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Sea Turtle Research & Conservation Expedition in Costa Rica

For many years Rich Coast Diving has been supporting the work of local conservation efforts. It is part of our mission and core value as a business to educate our guests about sustainable diving practices and participate in local conservation work. January earlier this year we had the pleasure of hosting a very successful citizen science trip with Randall Randall Arauz.

During the week long event, we had about 25 participants that helped with identification, tagging and tissue sampling of sea turtles and eagle rays. An event that we are planning to organize twice every year. So if you are interested do not hesitate to contact us for more information.


Mission and vision statement Rich Coast Diving

1.Conservation activist Randall Arauz

In Costa Rica, sea turtle and shark biologist Dr. Randall Arauz is the most famous conservation activist. Randall Arauz is a prominent advocate for marine wildlife conservation in Latin America. He held the position of Central American Director at Turtle Island Restoration Network from 1997 to 2007. Arauz also established TIRN’s sister organization in Costa Rica, PRETOMA, and later CREMA. Additionally, he is a co-founder of MigraMar.

Arauz has received several prestigious awards for his environmental work, including the Goldman Environmental Prize for Central and South America in 2010, the Gottemburg Award for Sustainable Development in 2010, and the Whitley Fund for Nature Gold Award in 2006, among numerous other honors.


Currently, Randall is the Science and Development Consultant for the Endangered Marine Species Rescue Center of Costa Rica (CREMA-Costa Rica), a grassroots non-profit, and the International Marine Conservation Policy Advisor for Marine Watch International, a San Francisco California based non-profit.  Most of the field work is held in the Nicoya Peninsula, and Cocos Island National Park, Costa Rica.

Video: Randall Arauz and shark conservation status in Costa Rica

2.Sea Turtle Expedition in Costa Rica

One of the focus species of our conservation week are the sea turtles found in Costa Rica's Pacific Coastal waters. Sea turtles are one of the main groups that CREMA works with, operating 4 community-based nesting olive ridley sea turtle (Lepidochelys olivacea) conservation projects (San Miguel, Costa de Oro, Bejuco and Corozalito).  We also perform “in-water” monitoring of green (Chelonia mydas) and hawksbill (Eretmochelys imbricata) sea turtle populations.


During the sea turtle expedition, the guest divers are trained to safely assist on catching turtles during dive activities. Only the biologists are allowed to catch turtles, but the guests assist in bringing the turtle on-board and help with measurements. Sea turtles are brought on board for weighing and measuring. Randall and his team also obtain tissue samples for genetic and stable isotope analysis, and tag the sea turtle with external metal flipper tags.

Sea turtle tagging Costa Rica

Photo: Measuring hawksbill sea turtle carapace size


The science generated is used to foster the improvement of sea turtle conservation and management, such as by identifying critical and essential habitats for these species, identifying the threats, and calling on the authorities for the appropriate measures to be taken at these sites. 

Through Randall's sea turtle work two marine protected areas have been created in the Nicoya Peninsula, the Caletas National Wildlife Refuge (2006) and the Camaronal National Wildlife Refuge (2009). CREMA is also working with the Ministry of Environment on the creation of new marine protected areas, particularly considering the threat posed by a potential return of the shrimp trawl industry, banned since August of 2019.


With this expedition our intention is for your support to go beyond a sea turtle expedition. We need as many sea turtle advocates to support our work as possible for the science to influence public policy…that’s where the real trick is at!  Hopefully, after a week’s infusion into sea turtle biology and conservation, you’ll be an activist !


During this expedition the group also dived the Catalina Islands, an archipelago of over 20 Islands and rocky outcrops. The area is currently unprotected, and is heavily used by the dive tourism industry, the sports fishing industry, and the small-scale fisheries industry. Randall is working with local conservation groups for a protection status to be granted to the site. 


Catalinas Islands Costa Rica Drone photo

3.Sea turtle nesting in Costa Rica

Visiting sea turtle nesting grounds is one of the activities during our conservation week with Randall Arauz. And more specifically the leatherback, Olive Ridley and green turtles. The leatherback turtle is the largest living sea turtle. It is also a species that has rapidly declined in numbers mainly due to human influences. They grow to between 1.2 and 2.4 meters (4 and 8 feet) long and can weigh upwards of 360 kilograms (800 pounds).  The leatherback turtle has been cruising around the world’s oceans (Pacific, Atlantic and Indian Ocean) for more than 100 million years.

In Las Baulas National Marine Park in Playa Grande, where for thousands of years, the leatherback turtles that hatched in Playa Grande have returned to lay their eggs.

This 5 km stretch of beach is home to the 2nd largest nesting site for Leatherback sea turtles in the entire world, and these majestic creatures and their eggs are protected here by law. Leatherback turtles are the largest marine turtles in the world, weighing approximately 1200 pounds and almost 8 feet long, and one of the most endangered.

The area is home to the second largest nesting location in the world for leatherback turtles. Because of this, the area is heavily regulated to protect the habitat. Nesting seasons are typically between October and February.

National Marine Park Costa Rica

This time of the year is the season for critically endangered leatherback turtles and endangered green turtles. The main priority is to see nesting leatherback turtles, but of course this depends on luck as their numbers are in decline. Numbers of nesting leatherbacks at Las Baulas National Park has declined 98% during the last two decades.  Nowadays, even during the peak of nesting activity (late December – early January), not even a turtle a night shows up to nest. So we took the advice of the Park Rangers, went to see the green turtles nesting at Playa Nombre de Jesús, a nearby nesting beach.


Night tours are available through the Playa Grande MINAE headquarters between October 20 and February 15. You must contact the office at +506-2653-0470 ext. 101 no more than eight days before you want to visit. This is your best opportunity to see the leatherback turtles nesting here. 


Sea turtle mating Costa Rica

Olive Ridley Turtle nesting


The Olive Ridley sea turtle is one of the most abundant sea turtle species, as well as being one of the smaller ones. They typically only weigh between 34-45 kilograms (75-100 pounds). Olive Ridley sea turtles return to the same beach that they hatched from. In a few special places they nest in large masses called arribadas. The arribadas are timed with the tide and the moon cycle. Witnessing an Olive Ridley arribadas is an experience unmatched by any other.


The turtle nesting tour near Playa Samara through Viator is an excellent choice. If you go during the peak Olive Ridley nesting season, your guide will take you to Playa Ostional where you will have the opportunity to potentially witness an arribadas (September-October).

Want to know more about our conservation trips with Randall Arauz. Contact us at:

Rich Coast Diving

Mrs. Céline Monfort

WhatsApp +506 8610 0914

Rich Coast Diving Costa Rica Logo

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