Hammerheads Sharks

2023 Expeditions Costa Rica!

Cocos – Island of the Sharks

July 22, 2023
Aug 06, 2023
Aug 30, 2023
11 Days / 10 Nights – $4,995*


Ocean & Rainforest Adventures

Aug 16, 2023
Aug 23, 2023
More dates coming!
8 Days / 7 Nights – $2,500*


Destination Overview

Cocos – Island of the Sharks

Join us this summer for an unforgettable adventure to Cocos, the Island of the Sharks. This 6,000-acre UNESCO World Heritage site is the only island with a tropical rainforest in the eastern Pacific. It holds great fascination for divers, as it serves as the first landmark encountered by the north equatorial countercurrent and acts as a confluence point for marine currents. This unique combination creates the perfect environment for large migratory pelagic species, including hammerhead and tiger sharks, as well as all the other critters that Cocos is famous for.

The diving will be led by our Captain Beto, formerly of the Okeanos Aggressor, who boasts 29 years of experience. He has personally hand-picked a crew of Cocos veterans to ensure an exceptional experience. Our trips take place during peak season when the density of hammerhead sharks is at its highest, giving you the best chance to encounter whale sharks, humpback whales, and much more.

Update – May 11th: We have gained permission from the Costa Rican authorities to use our 132-foot flagship, the Nautilus Explorer, on our Cocos Island and near-coastal ocean and rainforest adventures. Our beautiful ocean stabilized Explorer features 4 levels of accommodation, huge back deck and camera tables, separate dining room and salon with million-dollar views and of course a fresh water hot tub.


Peak Season Diving

Why summer trips? Because that’s known as the best time to visit, and August is the single most popular month.

Cocos Island is famous for being one of the hottest shark diving destinations in the world. The schooling scalloped hammerheads are legendary. In recent years, tiger sharks have become more common. Whitetip reef sharks and silkies, our favourite “puppies of the sea” are common. Other species regularly encountered include galapagos, blacktop, silvertip, as well as many species of rays, especially around the cleaning stations. It’s easy to get lost in mesmerizing giant schools of big eyed jacks and mutton snapper.

“The rainy season” is from June through December, when the deep ocean upwellings attract manta rays and whale sharks can sometimes be seen daily. In July and August 2021, as well as August and September 2022, humpback whales were spotted in the sheltered anchorages. Summer is also when typically the most hammerhead sharks are in the area. Visibility can be lower during this time, ranging from 90-ft down to 30-ft with plankton in the upper water column, but rain itself usually only lasts for 2 or 3 hours in the afternoon. Water temps around 80F. And of course, everything shoreside is blooming with life and incredibly green during this season. Hiking the island will be offered. Special kudos to the government of Costa Rica for banning the fishing of hammerhead sharks.

Sample Itinerary

Sample Itinerary

On arrival, a 90 minute shuttle transfer from San Jose airport to a resort close to where your ship will be berthed. We recommend arriving early to enjoy what Costa Rica has to offer!

Day 1: 7:30 pm board at the marina and depart.

Day 2: At sea. Travelling to Cocos Island.

Days 3 – 9: Dive, dive, dive plus go ashore on the “real Jurassic park”!

Day 10: At sea. Travelling back to port.

Day 11: Morning arrival at the marina. Disembark 8:30am for resort stay or shuttle back to San Jose airport.

Frequently Asked Questions

Cocos Island of the Sharks – FAQs


What dive experience is needed?
50 logged dives and advanced open water is the bare minimum experience required to safely dive around Cocos Island. More experience is better and all divers should have good buoyancy skills. The diving can be challenging. There could be strong current on some dives. Some of the dive sites are in open water and exposed to the swell. The difference between Cocos and a destination such as Socorro is that there is no navy base or airstrip on the island which means that airplane medevac is not possible. If you have a medical issue, the boat will have to return to port or at least be met part way by fast boat. For all these reasons, these trips are best suited for good experienced divers. Don’t worry if you don’t feel that you are quite ready yet for Cocos!! Come and visit us in Baja, Sea of Cortez and Socorro and we will get you all tuned and tweaked up for this great adventure!!!

How many dives can I expect?
Your dive schedule may vary according to weather, other dive boats and where the action is. You can generally expect 2 dives in the morning and 1 in the afternoon. Entry into the park is restricted and tightly controlled for diving allowing for not more than 65 divers in the park at any one time. An 11 day, 10 night trip provides for 7 dive days.

What are your safety protocols?
Safety, excellence in guest experience and happy staff and crew are the cornerstones of our business. Nothing is more important than your safety. At Nautilus, we are proud to be the only dive operation in the world with ISM certification and external annual audit of an SMS (Safety Management System). This is the same certification as the largest cruise ships on the oceans. We operate within written processes, procedures and checklists that our captains and crew are trained into both initially and annually. Every dive starts with a briefing on a white board. All divers must be equipped with a Nautilus Lifeline, SMB and dive-alert which are lent out as needed. WE carry AEDs and extensive medical kits with a contract medical officer available shoreside via our sophisticated satellite communication system. NOTE: because of the remoteness of Cocos Island, we highly recommend a medical checkup before leaving on this trip.

