A 10-day liveaboard adventure to experience, view, and photograph the incredible marine biodiversity of Cocos Island, as well as participate in crucial shark and sea turtle migration research.

Schedule & Pricing

To book your adventure, select a date listed below and enter your information.

If you have any questions about our dive expeditions, Trip Leader Todd Steiner is happy to answer them. Todd can be reached at tsteiner@seaturtles.org or (415) 488-7652.

Upcoming Expeditions:

Fall 2024
August 27 - September 2024
Price: The trip is being organized by Randall Arauz and Marine Watch and payment is made directly through Marine Watch International. The trip leaves from Costa Rica on Aug. 27 and returns Sep. 6, 2024. The cost for a cabin berth is $7,080 (Double Occupancy) and includes the $555 National Park entrance fee.
Space Available on Upcoming Cocos Trip!!! This is a highlight trip of a lifetime! Join Turtle Island's Todd Steiner, and Randall Arauz on a shark tagging expedition to Cocos Island, Costa Rica, one of the most incredible underwater dive sites on the planet! The trip is being organized by Randall Arauz and Marine Watch and payment is made directly through Marine Watch International. The trip leaves from Costa Rica on Aug. 27 and returns Sep. 6, 2024. The cost for a cabin berth is $7,080 (Double Occupancy) and includes the $555 National Park entrance fee. we will spend 10 days at sea onboard the amazing SeaHunter, conducting 21 scuba dives to count and tag sharks.
Call (415) 488-7652
Spring 2023
May 23rd - June 2nd, 2023
Price: $6,600 USD + $550 USD National Park Fee
Vessel: Undersea Hunter’s Sea Hunter (115-foot modern liveaboard yacht)
Make a Reservation
Fall 2023
November 11st - November 21st, 2023
Price: $6,000 USD + $550 USD National Park Fee
Vessel: Aggressor Adventure’s Okeanos Aggressor II (120-foot modern liveaboard yacht)
Make a Reservation
Spring 2023
May 23rd - June 2nd, 2023
Price: $6,600 USD + $550 USD National Park Fee
Vessel: Undersea Hunter’s Sea Hunter (115-foot modern liveaboard yacht)
Make a Reservation
Fall 2023
November 11st - November 21st, 2023
Price: $6,000 USD + $550 USD National Park Fee
Vessel: Aggressor Adventure’s Okeanos Aggressor II (120-foot modern liveaboard yacht)
Make a Reservation

Pricing Includes:

  • Ground transportation
  • An 11-day/10-night cruise
  • Meals and non-alcoholic drinks
  • Divemaster service
  • Seven full days of action-packed diving with three dives per day
  • Nitrox fills, tanks and weights

Not Included:

  • Transportation to Costa Rica
  • Hotel in Costa Rica
  • Lunch on Day 1
  • Additional equipment you might need, not included in trip cost

Payment Procedure

A deposit of $700 is required in order to secure your reservation. Bookings are confirmed upon receipt of this deposit. We require payment of the remaining balance 60 days prior to your trip departure date. National park fees and all additional land tour arrangements are payable with the final balance.

Turtle Island Restoration Network is able to accept payment plans for upcoming expeditions. For more information on payment plans, please email info@seaturtles.org.

The Site

Located 530 kilometers southwest of Costa Rica’s mainland, Cocos Island National Park and World Heritage site is known worldwide as an ocean haven for spectacular sharks, rare sea turtles, whales and abundant marine wildlife. It is the only island in the tropical eastern Pacific with a tropical rainforest, and is home to large populations of scalloped hammerhead sharks, white tip reef sharks, and a number of endemic fish that occur nowhere else on the planet.

In the underwater world that surround Cocos Island, hammerheads are easily viewed at close range at “cleaning stations,” and inquisitive green sea turtles commonly approach our dive teams, offering fantastic photographic opportunities and more. Other regularly observed species include Galapagos sharks, black tip sharks, silky sharks, marbled rays, eagle rays and bottlenose dolphins. Whale sharks, the special treat of any diving expedition, are also occasionally observed. Endless schools of jacks also swarm the island.

