While the coastal region of Playa Grande is part of the Las Baulas National Marine Park, which is supposed to be a prime leatherback sea turtle beach, it is very rare that you will actually see any turtles here. Unfortunately, due to offshore longline and net fishing and other negative human impacts, the sea turtles of Playa Grande are nearly non-existent. Measures are being taken to protect the sea turtles if and when they do come ashore to nest, but it is nearly impossible to eliminate the threat they face far offshore and out of the national park’s jurisdiction.
Leatherback sea turtles, the largest of all of the species of sea turtles, are also the most endangered. Costa Rica is home to several other species though, including the most common Olive Ridley sea turtle. During the rainy season months, this sizable species of sea turtle returns to one of two beaches in Guanacaste in massive numbers. The mass arrival of sea turtles is called an arribada.
The most accessible location to witness this incredible phenomenon is on Playa Ostional just to the south before Nosara. Between July and November, once and sometimes twice a month, thousands of mama Olive Ridley sea turtles come ashore between dus and dawn to lay their eggs. The arribadas are coordinated around the new moon when the nights are the darkest and the tides are the smallest.
Ostional is a protected wildlife refuge and it is illegal to be on the beach there during an arribada without a certified guide. However, it is easy to find one once you arrive there or you can make a reservation prior to driving down. You can also have the RipJack Inn concierge set up a tour and transportation for you if you don’t want to drive yourself there, which can be a bit daunting if you aren’t used to driving at night in Costa Rica.
I recommend arriving right before the first break of day, which is usually around 5AM. Night tours are more popular but having the daylight on your side makes the experience even more magical. Seeing thousands of sea turtles crawling up the beach, digging their nests, laying their eggs, and heading back out to sea is an experience unmatched by any other. The turtles that come ashore in Ostional to lay their eggs where once born there themselves.
You can stay up-to-date with the arribadas through the Association of Local Guides in Ostional by following them on Facebook: https://www.facebook.com/GUIASAGLO/
If the timing works out and you are here near a new moon between July and November, don’t miss out on an arribada!