The Cambrian

Large sea turtle surfaces at San Simeon Cove

This olive ridley turtle was sighted last week in San Simeon Cove.
This olive ridley turtle was sighted last week in San Simeon Cove. Special to The Cambrian

While kayaking in San Simeon Cove last week, kayak business owner and guide Cubby Cashen spotted an unusual visitor in the kelp beds south of the pier: a sea turtle measuring approximately 3 feet in diameter. Using pictures and a video of the turtle, biologist Jeffrey Seminoff of NOAA’s Southwest Fisheries Science Center (SWFSC) identified the animal as an Eastern Pacific olive ridley turtle (Lepidochelys olivacea), an uncommon visitor to the area. 

The species is well known in the eastern tropical Pacific to the south, but the distribution along the U.S. West Coast is less understood. According to SWFSC biologist Scott Benson, “there has been an increase of marine turtle sightings across the entire West Coast of North America during the past year, likely linked to elevated sea surface temperatures, and several turtles have been reported as far north as British Columbia.”

Weighing approximately 100 pounds, the olive ridley is omnivorous and usually seen in the open ocean, although it is also known to inhabit coastal areas, including bays and estuaries. Olive ridleys can dive to depths of about 500 feet to forage on invertebrates on the ocean bottom. 

Olive ridleys commonly nest in successive years and migrate long distances between foraging areas in the open ocean and coastal breeding and nesting grounds in Central America. Ships crossing the Pacific have seen olive ridleys more than 2,400 miles from shore.

Eastern Pacific populations breed on the Pacific coast of Central America. The olive ridley has one of the most extraordinary nesting habits in the natural world. Large groups of turtles gather off nesting beaches before coming to shore in vast numbers all at once, a phenomenon known as an “arribada.” During these arribadas, hundreds to thousands of females come ashore to lay their eggs. At many nesting beaches, the turtles nest so densely that previously laid egg clutches are sometimes dug up by other females excavating a nest for their own eggs.

Unfortunately, this nesting behavior makes it easy for people to harvest adult turtles and/or eggs, which is one of the reasons that many sea turtle species in U.S. waters are listed under the Endangered Species Act. Other threats to sea turtles include entanglement in fishing gear and marine debris, pollution and loss of nesting habitat.

Reporting on turtles

Sightings and strandings of marine turtles provide valuable insight into the distribution, life history, threats and geographic range of sea turtles along the U.S. West Coast. If you see a turtle, please do not touch or disturb it, but please do report it to SWFSC.Turtle-sightings@noaa.gov. Include as much information as possible, including the date of the observation, approximate location including latitude and longitude if available, approximate size of the carapace (shell), behavior of the animal (swimming, lethargic, responsive etc.), condition of the animal (e.g. carapace covered in algae etc.), and photos. 

If you encounter an injured or beached sea turtle that appears to be stranded, please report it to the West Coast Stranding Network at 1-866-767-6114.

For more information on NOAA Fisheries sea turtle research, visit the SWFSC’s Marine Turtle Research Program website at http://go.usa.gov/3rxV3.

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