In 1994, Jacques Cousteau described the volcanic park as “the most beautiful island in the world.” Cocos Island is said to have been the inspiration for works such as “Treasure Island” and “Jurassic Park” and it was recently named one of the best places to dive with sharks by CNN.

The Diving

Led by Turtle Island Restoration Network Founder and Director Todd Steiner, biologist and respected conservation leader, expedition participants will join three fantastic dives each day, enhanced through work with Turtle Island biologists to study sea turtles and sharks, diving among schooling hammerheads, several species of sea turtles, and schools of thousands of fish as they support conservation efforts directly at the site.

Most of the action is at 60-90 feet (18-27 meters), and most dives are between 60-130 feet (18-40 meters). The average temperature is 79°F to 84°F (26°C to 29°C), although it can be a few degrees lower under the occasional thermocline.

The Research

Dive participants will have the exclusive opportunity to assist Turtle Island Restoration Network with various levels of research depending on experience and specific goals of each research expedition that may include:

  • Retrieving, maintaining, and re-deploying acoustic receivers
  • Censusing sharks and rays
  • Providing photos for research and conservation work
  • Photo-documenting species and activities

Turtle Island Restoration Network has been studying and tracking sharks and turtles at Cocos Island for almost a decade. In that time, we have seen the threats to the Park’s unique biodiversity in the form of continued illegal fishing, but also an increase in the awareness of the need to protect the marine biodiversity of this World Heritage Site. Research conducted on Cocos Island Dive Expeditions for the past 10 years has set the basis for better protections at Cocos Island and for a protected swimway to save sharks, sea turtles, and other migratory animals as they swim throughout the region.

*Current regulations of Cocos Island National Park only allow permitted scientific researchers to tag sharks, but participants will be able to observe this activity. If you scientific credentials and are experienced with the use of pole spears or spear guns, it is sometime possible to have you added to the permit. Please let us know if you are experienced and interested well in advance of the expedition.

Dive Operator

The expedition will be supported by the experienced and well-known dive company Undersea Hunter Group, which has been operating expeditions to Cocos Island since 1990 or Aggressor Adventures. The UnderSea Hunter Group is committed to top-notch dive experiences, vessels and service, and has operated expeditions for National Geographic, Sylvia Earle, and many other world-renowned ocean explorers and conservationists. Click here to read about Undersea Hunter’s commitment to safety. Aggressor Adventures operates a fleet of dive vessels at various locales since 1984.

Participants will be divided into two dive groups which will each be under the supervision of an experienced Divemaster/Rescue Diver. Every evening, participants can enjoy engaging conservation lectures and socializing with fellow ocean lovers.


Dive participants will spend ten days aboard UnderSea Hunter’s newest vessel, the MV Argo, a beautiful 130-foot live-aboard dive vessel for up to 18 passengers and a crew of 14, where a comfortable and stylish lounge, dining area, and sun deck comprise the social areas. A well-equipped galley enables the ship’s chefs to prepare fresh, international level, four-star cuisine. Three, powerful, fumeless 24-foot skiffs serve as tender-boats.

The Argo sometimes carries a three-person submersible that may be available (at additional cost) for participants who wish to explore deep depths. To see amazing 360 degree views of Cocos Island, the Undersea Hunter vessel and underwater views from the DeepSea submersible, click here.


The following is a sample trip itinerary and is subject to change.

Arrival Day: Dive participants must arrive at least one day prior to the boat departure date. Upon arrival to San José, we can have transportation waiting for you for the cost of $10-20 or you can take a taxi to your hotel. There are always taxis available at the airport, and minivans for those of you who carry a lot of gear. We can also recommend and arrange accommodations for hotels in San José. Please note that we do not pick up from all San José hotels.  

