Sea Turtle Species Profiles
Olive Ridley Sea Turtle
Scientific Name: Lepidochelys olivacea
IUCN/Conservation Status: Vulnerable - According to the International Union of the Conservation of Nature, (IUCN) the olive ridley is considered Vulnerable (Abreu-Grobois & Plotkin, 2008). This indicates that the species is not endangered but populations are still at high risk of extinction in the wild. Olive ridleys are considered Threatened by the U.S. Endangered Species Act and therefore protected in the U.S. While the population of olive ridleys has decreased due to human causes, they are considered the most abundant sea turtles in the world (NOAA, Olive Ridley Turtle, n.d.).
Habitat/Distribution: The olive ridley can be found in tropical and temperate areas of the Pacific, Atlantic, and Indian oceans. Unlike the Kemp’s ridley, which prefers coastal waters, the olive ridley is found in open ocean habitats. This species cannot be found nesting in the U.S. but can be found passing through the Pacific waters of the West Coast, as far north as Oregon.
Diet: Olive ridleys are omnivores that eat shrimp lobsters, jellies, mollusks, tunicates, and algae.
Size: By the time they reach adulthood, olive ridley sea turtles measure 61 to 76 centimeters (2 to 2 and ½ feet) in length and weigh between 80 and 110 pounds.
Distinguishing Characteristics: The olive ridley is distinguishable by its varying number of lateral scutes. While other species have consistent numbers of lateral scutes, some olive ridley’s will only have 5, and others have as many as 9. They are named for their olive-colored carapace, which is heart-shaped and they look similar to Kemp’s ridleys.
Maturity and Reproduction: Olive ridley sea turtles mature between 10 and 18 years of age.
Nesting: Similar to the Kemp’s ridley, olive ridleys are known for nesting in arribadas. Females lay 1 to 3 nests per season with 100 to 110 eggs per nest. These nests will incubate for approximately 2 months before hatching. The most well-known nesting sites for the olive ridley are located on the coasts of Costa Rica, Mexico, and India. It is estimated that there are approximately 800,000 nesting females in the population.
Conservation and Specific Human Impacts: Threats that are specific to the olive ridley include poaching of eggs, loss of nesting habitat, and becoming bycatch in commercial fishing trawls. In order to protect olive ridleys, Mexico monitors and protects their nesting beaches. Mexico also established 17 reserve areas in 1986 and passed a law in 1990 to prevent egg poaching. Due to becoming bycatch in commercial fishing trawls, turtle excluder devices (TED’s) are now required on trawls in the U.S. and Mexico to reduce the accidental catch of these turtles. Because of these regulations, populations of olive ridleys in the waters of Mexico have stabilized. Take and bycatch from trawl nets remains a concern in the western Atlantic and Indian Oceans (United States Fish and Wildlife Service, n.d.).
Citations:
Abreu-Grobois, A & Plotkin, P. (IUCN SSC Marine Turtle Specialist Group). 2008. Lepidochelys olivacea. The IUCN Red List of Threatened Species 2008: e.T11534A3292503.
https://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T11534A3292503.en. Downloaded on 03 March 2021.
NOAA Fisheries. (n.d.). Olive Ridley Turtle. https://www.fisheries.noaa.gov/species/olive-ridley-turtle
US Fish and Wildlife Service: North Florida Ecological Services Office. (n.d.). Olive Ridley Sea Turtle (Lepidochelys olivacea).
https://www.fws.gov/northflorida/seaturtles/turtle%20factsheets/olive-ridley-sea-turtle.htm