Exploring Ostional Wildlife Refuge: a guide to Costa Rica’s turtle haven
- Esteban Acedo
- Aug 21, 2024
- 7 min read
Updated: Sep 18, 2025
In the pitch-black night, with only the moonlight illuminating the ocean waves, imagine witnessing a marvel of nature or even being a part of it in a meaningful way. That is exactly what the Ostional Wildlife Refuge offers. During the rainy season, up to hundreds of thousands of sea turtles populate a rare 15 km long strip of beach, where they lay their eggs in the volcanic black sand. This is one of the highlights of Guanacaste and a must-visit for any nature lovers in Costa Rica!
This blog post will highlight everything you need to make the most out of your trip! From how to get to the refuge, to what time is best for seeing the turtles! Gear up to witness a wonder of Planet Earth!
In this blog post, we will highlight the following:
The History of the Ostional Wildlife Refuge:
Established in 1983, the Ostional Wildlife Refuge was created to protect the nesting grounds of the Olive Ridley sea turtle. Ostional beach is uniquely known as the only beach in the world where harvesting turtle eggs is legal. A tragic reality was discovered early on, as scientists observed that the eggs laid by the first wave of nesting turtles were often destroyed by subsequent turtles arriving to lay their eggs.
In response, the Costa Rican government agreed with the community of Ostional in 1987. This agreement allowed the community to harvest the eggs laid during the first three days of nesting, which were likely to be destroyed anyway. In return, the Asociación de Desarrollo Integral de Ostional (ADIO) committed to protecting the turtles, patrolling the beach to prevent poaching, and keeping the area clean and free of debris.
Marine Turtles at Ostional
There are three species of Turtles Found at Ostional. They include:
Olive Ridley Turtles: The most common visitors, known for their synchronized mass nesting events called arribadas.
Leatherback Turtles: The largest sea turtles, which nest sporadically throughout the year.
Green Turtles: Although less frequent, they still make a significant contribution to the biodiversity of the refuge.
The Phenomenon of "Arribada"
The beaches of Playa Ostional, Playa Nosara, and Playa Guiones are where these turtles come ashore every year to nest and lay their eggs between the rainy months of July and December. This phenomenon is known as "arribadas" and it takes place from 4 to 10 times during this period, lasting between 3 to 10 days each. Female Olive Ridley sea turtles deposit between 80 to 100 white, delicate eggs each time, and then return to the sea. However, despite over 10 million eggs being laid, only a fraction survive. The largest “arribada” recorded in Ostional occurred in November 1995, when nearly 500,000 turtles arrived at once.
During this process, the normally shy sea turtles are unconcerned about any disturbance. “Bumping into each other, crawling over each other, they are automatons on their way to fulfill a predetermined task: lay their eggs at all cost,” is their state according to Costa Rica National Park Service information.
When is the best time to visit Ostional Wildlife Refuge?
The ideal time to visit Ostional Wildlife Refuge is during the rainy season, which spans from May to December. During this period, turtles can be seen almost daily, even outside of the mass nesting events known as "arribadas". The most intense "arribadas" occur from September to December, with smaller ones sometimes happening in June and January. While turtles nest year-round, sightings during the dry season months from February to April are rare, with potentially only one or two turtles per night.
Turtles prefer to nest in the dark, making the waxing crescent moon or the period just after the new moon the optimal times for observation. The best times to see turtles in Ostional are around sunset, approximately 5 PM, and early in the morning, around 5 AM. Baby turtles frequently hatch in the early morning hours.
Volunteer opportunities at Ostional Wildlife Refuge
Numerous conservation projects welcome volunteers. Organizations like WorkingAbroad, Fundecodes and Panda.org can be visited for such opportunities. Activities include monitoring nests, assisting hatchlings, and beach cleanups. These efforts are crucial for maintaining the refuge's health and success. Those interested in volunteering may contact the offices of the Ostional Wildlife Refuge directly. Another good place to start is at Costa Rica's National Parks website where they have their own volunteer program.
Ostional Wildlife Refuge offices: (506) 2682-0400
Association ASVO: (506) 8843-2324/ 2258-4430/ 2233-4430/2233-4989.
Flora and Fauna
While turtles are the main attraction, Ostional is home to a variety of other wildlife. Birdwatchers can spot species like pelicans and frigate-birds. The coastal vegetation, including mangroves and tropical forests, supports diverse plant and animal life, making the refuge a rich ecosystem to explore. Sightings of dolphins, sea turtles, howler monkeys, coati mundis, violaceous trogons, magpie jays, and turquoise-browed mot-mot are all common sights.
Conservation efforts
Ostional's conservation success is a collaborative effort involving local communities, international organizations, and government agencies. Sustainable practices, such as regulated egg harvesting, ensure that conservation benefits extend to the local economy. Despite successes, challenges like climate change and illegal poaching persist, requiring ongoing vigilance and support.
