On today’s edition of SUFB Species Tuesdays, we highlight the olive ridley sea turtle. This close relative of the Kemp’s ridley is the most abundant of all sea turtle species, with an estimate 800,000 adult females in existence. They’re also the smallest sea turtle, typically measuring between 0.6 and 0.75 meters in length. They’re named for the olive coloration of their shell, which transitions from dark gray to olive green as turtles reach adulthood.
Olive ridleys inhabit warm to tropical waters throughout the globe, though are most commonly found in the Pacific and Indian oceans. They spend most of their life in solitude, though females come ashore in huge numbers to lay their eggs during the breeding season (June – December). These nesting events are called arribadas, which is Spanish for “arrival.” Olive ridley females return to the exact same site at which they hatched to lay their own eggs, and can lay up to three clutches per year. Though it’s not well understood how olive ridleys coordinate these arribadas, it’s thought that they coincide with certain weather events, such as specific wind patterns or moon cycles.
This sea turtle species feeds primarily on jellyfish and small invertebrates like crab, shrimp, and snails. They’ve also been known to feed on algae and seaweed from time to time. Juveniles and hatchlings are prey for small mammals, birds, and reptiles. Sharks and killer whales occasionally prey upon adult Olive ridleys, though humans pose the largest threat to this species.
The olive ridley sea turtles is listed as “vulnerable” by the IUCN, though because there are only a few nesting sites worldwide they are extremely susceptible to mass mortality events. The eastern Pacific olive ridley population, which nests on the west coast of Mexico, is listed as endangered. Historically these turtles have been hunted and killed for meat and leather. Though they receive more protection today, olive ridleys are still threatened by fishing vessels that do not utilize turtle-exclusion devices, poachers, and pollution. Many olive ridley foraging areas are contaminated with anthropogenic pollutants, including agricultural runoff and discarded plastics. Unfortunately, many individuals are not reaching their average natural lifespan of 50 years.
Despite the recovery that olive ridley sea turtles have seen over the past few decades, they’re still highly susceptible to population declines and potential extinction. The good news is there are a variety of ways you can help protect this charismatic species. There are plenty of sea turtle rehabilitation facilities that search and care for injured individuals. By donating what you can to these organizations you can contribute to their efforts from anywhere on earth. If you live near a coast or an area with local sea turtle populations, you can become a wildlife monitor or participate in beach cleaning efforts. You can also support research projects domstically and internationally that seek to gain a better understanding of olive ridley nesting events and their life cycle. Finally, by cutting down on the amount of plastic products you consume you can help reduce the pollution that washes off into our oceans and injures or kills olive ridley sea turtles.
Enjoy the Podcast!