Olive ridley sea turtle

Olive Ridley
Conservation status
Vulnerable  (IUCN 2.3)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Testudines
Family:	Cheloniidae
Genus:	Lepidochelys
Species:	L. olivacea
Binomial name
Lepidochelys olivacea (Eschscholtz, 1829)

Also see: Kemp's Ridley turtle.

The Olive Ridley (Lepidochelys olivacea), also known as the Pacific Ridley, is one of the smallest species of sea turtle. It is named for the olive-green color of its heart-shaped shell.

Anatomy and morphology

These lightly-built turtles have an average weight just over 100 lb (up to 50 kg.). They have a high-domed shell, with a carapace length of only 30 inches (70 cm). The carapace is made up of five pairs of coastal scutes, with occurrences of up to 6 to 9 divisions per side. The margins are smooth. The carapace is a dark olive green in color with a yellowish underside. The head is large.

Distribution

It is usually found in the Indo-Pacific and Atlantic oceans. The common name in Spanish is tortuga golfina, del golfo o lora.

The beaches of Orissa, India provide one of the last nesting grounds of the Olive Ridley turtles in the world. In addition, trawling and offshore drilling for oil and gas has been blamed for the death of more than 20 Olive Ridley turtles, which have washed ashore in the last ten years.

Though listed by the US Endangered Species Act, populations in the Atlantic Ocean continue to dwindle, while the populations found in areas around the Pacific Ocean seem to be on the rise. Furthermore, their ability to reproduce in the Red Sea was thought impossible, however, recent evidence suggests that they do indeed hatch in Eritrea amongst other places in the Red Sea.

In Costa Rica is the one of the most ìmportant nesting of this turtle. Ositonal Beach in Guanacaste Province has the mayor concentration of this turtles monthly, where the "arribadas" occur every month. In october and november is when Olive Ridley turtle nest in mayor quantity in this place (aproximately 200 turtles per hour). Nancite Beach and Camaronal Beach in the same province of this Central American country receive a lot of Olive Ridley Turtle, but less than Ostional.

In the Indian Ocean, a major nesting ground for the species can be found in the Indian state of Orissa. Beaches in Devi, Gahirmatha and Rushikulya are known nesting sites for the L. olivacea Indian Ocean population. In 2007, around 130,000 turtles nested on the beaches of Gahirmatha.

Lepidochelys olivacea distribution map. Red circles are major nesting grounds. But the construction of Dhamra Port by TATA Group is supposed to be a major threat to these turtles.Yellow circles are minor nesting beaches.

They are common in the Bay of Bengal, seen especially along parts of the Tamil Nadu coastline, including within the main city, Chennai. Olive Ridleys are seen frequently in laying eggs in the shore of Saint Martin's Island in Bangladesh. . Apart from anything else, this initiative proves that the species breeds in some numbers in Bali which is not shown as a breeding locality on the map accompanying this article.

It is believed that Olive Ridley turtles return to nest on the same beach they are hatched. If this is the case, then on these beaches where efforts are made to protect the eggs and hatchlings there should be rises in the numbers returning to nest in future.

Ecology and life history

Olive Ridleys are omnivorous, feeding on crabs, shrimp, rock lobsters, sea grasses, algae, snails, fish, sessile, pelagic tunocates and small invertebrates. They are sometimes seen feeding on jellyfish in shallow waters. These turtles forage offshore in surface waters and can dive to depths of at least 150 meters (500 feet).

Conservation

An Olive ridley sea turtle laying eggs.

Two Olive Ridley hatchlings moving toward the water after their release from a conservation facility in Mexico.