Location and Directions
The Ostional Wildlife Refuge is situated on the Nicoya Peninsula, approximately 50 km (31 miles) from Nicoya city and a few kilometers (a couple of miles) from Nosara. It is 107 km (66.5 miles) and a 2.5-hour drive from Playas del Coco, 60 km (37.6 miles) and a 1.5-hour drive from Tamarindo, and 104 km (64 miles) and a 2-hour and 15-minute drive from Liberia Airport.
If you plan to drive yourself, it's best to have a 4WD or a high-clearance car for this route.
Bus:
From Santa Cruz, take the bus departing at noon to Ostional, which returns at 5:00 PM.
From San Jose: take a bus to Nosara, which leaves at 5:30 AM, and from Nosara take a taxi to Ostional.
From Nosara: Catch a local bus headed north, up the coast toward San Juanillo or Playa Azul. Or take a fairly priced taxi.
Guidelines for visiting Ostional Wildlife Refuge
Mandatory Guided Tours
It is crucial to visit the refuge with a guide. Attempting to enter on your own will result in being stopped by the rangers.
Appropriate Attire
When participating in a tour, wear black clothing. Turtles are extremely sensitive to light and bright colors. They often check the beach from the waves to determine if it's safe to nest. Bright colors or white light can deter them from coming ashore.
Light Restrictions
Avoid using flash photography and white light. Guides will provide or use red lights, which are not harmful to the turtles. Always use red light when taking pictures.
Respectful Distance
Please refrain from touching the turtles and maintain a respectful distance from those that are nesting. It’s important to give them space.
Assisting Hatchlings
If you encounter baby turtles, you can assist them by scaring away predators such as vultures and dogs. However, do not touch or pick up the hatchlings. They need to feel the sand to imprint the location, as female turtles will return to the same beach to nest when they reach adulthood.
Conclusion
Ostional Wildlife Refuge is a must-visit for anyone passionate about marine conservation and natural wonders. You are not only helping protect these wondrous yet endangered creatures but are also witnessing a marvel. A once-in-a-lifetime experience indeed!
Frequently asked questions
When can you see turtles in Ostional?
Sea turtles nest in Ostional year-round, but the most famous events are the arribadas—mass nesting arrivals of thousands of olive ridley turtles. These typically happen once a month, often around the last quarter moon. The biggest arribadas occur during the rainy season (July–December).
How much does it cost to go to Ostional National Wildlife Refuge?
Entrance to the refuge costs around $10 USD per person for foreigners and a smaller fee for Costa Rican residents. You must be accompanied by a certified local guide to enter during turtle nesting events.
Where to see baby turtles in Costa Rica?
Baby turtles (hatchlings) can be seen on protected beaches like Ostional, Tortuguero, and Playa Grande. At Ostional, you can witness baby turtles making their first journey to the ocean, usually a few weeks after an arribada.
Where can I see turtles in Nosara?
The best spot is Playa Ostional, just 20 minutes north of Nosara. This is one of the most important turtle nesting beaches in the world.
How do I get to Ostional?
Ostional is about a 20–25 minute drive north of Nosara. The road is unpaved and can be bumpy, especially in the rainy season, so a 4x4 vehicle is recommended. From Liberia Airport, the drive is about 2.5–3 hours.
Are national parks free in Costa Rica?
No, most national parks and wildlife refuges in Costa Rica charge an entrance fee. Prices range from $5–$20 USD for foreigners, depending on the park.
What is the best month to see turtles in Costa Rica?
You can see turtles year-round, but the peak nesting season is July to December. In Ostional, massive arribadas usually happen during these months. Tortuguero has its own nesting seasons for green turtles (July–October).
Where to see sloths in Costa Rica?
Sloths are not commonly found in Ostional, but you can easily spot them in places like Manuel Antonio National Park, Cahuita, Tortuguero, and La Fortuna.
Can you swim with turtles in Costa Rica?
No, swimming with turtles is not allowed in Costa Rica, as it can disturb and harm them. The best way to see turtles is by visiting nesting beaches with certified guides or snorkeling responsibly in designated marine parks where sea turtles live.
How to see turtles in Tortuguero?
In Tortuguero, turtle tours are strictly regulated. You must go with a licensed guide at night to watch nesting turtles (mainly July–October for green turtles). Tours usually last 2–3 hours and allow you to witness this unique spectacle without disturbing the animals.
What to do in Nosara, Costa Rica?
Nosara is known for surfing, yoga retreats, wellness centers, beaches, wildlife watching, and turtle tours at Ostional. It’s also a great place to enjoy healthy restaurants and eco-friendly accommodations.
What is the meaning of arribada?
Arribada means “arrival” in Spanish. In Costa Rica, it refers to the incredible phenomenon when thousands of olive ridley turtles come ashore at once to nest—one of nature’s most amazing spectacles, and Ostional is one of the very few places in the world where it happens regularly.