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Dive Review of Okeanos Aggressor in
Costa Rica/Cocos Island

Okeanos Aggressor: "my first liveaboard and it was fabulous", Jun, 2019,

by Gene S, TN, US ( 2 reports with 6 Helpful votes). Report 11355 has 2 Helpful votes.

No photos available at this time

Ratings and Overall Comments 1 (worst) - 5 (best):

Accommodations 4 stars Food 4 stars
Service and Attitude 5 stars Environmental Sensitivity 5 stars
Dive Operation 5 stars Shore Diving N/A
Snorkeling N/A
Value for $$ 4 stars
Beginners 1 stars
Advanced 4 stars
Comments First a disclaimer. This was my first liveaboard, so I have no reference point for my evaluation. My ratings are based simply on the experience, which was quite good overall. We got lucky on this trip as the weather was about as good as it gets. The crossing to and from Cocos Island was very smooth and it took only 30 hours to get there (normally 35) and less than 30 to return. Weather during the week was generally good and although we had some cloudy and rainy days, the surface conditions were good on all days.

Given that this was my first liveaboard I was a little apprehensive about the long crossing. But the calm seas caused it to be an excellent part of the overall experience. It's a good time to get to know your fellow divers, prepare your gear and just get relaxed and mentally prepared for the rigorous diving. On the return, it's a good opportunity to dry your gear rather than hurriedly getting off the liveaboard after having just dove a few hours before, as is the case with most liveaboards.

Food was very good and you could not go hungry. My favorite meal was sushi night on the upper deck, including an alternative for those who don't like sushi. All of the crew was extremely friendly and hard-working. They had specific roles but it was not uncommon to see them helping each other regardless of their duties. Cabins were adequate but I was mostly there for sleep. There is a designated smoking area and fortunately we only had 1 smoker in our group, although it seemed that half the crew smoked but they were more discreet about it.

On the main boat, the dive deck is laid out very nicely with your own personal storage station, overhead showers, 2 nice-sized dunk tanks (for cameras), a large camera table with 2 low pressure air hoses for drying your camera quickly. There are ample charging stations.

The diving is really quite different than most of the tropical type diving I've done. 5 mm wetsuit with beanie (didn't even have a full hood) was more than adequate. Water temperatures were surprisingly warm, mostly 80-82 F (27-28 C) but it was not unusual to encounter thermoclines that dipped to 73 F (23 C). One diver wore only a shorty for the entire week but with 3-4 dives per day, I wouldn't recommend. Hardy gloves are important because you are often hanging onto rocks in a current. Nitrox is an extra charge but a must-have, given the depths and number of dives per day. We did 22 dives in 7 days.

Diving is done from 2 zodiak-style pangas. Max 11 divers + DM + boat captain per panga. While space is somewhat tight, their processes of getting divers on and off the main boat and in and out of the water is very efficient. I felt a little clumsy on the first dive but after that it was relatively easy. I was impressed with the quality and experience of the other divers and this helped a lot. The DMs alternated pangas each done, so that we had Captain Mauricio one day and Warren the next day and so on. This was nice because you get two slightly different approaches to the dive profile. Mauricio carries a camera and shares his pictures at the end of the trip. Warren shot video and puts together a video for purchase, which was well worth the modest cost.

Diving is all about the sharks. Mostly divers come for the Hammerheads but there are Whitetips present on every many Whitetips that I found myself ignoring them. We saw Hammerheads on most dives, sometimes 50+ during our safety stops which were always done in the deep blue. They are rather shy so getting close was always a challenge. But overall it was spectacular viewing during the entire week. There are also Tiger Sharks in the area, including one that killed a diver and injured a DM in late 2018. We were thoroughly coached about this shark during the main briefing on the ride over but we never encountered it. One diver got pics of a couple of Tigers but that was the only sighting. A couple Galapagos Sharks.

There are Marble Rays in abundance as well, seeing them on most dives. We encountered huge schools of Jacks (easily 1000+) away from the land structures and in the blue. Also an occassional Wahoo pair in the blue. Other notable sitings include Guineafowl Puffers (including the rare yellow-colored), Trumpetfish (including yellow-colored), Porcupinefish, male Spotted Boxfish, Bluefin Trevallies, Peacock Flounders, Ocean Triggerfish, Lobster, Yellow-spotted Eels, big schools of Bluestripe Snappers and Urchins everywhere you looked. A few Eagle Rays that were not shy and we were able to get close without scaring them off. Only 1 turtle. Someone found a Mantis Shrimp but I missed it. And massive amounts of small schooling fish everywhere.

Favorite sites were Manuelita (3 different sites) and Dirty Rock, where we definitely had the most Hammerhead encounters. Of the 22 dives, 8 were at Manuelita and 7 at Dirty Rock. It never got boring.

We had 2 opportunities for shore visits in 2 different locations, once each in Chatham Bay and Wafer Bay where the 2 ranger stations are located. I highly recommend both. You will get a much greater appreciation for this unique place when you visit the land in addition to the underwater. You will also better understand the commitment of the Rangers to protecting this wonderful place.
Websites Okeanos Aggressor   

Reporter and Travel

Dive Experience 251-500 dives
Where else diving Caribbean, Maldives, Fiji, Fr. Polynesia, Australia
Closest Airport San Jose - SJO Getting There Direct flights from all the Caribbean gateways - Miami, Atlanta, Houston, Dallas.

Dive Conditions

Weather sunny, rainy, cloudy Seas calm, choppy, surge, currents
Water Temp 77-82°F / 25-28°C Wetsuit Thickness 5
Water Visibility 50-80 Ft/ 15-24 M

Dive Policy

Dive own profile no
Enforced diving restrictions Must have own dive computers. SMB required. No deco diving. GPS tracker is provided and required. No solo diving.
Liveaboard? yes Nitrox Available? yes

What I Saw

Sharks Lots Mantas None
Dolphins None Whale Sharks None
Turtles 1 or 2 Whales None
Corals 2 stars Tropical Fish 5 stars
Small Critters 4 stars Large Fish 5 stars
Large Pelagics 5 stars

Underwater Photography 1 (worst) - 5 (best):

Subject Matter 4 stars Boat Facilities 4 stars
Overall rating for UWP's 4 stars Shore Facilities N/A
UW Photo Comments Nice large camera table on the main diving deck. Rubber mat and 4 inch sidewalls to prevent things from rolling off. 2 low pressure air hoses to "blow dry" the camera housings. 2 large dunk tanks with fresh water for cameras only.
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Note: The information here was reported by the author above, but has NOT been reviewed nor edited by Undercurrent prior to posting on our website. Please report any major problems by writing to us and referencing the report number above.

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