Contribution starting at $2,450
Exported from Streamline App (
9 days (avg. $272 a day) Includes accommodations, food, and all related research costs
Ocean Health

Marine Mammals and Predators in Costa Rica

Golfo Dulce, Costa Rica Map it
Activity Level
Shared meals
Special diets accommodated
Staff-prepared meals


This Earthwatch project has added safety measures to allow for responsible fielding of volunteers and field staff at this time.


This project has added safety measures to allow for responsible fielding of volunteers and field staff at this time.

Those measures include

  • Proof of vaccination requirement
  • Decreased overall team size to allow for physical distancing
  • Face mask requirements
  • Single accommodations
  • Adjusted transportation arrangements
  • Increased cleaning and sanitization

When reading the Online Expedition Briefing, please keep these adjustments in mind.

whale in costa rica
volunteers on a boat in costa rica
ocean view in costa rica
dolphins and marine mammals of costa rica
study dolphins off costa rica
earthwatch volunteers observe dolphins and other marine mammals
costa rica
whale in costa rica
volunteers on a boat in costa rica
ocean view in costa rica
dolphins and marine mammals of costa rica
study dolphins off costa rica
earthwatch volunteers observe dolphins and other marine mammals
costa rica

Join researchers in the pristine wilds of Costa Rica to conduct critical research on marine mammals and predators. Your findings may help to develop a permanent marine protected area.

Earthwatch volunteers in costa rica

Golfo Dulce, a narrow inlet on the southern Pacific coast of Costa Rica, provides a rich habitat for cetaceans (whales and dolphins). It remains fairly pristine, since the many tourists who visit Costa Rica each year haven’t quite discovered it yet—which makes now a crucial time to investigate what the ecosystem needs to remain healthy. By understanding the behavior and tracking the abundance of the marine mammals and predators in this region, we can ensure we have the information needed to best protect them when tourism starts in earnest in this beautiful, wild place.

For about a decade, this project has gathered information on three species of cetacean in the gulf: the pantropical spotted dolphin, the bottlenose dolphin, and the humpback whale. In studying these cetacean species, researchers hope to understand how to preserve the entirety of this beautiful marine ecosystem.

This project is now entering a new stage and will be expanding to understand of how the entire Golfo Dulce ecosystem functions by gathering data of the presence of other top predators, including sharks.

Through this research, and with your volunteer involvement, this project will help to develop conservation plans to protect the marine biodiversity in the gulf in the future.



A Typical Itinerary

  • DAY 1   Arrival, orientation, training
  • DAY 2   Training on dolphin and whale behavior sampling and dolphin photo-identification
  • DAYS 3-5   Dolphin surveys, whale surveys, photo-ID work
  • DAYS 6-8   Trophic web work, fishing surveys (for sharks)
  • DAY 9   Departure




In this beautiful tropical setting, you will:


monitor whales and dolphins
Monitor whales and dolphins, and photo-identify individuals

By boat, you will follow groups of dolphins and whales. When someone spots a cetacean, you'll document its GPS location, size, and behavior (e.g., feeding, traveling). Back on land, you’ll help sort pictures of each dolphin species so that scientists can identify individuals using the unique scars, notches and other markings on their dorsal fins. The researchers know the dolphins in the gulf especially well, so expect to hear stories about some of their most memorable encounters.

record trophic web data
Record trophic web

Document and describe the species in multi-predator assemblages by observing aggregations of schooling fish and their predators, such as dolphins, seabirds, sharks, and rays.

conduct fishing surveys
Conduct fishing surveys

Set long lines out by boat at dusk, returning to El Chontol for dinner. After dinner and once “fully dark," you’ll head back out on the boat to check the lines, identifying and measuring all sharks and other captures before releasing back into the gulf.


Field conditions and research needs can lead to changes in the itinerary and activities. We appreciate your cooperation and understanding.




4 Reviews on this Expedition

If you have been on this expedition, others considering attending would love to hear about your experience.
Rachel Wildman | September 12, 2017
This expedition was a fantastic, once in a lifetime experience! It was really interesting to learn about the potential impacts to the whales and dolphins in Golfo Dulce and how the work that Lenin and David are doing can help reduce that impact. I learned a lot about what they do as scientists and it was really great to feel like I was actually helping to further their research. They are very protective of these dolphins and whales and that was contagious for all of us. Going out on the boat to see the dolphins and whales up close was a highlight - I got a picture of a baby whale with his mouth open! So cute! Also, fishing with the long line was an unexpected fun activity - we caught a small tiger shark, inspected and measured it, then put it back. What other trip would you go on where you could do that?? This was an excellent trip! So glad I went.
Suzanne Thompson | September 10, 2017
I highly recommend this expedition. I loved every minute of it. David was very passionate about the whales and dolphins and Golfo Dulce. He loved sharing his knowledge of this project and how important the research is for the health of the animals and Golfo Dulce. The accommodations in the handcrafted eco-cabins were lovely and the home cooked food was delicious. I enjoyed spending my free time on the porch bird watching or playing cards with other team members.
Kenneth Dubuque | September 9, 2017
It was hot, wet work following whales and dolphins in a boat for hours in Golfo Dulce; not to mention catching fish and sharks, especially at night. But the reward of seeing magnificent humpbacks and spectacular bottlenose and spotted dolphins made it all worthwhile. The lectures and supplemental videos provided significant insight into understanding these creatures and their habitat, as well as the food chain and health of this environment. Our efforts hopefully will help this area to become a protected marine ecosystem. Lenin, the PI and David, his associate were very informative and patient in answering our many questions. The accommodations were more than adequate, the family owners and staff accommodating, the food terrific, the showers fairly warm,and there were no mosquitoes despite the plentiful rainfall (after all it is a rain forest). We also enjoyed a local school visit complete with ice cream and soccer, a visit to a wonderful wildlife sanctuary and lunch in the nearby town. Our great team had a lot of fun and more than a few laughs, sometimes even at my jokes. Thanks to all for another great adventure. I've already signed up for my tenth expedition. Ken Dubuque, 8/22/17 team

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