Olive Ridley Turtle (Lepidochelys olivacea)

Status: needs expert review. A science reviewer should confirm the current IUCN assessment before approval. The olive ridley (Lepidochelys olivacea) is one of the smallest sea turtles and is famous for synchronized mass-nesting events called arribadas.

At a glance

Field	Value	Source
Scientific name	Lepidochelys olivacea	NOAA Fisheries
Guild	turtle	—
IUCN status	Vulnerable (global; 2008 assessment)	IUCN Red List
US ESA status	Endangered (Mexico's Pacific breeding populations) or Threatened (all others)	NOAA Fisheries
International trade	CITES Appendix I	CITES
Population trend	Decreasing (global)	IUCN Red List
Range	Tropical Atlantic, Pacific, and Indian Oceans	NOAA Fisheries

Identification

The olive ridley takes its name from the olive-green color of its heart-shaped carapace (NOAA Fisheries). It is among the smallest sea turtles: adults measure about 2–2.5 feet long and weigh up to roughly 100 pounds (NOAA Fisheries). The carapace bears 5 to 9 pairs of lateral (costal) scutes, often asymmetric — a useful distinguishing feature (NOAA Fisheries).

Ecology and behavior

Olive ridleys are omnivorous, taking algae, crustaceans, tunicates, and mollusks, and can dive to around 500 feet to forage on the bottom (NOAA Fisheries). The species is best known for the arribada: a synchronized mass-nesting event in which hundreds to thousands of females come ashore together over a few days (NOAA Fisheries). Lifespan is estimated at roughly 30–50 years, though it is not precisely known (NOAA Fisheries). Specific behavioral claims should be cited to published research and confirmed in review.

Conservation status and threats

The IUCN Red List assesses the olive ridley globally as Vulnerable (2008 assessment) with a decreasing population trend (IUCN Red List). In the United States, Mexico's Pacific breeding populations are listed as Endangered under the Endangered Species Act and all others as Threatened, and the species is on CITES Appendix I (NOAA Fisheries; CITES). NOAA Fisheries identifies bycatch in fishing gear, harvest of turtles and eggs, nesting-habitat loss, vessel strikes, marine debris ingestion, and climate-driven change as major threats. The concentration of nesting into a few arribada beaches is itself a vulnerability, because exploitation or disturbance at one site can affect a large share of the breeding population (IUCN). Report figures as the cited authorities state them; a reviewer should confirm specifics.

How to observe responsibly

This page does not provide approach guidance. Follow a reviewed observation guide and local regulations, which set minimum distances and nesting-season protections. Arribada beaches are exceptionally sensitive: large numbers of nesting females and eggs are concentrated in a few locations, so this page keeps strictly to regional granularity. Never disturb nesting females, hatchlings, or nests, and never use lights on nesting beaches — artificial light disorients hatchlings (ETHICS.md; NOAA Fisheries). Choose operators that keep their distance and never handle turtles.

How you can help

• Log sightings to a recognized citizen-science platform (see the iNaturalist dataset card).
• Support bycatch-reduction work (e.g. turtle excluder devices) through credible organizations such as the Olive Ridley Project.
• On nesting coasts, support lights-out and beach-protection programs, and reduce plastics that reach the ocean.