Find Nesting Sea Turtles in Costa Rica

I would not have guessed it, but there’s something mystical about nesting sea turtles (or arribadas) in Costa Rica. Somewhere in my distant past I heard about them coming ashore in droves to lay eggs. I never expected to personally bear witness to the phenomenon, though!

Great Timing

They say timing is everything. That was certainly true during my second visit to Costa Rica. I was on a home exchange in Playa del Coco and overheard locals talking about an arribada, or arrival. The term refers to the mass nesting of sea turtles, and it sounded like one was imminent. I figured I’d better seize the opportunity. (Explorative travel!) 

Let me pause here to acknowledge the people who made it possible for me to eavesdrop in a second language. My childhood neighbor, Señor Bent, gave me weekend Spanish lessons and the foundation to become fluent. Ms. Serafini spurred me further along in middle school, followed by a fine assortment of Spanish teachers in high school and college. Without them and the gift of a second language, my travels would have been far less meaningful. And I would have missed the arribada.  

Playa Ostional on the Nicoya Peninsula

It was November— in the midst of the rainy season and the turtles’ prime nesting period. It was also the off season for tourism, and specialty activities were harder to arrange. After scouring local websites, I knew what to ask for. Transportation to Playa Ostional and an authorized guide to take me into the protected nesting area. In this instance we were talking about Olive Ridley sea turtles.  

Arribadas

Nobody is quite sure what triggers the sea turtles to come ashore and lay their eggs en masse. They usually nest individually and throughout the year, almost always at the beach where they were born. But for some reason, Playa Ostional is the recurring site of arribadas. They seem to happen mostly from August to December, during the week preceding a full moon, and at high tide. These mass events nonetheless remain highly unpredictable.  

Arribadas involve hundreds, even thousands, of turtles over the course of 4-5 days. The mothers usually begin the slow, hard ascent up the beach at dusk. They use their rear flippers to dig a hole and lay about 100 eggs apiece. Then they drag themselves back across the beach and return to the sea. If all goes well, the eggs hatch about 7 weeks later around dawn, and the babies scurry to the water.  

Note that each species of sea turtle tends to have its own preferred nesting areas. Costa Rica’s beaches also host leatherback, green, and hawksbill turtles.  

Threats to Sea Turtle Survival

The eggs and hatchlings of the Olive Ridley turtles face numerous predators on shore. In the water, the babies remain easy prey. But a single arribada can produce millions of eggs. At first glance, those seem like pretty good odds. 

Yet despite being the most common sea turtles in the world, Olive Ridleys are in decline. They are considered endangered due to the destruction or contamination of their nesting sites.  

Ironically, arribadas themselves are so large that later-arriving turtles inadvertently destroy earlier nests. For that reason, Costa Rica permits the controlled harvesting of turtle eggs in the first month of peak nesting season.

Arranging to See an Arribada

Once I knew what to ask for, I reached out to local tourist agencies. I was lucky to connect with Amy of Avispas Adventures. She took me and a small group of fellow adventurers on the roughly 2.5-hour drive from Playa del Coco to Ostional. We rode in a comfortable, air-conditioned van and stopped several times for snacks and to use the restroom.  

Throughout the journey, Amy and her colleague educated us about the turtles and their nesting habits. I was glad to see the importance they placed on respecting and protecting the animals. We were advised to wear dark clothes and refrain from flash photography, since bright colors and light irritate the turtles. Our guides also ensured we kept an appropriate distance from the mothers.  

Still, we were allowed plenty of time to observe, walk the length of the beach, and take photos. It was a laidback, informative, and fascinating experience. Nature is remarkable, and seeing the arribada in person had a wholly unexpected, almost spiritual effect.  

Tailor Your Search

You have several options in Costa Rica for seeing an arribada yourself. It all depends on your location and the timing of your visit, so do a little bit of sleuthing online. And if you get the chance, take it!  

Already in the country? Read my post about the easiest place to spot wildlife in Costa Rica. Are you interested in volunteering to protect sea turtles (or a similar project) in exchange for free room and board? Click here!