Do you want to see marine turtles laying their eggs on a sandy beach, under the moonlight, surrounded by the sounds of the Pacific Ocean and tropical rain? If so, Costa Rica offers one of the most extraordinary wildlife spectacles on Earth—the mass nesting of Olive Ridley sea turtles at Ostional Beach.Located on the Pacific coast of Costa Rica, the Ostional Wildlife Refuge protects one of the most important nesting sites in the world for the Olive Ridley sea turtle, known locally as the “Lora”. This refuge is truly off the beaten path for tourists, yet it is one of the most unforgettable natural experiences Costa Rica has to offer.
What Makes Ostional So Special?
Ostional Wildlife Refuge is famous worldwide for a phenomenon known as the Arribada, a Spanish word meaning “arrival.” During an Arribada, hundreds of thousands of Olive Ridley turtles come ashore at the same time to lay their eggs.
This is not a daily or even weekly occurrence. It is a precisely timed natural event, guided by lunar cycles, tides, and instincts that scientists are still studying today. Only a handful of beaches on Earth experience Arribadas, and Ostional is one of the most important among them.
Meet the Olive Ridley Sea Turtle
The Olive Ridley sea turtle (Lepidochelys olivacea) is one of the smallest sea turtles, yet it plays a massive role in marine ecosystems. Named for the olive-green color of its shell, this turtle is both resilient and vulnerable.
In Costa Rica, the Olive Ridley is affectionately called the Lora turtle. Ostional Beach is one of its most vital nesting grounds, making the refuge crucial for the survival of the species.
The Arribada: A Once-in-a-Lifetime Experience
The best time of year to witness an Arribada is August through December, during Costa Rica’s rainy season, when rainfall is heaviest in this region. While turtles may nest at other times of the year, the largest Arribadas almost always occur during these months.
The Arribada typically begins at the start of the last quarter moon. Several days before the event, observant visitors may notice hundreds of turtles gathering offshore, swimming close to the beach as if waiting for a signal.
Then it happens.
In the late afternoon and early evening, turtles begin emerging from the ocean. Soon, thousands follow, climbing onto the sand, sometimes crawling over one another, driven by instinct. The nesting continues all night long, often until sunrise.
It is an emotional, awe-inspiring sight—one that reminds visitors how powerful and ancient nature truly is.
Egg Laying and Nesting Behavior
Once on land, the turtles begin digging nests in the sand using their powerful flippers. Each turtle lays approximately 80 to 120 eggs, carefully covering them before returning to the sea.
The beach becomes a living landscape—sand shifting, shells glistening under moonlight, and the rhythmic sounds of waves and rainfall. Despite the chaos of so many turtles arriving at once, the process is surprisingly organized.
Not all eggs survive, which is part of nature’s balance. Predators, tides, and environmental conditions play a role—but the sheer number of eggs laid during an Arribada ensures the survival of the species.
Where Is Ostional Wildlife Refuge Located?
Ostional Wildlife Refuge is located on the northwestern Pacific coast of Costa Rica, in the province of Guanacaste.
It can be reached by 4×4 vehicle only, as the roads are rugged, unpaved, and often muddy—especially during the rainy season.
How to Get There
- From Liberia International Airport:
Approximately 1.5 hours by car - From San José:
Around 4 hours, depending on road and weather conditions
You can access Ostional from:
- Nosara, or
- San Juanillo
⚠️ Important note: During periods of very heavy rainfall, beach access may be limited or temporarily impossible.
Why a 4×4 Vehicle Is Essential
Ostional is truly off the beaten path. The roads include:
- River crossings
- Deep mud during rainy season
- Loose gravel and sand
- Poorly maintained sections
A 4×4 vehicle is strongly recommended, especially if you plan to visit during peak Arribada months.
Rules for Visitors
Because Ostional is a protected wildlife refuge, strict rules are in place to ensure the safety of the turtles:
- Visitors must be accompanied by a certified local guide
- No flash photography
- No touching or disturbing turtles
- No white lights allowed at night
- Follow all instructions given by refuge staff
These rules help ensure that tourism does not interfere with the turtles’ nesting process.
Community Conservation and Sustainability
One of the most unique aspects of Ostional is that local communities are directly involved in conservation efforts. Under government regulation, locals are permitted to harvest a small percentage of early-laid eggs, which would otherwise be destroyed by later nesting turtles.
This program:
- Supports local livelihoods
- Encourages conservation rather than exploitation
- Helps fund protection of the refuge
It is considered a model of sustainable wildlife management worldwide.
More Than Just Turtles
The Ostional Wildlife Refuge is surrounded by beautiful natural scenery, including:
- Remote Pacific beaches
- Tropical dry forests
- Mangroves
- Abundant birdlife
- Howler monkeys and white-faced monkeys
If you love untouched nature, this area offers a raw and authentic Costa Rica experience far removed from crowded resorts.
Best Time to Visit
- Peak Arribada: August – December
- Rainfall: Heavy, especially September and October
- Temperature: Warm and humid year-round
You must be comfortable with rain, mud, and rustic conditions—but the reward is extraordinary.
Who Should Visit Ostional?
Ostional is ideal for:
- Nature lovers
- Wildlife photographers
- Eco-tourists
- Adventurous travelers
- Families wanting educational experiences
- Anyone seeking authentic Costa Rica
This is not a luxury destination—it is a raw, emotional, unforgettable wildlife encounter.
Plan Your Costa Rica Adventure
If you are planning a trip to Costa Rica and want to experience some of the most beautiful beaches, rainforests, and wildlife refuges, there are excellent resources available to help you plan.
At the top of the page, click on “Buy Our Video” to view a mini trailer of the full-length 58-minute travel adventure film, filmed by Ken Creed. His credits include “Alaska,” which was selected by the National Geographic Society for screening at its travel adventure film series at Constitution Hall in Washington, DC.
Final Thoughts
The Ostional Wildlife Refuge is not easy to reach—and that is exactly what makes it so special. This remote stretch of coastline offers one of the most dramatic wildlife events on the planet, where ancient instincts unfold beneath moonlit skies.
If you are willing to venture off the beaten path, embrace rain and rugged roads, and respect nature’s rhythms, Ostional will reward you with an experience you will never forget.
Seeing thousands of sea turtles arrive together to lay their eggs is not just a trip—it is a privilege, a reminder of the fragile beauty of our planet, and one of Costa Rica’s greatest natural treasures.