every year. In 2009, the Wildlife to safer hatcheries. At the same time, if then United Nations (UN) representative Institute of India in its report “Biological the fishermen could also be relocated for conservation of crocodiles in India, and Behavioral Aspects of Olive Ridley elsewhere, it would provide further spotted the site in 1974. Before Bustard’s Turtles along the Orissa coast of India” impetus to the conservation of the turtle. said that the yearly turtle mortality is well discovery, there was a relentless Despite such effective measures, over 10,000 since the mid-nineties. There harvesting of turtles and related products. the threat on the Gahirmatha marine are also some conflicting reports on the According to some historical records, the sanctuary is on the rise. According to issue. Some non-governmental sources local people used to collect the turtle eggs Captain Hamilton, the total nesting claimed the death figure to be very close from the Gahirmatha beach. In return, area once extended to a length of 100 to 100,000. Modern fishing methods such they had to pay the so called “egg tax” to kilometers. By the 1970s, this length was as shrimp trawling, gill nets, ghost nets, the king of the erstwhile princely state of down to 25 kilometers. By the year 1989, long-line fishing and pot fishing are Kanika. Huge loads of marine turtles are the total breeding ground had contracted blamed for this ever rising death toll. said to have been transported by train to an island of length of mere 4 kilometers. to Kolkata. This brutal trade went on till With the construction of modern For the conservationist, it is now an 1974. infrastructure like ports and oil refineries, uphill task to save the olive ridley turtles In the aftermath of Bustard’s visit, a new set of problems has taken shape. as they face stiff competition to find space this environmentally sensitive site came According to environment experts, once for breeding. into limelight. The government brought the ports become operational, there Gahirmatha into the ambit of conservation would be a kind of underwater vibration Mr Bikram Keshari Jena is a Welfare Extension in 1975, by declaring it a part of the newly during the ship movement which may Offi cer under the Government of Odisha. created Bhitarkanika Wildlife Sanctuary. disturb the turtles. As the sea turtles are Address: Khalipatana, Panchirida, Nayagarh, Subsequently, the state forest department widely known for choosing secluded and Odisha-752080; Email: [email protected] 55 SCIENCE REPORTER, NOVEMBER 2014.