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THE OSTIONAL NATIONAL WILDLIFE REFUGE IN COSTA RICA

About the Ostional Refuge: Where and what is this sea turtle sanctuary?

The Ostional National Wildlife Refuge was established in 1983 with the primary mission as the conservation of sea turtles and the protection of their reproductive habitat. The Refuge extends 15 km along the shoreline, including the beaches of Ostional, Nosara, Pelada, and Guiones on the Guanacaste peninsula. It covers 200 m of coastline, also extending inland along estuaries and mangroves and including 3 nautical miles of marine protected area.

 

Ostional is one of the most important sites for the olive ridley sea turtle in the world, second only to Escobilla, Mexico. This site is one of few in the world to host the mass-nesting behavior, known as arribadas, a phenomenon considered one of the most amazing wonders of nature. During arribadas, tens and sometimes hundreds of thousands of sea turtles come ashore to nest simultaneously over a period of several days. Ostional hosts the highest frequency of mass-nesting events and densest concentration of olive ridley sea turtles on Earth. 

 

Additionally, the Ostional National Wildlife Refuge protects important habitat for a diversity of coastal and marine flora and fauna, including mangrove and rocky intertidal ecosystems, with connectivity through the Rio Nosara Biological Corridor to Parque Nacional Barra Honda and Parque Nacional Diría.


THE RNVSO AREA MAP
View the Ostional National Wildlife Refuge Marine and Terrestrial Protected Area (RNVSO) ArcGIS overview and map viewer.
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MORE INFORMATION

[ + ] Learn more about arribadas

[ + ] Arribada & Tours FAQ

THE EGG HARVEST PROGRAM

About the Ostional Egg Harvest Program

Ostional is the only beach in the world where a legal harvest and commercialization of sea turtle eggs exists. The take of eggs was justified by scientific studies which found a large percentage of nests are destroyed by subsequently nesting turtles during the arribada. The high density of nests and large quantity of broken eggs also promote microbial growth and conditions which negatively impact embryonic development and causes low hatching success.

Therefore, in 1987 the government of Costa Rica established a law that allows the community of Ostional to harvest a small percentage of the eggs laid during the first three days of the arribada. In return, the Asociación de Desarrollo Integral de Ostional (ADIO) is responsible for protecting the turtles, cleaning debris from the beach, and patrolling day and night for poachers.

Learn More

Campbell, L. M. (1998). Use them or lose them? Conservation and the consumptive use of marine turtle eggs at Ostional, Costa Rica. Environmental Conservation, 25 (4), 305–319.
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Campbell, L. (2007). Sustainability of community-based conservation: Sea turtle egg harvesting in Ostional (Costa Rica) ten years later. Environmental Conservation, 34 (2): 122–131.
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Valverde, R. A., Orrego, C. M., Tordoir, M. T., Gomez, F. M., Solis, D. S., Hernandez, R. A., Spotila, J. R. (2012). Olive ridley mass nesting ecology and egg harvest at Ostional Beach, Costa Rica. Chelonian Conservation and Biology, 11 (1), 1–11.  
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Ostional National Wildlife Refuge Administration

The team of park rangers at the Ostional National Wildlife Refuge are an essential asset to the protection and conservation of this important habitat.

Ostional National Wildlife Refuge contact info

Phone: (+506) 2682-0400  •  (+506) 2682-0937
Follow the Refuge on Facebook:
Refugio Nacional de Vida Silvestre de Ostional

Ostional National Wildlife Refuge Park Rangers

Download the Ostional National Wildlife Refuge Guide

SEA TURTLES AT THE
OSTIONAL NATIONAL
WILDLIFE REFUGE
Three species of protected sea turtles nest at the Ostional National Wildlife Refuge: the olive ridley (Lepidochelys olivacea), Pacific green (Chelonia mydas agassizii), and leatherback (Dermochelys coriacea) sea turtle. Of the three sea turtle species, olive ridley sea turtles are the most abundant at the Ostional National Wildlife Refuge in Costa Rica. 
OLIVE RIDLEY
SEA TURTLES

The olive ridley sea turtle (Lepidochelys olivacea), also known as the Pacific ridley sea turtle, is a species of turtle in the family Cheloniidae. The species is the second smallest and most abundant of all sea turtles in the world. Lepidochelys olivacea is found in warm and tropical waters, primarily in the Pacific and Indian Oceans, but also in the warm waters of the Atlantic Ocean. This turtle and the related Kemps ridley turtle are best known for their unique mass nesting called arribada, where thousands of females come together on the same beach to lay eggs.

PACIFIC GREEN
SEA TURTLES

The green sea turtle (Chelonia mydas), also known as the green turtle, black (sea) turtle or Pacific green turtle, is a species of large sea turtle of the family Cheloniidae. It is the only species in the genus Chelonia. Its range extends throughout tropical and subtropical seas around the world, with two distinct populations in the Atlantic and Pacific Oceans, but it is also found in the Indian Ocean. The name refers to the usually green fat found beneath its carapace, not to the color of its carapace, which is olive to black.

LEATHERBACK
SEA TURTLES

The leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle or leathery turtle or simply the luth, is the largest of all living turtles and is the fourth-heaviest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys and family Dermochelyidae. It can easily be differentiated from other modern sea turtles by its lack of a bony shell, hence the name. Instead, its carapace is covered by skin and oily flesh.

THE OSTIONAL NATIONAL WILDLIFE REFUGE’S FLORA AND FAUNA
Within the Ostional National Wildlife Refuge, sightings of sea turtles, howler monkeys, white-nosed coatis, elegant trogons, and turquoise browed mot-mot are all common sights. Sightings of whales, dolphins, whale sharks, manta rays, tamanduas, jaguarundis, ocelots, kinkajous, and aracaris are not uncommon.

View our project on iNaturalist for a full list of species within the Ostional National Wildlife Refuge and surrounding area from observations submitted by community members and visitors.
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WILDLIFE CONSERVATION ASSOCIATION

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