The evening before boat departure, if not before, we will confirm your pick-up time the next day. The evening is at your leisure. Air transport, airport transfers, hotel nights and meals before and after the cruise are not included in the charter.  

Day 1: The following day, generally between 8am and 1pm, we will pick dive participants up from certain hotels and transfer everybody by bus to Puntarenas where you will board the vessel. The drive takes about 2.5 hours, and gives you a chance to view the lush forest and rich farmland of the region.  

Day 2: A travel day. There will be time to arrange dive gear and camera gear as well as enjoy the Pacific and the sunshine. In addition, the group of incredibly experienced divers can provide plenty of stories to pass the time. There are videos and the experience of the Captain and crew to help you get excited for the diving…as if you need them! In addition, you may take this time to take one of our technical diving courses, at no additional cost to you.  

Days 3 – 8: The next days are spent diving the pinnacles around the perimeter of Cocos Island. Divers usually average three dives per day at depths of 60-100 feet or more. Participants will have an opportunity to help tag sharks, deploy receivers and record data during dives. Seminars and talks are provided after dinners by Turtle Island Restoration Network staff.

Day 9: Enjoy the last three dives of the trip before cruising back to Costa Rica (and reality).

Day 10: A travel day to discuss the diving and to compare your adventures with fellow participants.

Day 11: Arrival at Puntarenas. Immediately after breakfast, you will be transported back to San José. We strongly recommend staying one more night on land before flying out, in case of any unforeseen delays.

Dive Requirements

The minimum required level of certification to dive at Cocos is Open Water. Divers must be experienced divers, with PADI or NAUI membership, and must have personal DAN insurance. Nitrox is available for certified divers, and certification is also available on the vessel. For more information about required certifications, please contact our trip leader Todd Steiner at tsteiner@seaturtles.org.

Trip Reviews

What an adventure! This is my second time to Cocos Island and this time even more amazing that the first time. Being involved with Ocean Conservation and having an opportunity to assist with the shark and turtle tagging was pure joy. I came on this trip not knowing anyone, and leaving with lifetime friends, beautiful pictures, and stories that I will be sharing back home.

Janet ThomasUnited States

The experience on the DeepSee was an eye opening trip! It is a unforgettable memory through our life. Felipe our pilot is very experienced, funny and knowledgeable; thus we enjoyed the ‘ride’ with him a lot. Especially the gliding mobula rays that played with us more than 10 minutes. DeepSee Rocks!

Pinky & Claus WieslochGermany

Great fun to join the PRETOMA & TIRN expedition for yet another trip. Fantastic as always. Wildlife underwater is great. Crew above water is equally wonderful.

Mike and Nonie SilverUnited States

It was splendid!! I felt very happy, and very safe. Great dive masters. Everything is thought through very carefully on this boat to make guests comfortable. Extremely efficient and hard working crew. Would definitely recommend this live aboard.

Bill WhitmarshUnited States

First class operation, as always!! The crew was outstanding – very professional, helpful and fun. This was the vacation of a lifetime, and I will definitely be coming back again next year.

Deborah KearneyUnited States

Another fantastic trip on the Argo – my third on the boat and fifth with the UnderSea Hunter family. The vis wasn’t as good on this trip as it’s been on past trips, but there were still sharks to be seen and turtles to be caught and tagged. The trip companions were fabulous, and the crew was outstanding as always. A big thanks to Rafa for keeping track of us while we were below the water – a welcome sight to surface to. Bryan and Yoyo were great dive masters and Javier was always smiling. I’ll be back.

MarkUnited States

Latest News

Unlock the opportunity of a lifetime with our Cocos Island Shark Tagging Research Expedition! Dive into thrilling adventures while contributing to vital marine conservation efforts. Join us for a unique journey of discovery and make a lasting impact on ocean ecosystems. Book your spot today!

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