Do I need to dive with a divemaster?
Yes. At Cocos, current and visibility can change dramatically within several hours. If you were to surface unexpectedly mid-dive, there is the possibility of drifting away and needing to use your Nautilus LifeLine to get rescued. In addition to those challenges, local tiger sharks can show erratic behaviour around your safety stop at 15 feet and it’s very important for our divemasters to keep a watchful eye on them. For all of these reasons, Cocos is a dive destination in which guests have to stay with our divemasters. Our divemasters are highly experienced and excellent and they will do their best to give you all the freedom and headspace you might be looking for in your diving, and of course, we are very focussed on giving shooters what they need (sorry, bad pun).  Ultimately, your captain and divemasters are the final authority on whether a guest can do a specific dive or not.

Is there nitrox onboard?
Yes. And it’s mandatory for all divers. The cost is US$ 120 per trip.


What airport do I fly into?
Costa Rica Airport or Juan Santamaria international Airport (IATA: SJO, ICA, MROC) which is the most important international airport servicing Costa Rica.

How do I get to the ship?
Standby for more information. We are making arrangements with a resort and marina that is a 90 minute transfer from SJO. Our idea is that you disembark your airline flight with a convenient transfer to the resort with the choice of a number of hotels. Relax. Enjoy several days. And then board the Nautilus Explorer for 3 hour voyage to Cocos.

What time can I board the ship?
Evening board at 7:30 pm with more precise details to follow. Depart shortly afterwards. Next day at sea and then arrive at Cocos the following morning ready to dive!!

What time do we disembark?
Breakfast and then 8:30 am disembark on the last day of your adventure. 90 minute transfer back to SJO or stick around for more vacation time in Costa Rica. An afternoon flight home works out perfectly.

What dive gear do I need to bring?
We provide aluminum 80 cu. ft tanks and weightbelts. Larger steel rental cylinders are available.  5 – 7 mm wetsuit (and hooded vest if you get chilled) are recommended. We have rentals onboard by prior arrangement for almost anything you need. Given the expeditionary nature of these trips, please make any rental requests prior to June 30th and we will bring your rentals down from Baja

What to Expect

Water temperature?
78- 82F. (25 – 28c)

What’s the weather like and what clothes should I bring?
Well, it’s the rainy season in the tropics!! We recommend casual and cool attire onboard (t-shirt and shorts). It can be drizzly in the afternoons and we recommend bringing a windbreaker and a fleece vest or sweater just in case. Make sure you bring good shoes if you are interested in going ashore for a hike. It’s spectacular onshore. Just wait until you see the waterfalls!

What’s the crossing like?
It’s an open ocean crossing.  It can be smooth or it might be rough or more likely, something in-between. The good news is that the Explorer is a heavy and stabilized ocean going ship that has been all over the pacific. We highly recommend the scopolamine “patch” and a glass of red wine to relax and have a snooze on the crossing. During the trip, we anchor in the calm anchorage behind Cocos.

Is there internet and WhatsApp onboard?
Yes. We have a sophisticated KVH VSAT system with internet and what’s app connection available for $120 per trip. Please keep in mind that a satellite tracking system at sea only gives limited speed internet access. You won’t be able to stream Netflix!!

Is there a fuel surcharge??
Of course not! We figure that dive boat companies that with fuel, surcharges year-in, year-out are just taking an extra fee onto the trip.

What fees do I have to pay?
Park fee of US$ 70 plus 13% VAT per day is added to your trip fee during the booking process as is a 5% tax. There are no other fees or surcharges.

Is there anything else I need to pay for onboard?
Bar (which includes fine wine, single malt, craft beer and much more) is not included. Neither is gift shop purchase or crew gratuities.

What’s an appropriate crew tip?
US$ 350.

Ocean and Rainforest Adventures

Ocean & Rainforest Adventures

Join us for an exciting adventure that combines peak season diving with exploring the rainforests of Costa Rica. Could there be a better combination? Reminiscent of the old days when we were exploring and adventuring in Alaska and Haida Gwaii, there will be ample opportunity for diving, kayaking, relaxing on pristine white sand beaches, and hiking into the rainforest that is home to a range of monkeys, lizards, parrots, toucans, hawks, sloths, and iguanas. We will see dolphins for sure and hare hoping for Manatees. Summer is the best diving visibility of the year, and it’s prime time for visiting humpback whales and for nesting turtles. Guided with local expertise, we plan on diving at Bat Island (famous for its bull sharks), Catalina, and Cano Islands.

We have been reading about local crocodiles and are excited to try and find them. Which is exactly the point – these first trips are expeditionary in nature. Captain Mike will be leading the first trip, and while we will research the heck out of the area, we are not sure what we are going to encounter. We’ll have our eyes open, have drinks ready for sunset cocktail hour, and we have discounted these first trips to ensure that no matter what, they are a great value.


Sample Itinerary

Sample Itinerary

Coming soon!

Frequently Asked Questions

Ocean & Rainforest Adventures – FAQs

Coming soon!

Get Inspired!

Get Inspired

Watch our Cocos Island videos