Olive ridley turtle
Olive Ridley, Pacific Ridley; Ridley du Pacifique, tortue bâtarde, tortue de ridley, tortue olivâtre (Fr); Tortuga golfina, tortuga olivacea (Sp)
Approx. 800,000 nesting females
IUCN: Vulnerable A2bd CITES: Appendix I CMS: Appendix I and II
Illegal harvest of eggs continues
The olive ridley looks very similar to the Kemp's ridley, but has a deeper body and slightly up-turned edges to its carapace (shell).
The average length is 70cm, and adults weigh approximately 45kg.
Rusty coloured carapace.
After reaching sexual maturity when they are about 12 years old, many thousands of females emerge from the sea and nest simultaneously over a period of 2 to 3 days. These arribadas (a Spanish word meaning 'mass arrivals') may be an adaptation against predation, and one reason for the success of this species.
However, the olive ridley often chooses small, narrow beaches and their nests may be so closely packed that subsequent waves of females often dig up other nests in efforts to lay their own eggs. Arribadas may be repeated 2 to 7 times a season.
This species feeds essentially on crabs and shrimps, but also jellyfish, small invertebrates, tunicates, small invertebrates and fish eggs. Individuals have been captured in prawn trawls at depths of 80 to 110m, and are therefore considered capable of foraging at these depths.
Current Population and Distribution
Olive ridleys occur through the Antilles, around the north coast of South America, in West Africa, the Indian Ocean, Australia and southeast Asia. There are also many important nesting and feeding grounds on the east Pacific coast from as far north as Canada to as far south as southern Peru.
Nesting occurs at low frequency throughout much of its range, with the highest concentrations of the olive ridley found on the coast of Orissa state, India. The principal beaches are Garhimatha, Ruchikulya and Devi River mouths. On the Pacific coast of Costa Rica, the main nesting beaches are Nancite and Ostional, and La Escobilla on the coast of Oaxaca, Mexico. Populations in northern Australia and south-east Asia are known to be different genetic stock to the Orissa turtles. Populations of olive ridleys are reported to have declined in Pakistan, Myanmar, Malaysia and Thailand, and possibly on the east coast of India, south of Orissa and in the Andaman and Nicobar islands.
A recent estimate of 800,000+ female olive ridleys has been made.
Angola, Australia, Bangladesh, Brazil, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Honduras, India, Indonesia, Kenya, Madagascar, Malaysia, Mexico, Mozambique, Myanmar, Nicaragua, Oman, Pakistan, Panama, Papua New Guinea, Peru, Senegal, South Africa, Sri Lanka, Suriname, Tanzania, Thailand, Trinidad and Tobago, Venezuela.
Southern Australian Marine, Benguela Current, Humboldt Current, Agulhas Current, Western Australia Marine, Gulf of California, Canary Current, Sulu-Sulawesi Seas, Bismarck-Solomon Seas, Banda-Flores Sea, Great Barrier Reef, Palau Marine, Andaman Sea, East African Marine, West Madagascar Marine, Mesoamerican Caribbean Reef, Greater Antillean Marine, Southern Caribbean Sea, Northeast Brazil Shelf Marine
What are the main threats?
- Habitat loss and degradation
- Wildlife trade
- Collection of eggs and meat for consumption
- Incidental capture (bycatch)
- Climate change
Olive ridleys were once killed in large numbers for meat and leather. There were many economically important slaughterhouses on Mexico's Pacific coast, where officially over 1 million turtles were killed each year during the 1960s. This slaughter was reduced when legal quotas were introduced, although a smaller illegal industry persists.
Why is this species important?
Olive ridley turtles feed on invertebrates and may play important roles in both open ocean and coastal ecosystems.
What is WWF doing?
- Action to address the impacts of climate change.
- Monitoring the migration patterns of marine turtles.
- Improving and supporting trade controls.
- Protecting nesting sites.
- Reducing bycatch and promoting smart fishing.
How you can help
- Send a turtle to rehab! Help the recuperation process for thousands of sick and injured turtles.