California Aquarium Prepares for Possible First Sea Turtle Hatch

The eggs may soon produce the first sea turtle hatchlings from nests recorded on California beaches. Two olive ridley turtles laid clutches in Orange County in September, and federal biologists moved the eggs to the Aquarium of the Pacific on September 29 as high tides threatened the nests.

Aquarium staff are keeping the 204 eggs in sand-filled coolers and monitoring their conditions with sensors and cameras. The species typically incubates for 45 to 60 days, but staff cannot yet tell whether the eggs are developing normally or are fertilized. The first clutch reaches 45 days on October 31; the second was laid three days later.

The nests were unexpected: olive ridleys generally nest in tropical regions, and the previous known northernmost nesting site was in Baja California Sur. A marine heat wave and strong El Niño have raised Southern California ocean temperatures, conditions that may help explain the turtles’ arrival.

If hatching begins, aquarium staff plan to keep the turtles in darkness until evening, when they can be released. Federal biologists will assess surf and currents and select a beach for the release, which will not be announced in advance to limit disturbance. Less than 1% of hatchlings typically survive to adulthood.