The Olive Ridley sea turtle has been spotted in the tropical regions of the Pacific, Atlantic, and Indian Oceans. They are still considered to be widespread although the nesting sites are being depleted by the rise of human development on coastal properties.
The main threats are of the commercial harvest of adults, incidental catch in shrimp trawls, and the harvesting of their eggs. Females can lay between 105 and 115 eggs in each clutch.
Read on to learn lots more about them!
Olive Ridley Sea Turtle Facts
- Scientific Name: Lepidochelys Olivacea.
- Size: The average adult size can range between 22 to 30 inches (55 to 75 cm)
- Weight: Average nesting females can weigh around 77 pounds (35kg) and up to 100lbs (45kg)
- Habitat: These turtles are distinct from Kemp’s Ridley sea turtles in that they favour warm waters and frequent South Atlantic, Indian Oceans, and Pacific Oceans.
- Food: This turtle is primarily an omnivore, one that can survive on both plant and meat for food. The diet consists of jellyfish, snails, and crabs as well as algae and seaweed.
- It has an IUCN Red List Status of “Vulnerable”. The US officially listed it as “Threatened” since 1978. The population has declined by 50% since the 1960s and is on a downward trend to this day. On average, they nest thrice yearly and hatch 100 eggs per female. The population estimate for nesting females is 800,000.
What is the Olive Ridley sea turtle?
Olive Ridley sea turtles, just like the Kemp’s Ridleys, are both the smallest among sea turtles. It is named so basically due to its greenish shade on both its skin and its carapace or shell.
Some interesting Olive Ridley sea turtle facts
- Male Olive Ridleys have longer tails than females.
- The chief arribada nesting beach is located in La Escobilla, Mexico. 450, 000 females nest on its shore.
- These can dive 500 feet deep just to feed on bottom-dwelling crustaceans.
- The average life span in the wild is 50 years.
- This small sea turtle weighs 17 grams at birth.
- Females have more rounded shells compared with the males.
- A 1996 research reveals that about 60,000 sea turtles in Central America (most of which are Olive Ridleys) get caught and drowned in shrimp trawl nets every year.
Where do Olive Ridley sea turtles live?
Olive Ridleys are observed living in areas around New England or Mid-Atlantic, the Pacific Islands, the Southeast, and the West Coast. Trans-Pacific ships report sightings of these turtles 2,400 miles offshore. In the Atlantic Ocean, they choose the West African and South American coasts. In the Eastern Pacific, they stay along the coasts of Southern California to Northern Chile.
The head of Olive Ridley sea turtles is quite small. In fact, Olive Ridleys feature slightly smaller heads and shells compared with Kemp’s Ridley sea turtles.
The shell is bony. It doesn’t have ridges. You can see six smooth, circular, and large scales along the carapace. Although quite similar, the body is deeper compared with Kemp’s Ridley sea turtles.
Olive Ridleys have one to two claws on the front and back flippers. At times, an extra claw may present on the front flippers. Hatchlings are black with a greenish tinge when they come out. Juvelines turn a charcoal grey shading. Adults feature dark grey and green colours.
The species is mostly solitary. Olive Ridley sea turtles prefer the open ocean. You can spot them in estuaries and coastal bays. They tend to stay offshore wading along surface waters.
Though solitary in nature, they will migrate from long distances; from hundreds to thousands of miles each year to gather in groups for a mass nesting called arribada. They travel a long way with the help of the tides and the winds that carry them back to the shores of their nesting sites.
Olive Ridleys hear differently. Their ears pick up vibrations and perceive sounds, objects, and distances accordingly. The sense of smell is acute and helps them dive under turbid waters to catch their prey. The sight responds to light and gets direction from it.
What do Olive Ridley sea turtles eat?
Olive Ridleys have very powerful jaws. Their primary foods include shrimps and crabs, tunicates, fish, molluscs, and other small sea creatures. They also graze the bottoms for seaweed and algae.
These smaller sea turtles are equally agile and expert in the waters. Their flippers and shells are shaped perfectly for smooth navigation underwater. They love being in the ocean but females will leave the waters during nesting time. The swim back to nesting shores requires them to come up to the surface for air every few minutes. But when they are at rest, they can stay underwater for long periods of time.
Olive Ridley sea turtles lay eggs as a large group. This synchronized mass nesting is called an arribada. Once each year, female Olive Ridleys gather back to their home nesting beach in thousands. They lay eggs together. Incubation takes about 50 to 58 days after which you can see hatchlings making their way for the shores.
Each female lays 100 eggs on average and nests up to 3 times per year. Nesting sites are scattered all over the world on both tropical and subtropical beaches. Nesting season falls from June to December.
What are the predators they face?
Hatchlings can fall prey to many types of predators, some of which are raccoons, snakes, pigs, birds, and even crabs. A lot of Olive Ridley hatchlings never reach the ocean. Sharks prey upon the adult ones.
Why are Olive Ridley sea turtles endangered?
Olive Ridleys used to thrive in large numbers, possibly the most abundant of all marine turtles in the past. However, the species suffered a rapid decline. The population remains vulnerable to extinction.
Efforts to protect them are in place but there are still people out there who hunt these sea turtles for their eggs, skin, or meat. Bycatching is a constant problem in some areas where fishing nets capture and drown these turtles.
With commercial developments around beaches, nesting habitats are also in danger of destruction. This poses a great threat since Olive Ridley sea turtles tend to nest in a few places only.
The loss of one nesting beach can have a huge impact on the population. Chemical pollution and marine debris are also major concerns. Olive Ridleys and other sea turtles can die from chemical waste and rubbish that they either consume or get trapped in. Clean-up drives are currently being promoted in order to raise worldwide awareness.
Olive Ridley Sea Turtle Mini Documentary
|References: Groombridge, B. 1982. The IUCN Amphibia Reptilia Red Data Book:Testudines, Crocodylia, Rhynchocephalia. IUCN, SwitzerlandPhoto courtesy of NOAA|