Cocos Island Dive Sites
Hammerhead sharks circle the volcanic seamount of Cocos Island by the hundreds. Beside them, divers may cross the path of lumbering whale sharks, gliding eagle and manta rays, slithering moray eels and a wide array of different shark species swarming schools of tuna, snapper and hundreds of other tropical fish species. Recognized as one of the world's top ten scuba diving destinations, Cocos Island offers divers a surreal underwater experience. Brimming with vast seascapes and copious amounts of marine life, Cocos is nothing short of a diver's dream. The island is a national park found 340 miles off Costa Rica's south Pacific coast; a 36-hour boat ride from mainland.
read more closeCocos Island is one of the few dive sites on the planet where it is possible to observe a remarkable variety of species inhabiting a single place. At least 32 types of corals, 57 crustaceans, 118 mollusks and 250 fish species occupy these nutrient-rich waters and rocky pinnacles. Due to its isolation, Cocos has very few tourists other than experienced divers who book 10-day scuba safaris with private tour companies. Divers live on cruise ships during their journey to the island; diving three or four times each day. Night dives provide opportunities to view hundreds of whitetip reef sharks hunting and fighting one another for a prey. The best time to see large groups of hammerhead sharks is during the wet season, from May through late November. Visibility is better and currents tamer during the dry season (Jan-April). It is best to avoid diving during El Nino events, which decrease fish populations every three to four years.
General Information
Aquatic life: The island’s volcanic seamounts serve as an enormous shark cleaning station, attracting unprecedented numbers of hammerhead sharks. Other species include: whitetip reef shark, blacktip shark, Galapagos shark, bull shark, whale shark, silky shark, dolphin, spotted eagle ray, manta ray, marble ray, octopus, bigeye jack, green sea turtle, moray eel, tuna, snapper, soldierfish, Commerson's frogfish, rosy-lipped batfish, barberfish, moorish idol, marlin and sailfish. Though there's a cornucopia of coral species, there is not a large quantity at Cocos Island, so divers will not see as many colorful reef fish.
Average visibility: 20 to 80 feet
Best time of year: The best visibility is during the dry season (Dec.-March), when silky sharks and rays are plentiful. Hammerheads are present, but in small numbers. Most divers would agree that the best time to go to Cocos Island is during the wet season (May-Dec). While conditions are not as ideal in terms of visibility and currents, these months afford the best chances for viewing legions of hammerheads. Avoid diving during El Nino events, when warm waters cause decreased populations of fish.
Skill level: Advanced divers only
Surge/current: Strong currents.
Thermoclines: Thermoclines (steep temperature gradients that can be felt descending through layers of water) are present.
Water temperature: 78-82 degrees November to May and 76-80 degrees June to December.
Wetsuit recommendation: Wetsuits are always recommended to protect against stings and scrapes from sharp rocks, sea porcupines, scorpionfish and other nuisances.
Dive sites
Manuelita Inside: Manuelita is a great place to observe marbled rays, moray eels, and lobsters. Depth: 20-70 feet; visibility: 65 feet.
Manuelita Outside: Large rocks and boulders hide places for divers to watch hammerhead shark cleaning stations – areas where cleaner fish pick parasites off hammerhead bodies. Depth: 60- 130 feet; visibility: 65 feet.
Manuelita Coral Gardens: An easy, shallow dive that is usually used as an introductory dive site for live aboard expeditions. It features lots of colorful snapper, parrotfish and whitetip reef sharks. Depth: 90 feet; visibility: 65 feet.
Manuelita Channel: The strip between the main body of Cocos Island and smaller Manuelita Island. Currents can be strong here, and tiger sharks are known to pass through the channel. Depth: 90 feet; visibility: 65 feet.
Isla Pajara: Just off of Weston Bay, this site is a habitat for Commerson’s frogfish, moray eels, Cocos batfish and green sea turtles.
Viking Rock: Staircase like surfaces along this submerged reef create a variety of habitats and hiding places for sea life like eels, lobsters, and octopi. Viking Rock is also a great place to see whitetip reef sharks and marbled rays. Depth: 50-130 feet; visibility: 65 feet.
Dirty Rock: Dirty Rock is one of the most dynamic and popular dive sites in the area, and also one of the best places to see scores of hammerheads. Schools of barberfish as well as bigeye jacks are also common. Depth: 20-130 feet; visibility: 65-80 feet.
Punta Maria (Maria Point): This sea mountain features two pinnacles and strong currents. It can only be visited when waters are not too rough. Depth: 80-120 feet; visibility: 65 feet.
Dos Amigos Grandes (Big Two Friends): Divers can pass beneath a picturesque arch that towers from up above, and then view a busy shark cleaning station. Depth: 60-130 feet; visibility: 65-80 feet.
Dos Amigos Pequenos (Small Two Friends): This southernmost part of the island can often not be accessed during the wet season due to strong currents, but when it can be visited, it is hammerhead heaven. Depth: 60-120 feet; visibility: 65 feet.
Bajo Dos Amigos (Lower Two Friends): Only explored during the dry season (Dec.-March), Bajo Dos Amigos is the best place to see rare black coral. This is a deep dive for advanced divers. Depth: 90-130 feet.
Shark Fin Rock: A steep incline forms a natural staircase of sorts, providing ample hiding places for moray eels and octopi. Depth: 40-130 feet.
Bait Ball: Beautiful bait balls – clusters of baitfish that clump tightly together to confuse nearby predators – commonly occur here. Depth: 0-20 feet.
Submerged Rock: This incredible dive site is a sure bet to see pregnant whitetip reef sharks and their young. Light shines through a large hole in the seamount where divers can shimmy through to the other side, passing by scores of snapper, creole, soldierfish and parrotfish. Depth: 20-110 feet.
Bajo Alcyone: Known commonly as just “Alcyone,” this site is known for its hundreds of hammerheads, enormous manta rays and general explosions of marine life. Discovered by one of Jacques Cousteau’s exploration teams, Alcyone is one of the deepest cleaning stations at Cocos Island. Depth: 90-120 feet; visibility: 65 feet.
Silverado: This dive site is the only known cleaning station in the area for silvertip sharks. You’ll either see extreme numbers of silvertips or nothing at all. Depth: 30-40 feet; visibility: 65 feet.
Lobster Rock: Endemic to Cocos Island, the unusual looking rosy-lipped batfish can be found at depths of 90 to 120 feet. Commerson’s frogfish, whitetip reef sharks and marble rays are also prevalent here. Depth: 40-110 feet; visibility: 50 feet.