The Olive Ridley Sea Turtle

The Olive Ridley Sea turtle is one of the smallest turtle species like its sister species Kemp's Ridley Sea turtle. They were named after Mr. H.N. Ridley who discovered this species on Fernando de Noronha Island in Brazil in the year 1887. It is called olive Ridley because of the greenish color of its skin and carapace. Its binomial name is Lepidochelys olivacea and it is also known as the Pacific Sea turtle.

Olive Ridley Sea turtles can weigh up to 100 pounds (45Kilograms) and are about 2 feet (65 centimeters) long. Their head and shell is a bit smaller than Kemp's Ridley Sea turtle. Size of these turtles differs from region to region. Their carapace is usually of greenish color but sometimes it looks reddish because of red algae growing on the carapace. Olive Ridley turtles have unique lateral scute. Male turtles have bigger tail than female turtles which is used males during copulation. Enlarged claw enables male turtles to have a good grasp of the females. Their expected lifespan is 50 years.

They are found mainly in tropical and subtropical areas. They prefer warm waters of the Pacific, Atlantic and Indian Ocean. They range from Australia, southern Africa and New Zealand to Arabia, Japan and Micronesia in the Indian and Pacific Ocean and in the Atlantic they are found in the western coast of Africa, northern Brazil, Venezuela, Suriname, Guyana and French Guyana. Olive Ridley turtles have been considered as the most abundant turtles in the world. But a case study from 1982 to 2008 shows that the number of turtles has been decreased about 28 to 32%.

They are carnivorous in nature. They feed on especially invertebrates and protochordates which are easily available in marine waters and estuarine. Sea urchins, bivalves, crabs, shrimp, tunicates, bryozoans, jelly fish, snails, sipunculid worms, rock lobsters etc. are their main food. They have been found to eat filamentous algae where there is deficit of other preys. Scientists have found cannibalistic behavior too in olive Ridley sea turtles.

The female members of this small and beautiful creature arrive at their nesting sites in large groups which are called arribadas in Spanish. They take the help of the tide and the wind to reach their destination. Females can lay up to hundred eggs while nesting and they can nest three times per year. They usually nest from June to December.

These turtles have been declared as 'Vulnerable' in the conservation status by IUCN and enlisted as an endangered species. The reason behind the dramatic decline in the number of olive ridley in the last few years is the massive collection of turtle eggs and hunting of adult female turtles during nesting period. They are hunted for fertilizer, food, bait, leather etc. Extensive harvesting of this species is another reason for this decline. Some are eaten up by predators. Especially juveniles are killed by raccoons, crabs, fishes, Iguanas, birds, coyotes and snakes and adults are usually eaten up by sharks. Besides, gill nets, trawling, ghost nests, pot fishing and long line have also affected the number of olive green sea turtles significantly.