Facebook
Twitter
We're struggling to make any progress against a fierce and unrelenting current off the southwest coast of Cocos Island. Gripping a barnacle-covered rock, I manage to inch myself forward while gazing in wonder tinged with jealousy at several hammerhead sharks effortlessly holding position in the fast-moving blue water.
Suddenly three majestic manta rays appear, gracefully passing by in a tight flight formation with remoras glued to their undulating wings.
Back on the surface, I savor the memorable encounter as the crew in the chase boat begins plucking our group from the rolling waves. After this dive, we'll definitely have a story to tell Wayne Hasson and his guests back on board the Okeanos Aggressor.
In today's increasingly developed world, the term ''unspoiled paradise'' is probably used far too frequently. But it is indeed an apt description of Cocos Island.
The world's largest uninhabited island, Cocos is situated about 375 miles off Costa Rica's Pacific Coast. Volcanic in origin, the island's forbidding cliffs and peaks are home to a lush tropical rainforest, a crumpled warplane and countless picturesque waterfalls that tumble down to its rocky shoreline.
First used as a hideout by pirates who relished the island's remote location and plentiful freshwater, Cocos later served as a Costa Rican penal colony. Today it is a protected national park revered throughout the scientific world for the endemic species 
that have evolved in this unique natural laboratory
Though the landscape of Cocos was featured in the opening footage of Jurassic Park, it's best known to divers for high voltage underwater action featuring sharks, sharks and more sharks.
Presented with the unexpected opportunity to join Wayne Hasson, the founder of the highly successful Aggressor fleet of live-aboards, on a special expedition to Cocos, I jumped at the chance to make my first dive foray in the Pacific.
The recent trip was intended to commemorate Wayne Hasson's first visit to Cocos back in 1989. He had heard stories about the island's abundant sharks and marine life, but naysayers scoffed they were certain that few divers would be willing to brave the 34-hour boat ride to the island from Puntarenas, a sleepy Costa Rican fishing village. So Wayne invited a group of dive industry professionals to come see Cocos for themselves on the 110-foot Okeanos Aggressor.
What they discovered was a vibrant and thriving marine ecosystem with dense concentrations of pelagics in other words, a diver's dream destination. Since then, at least two other live-aboards have joined the Okeanos Aggressor in making regular trips to Cocos Island.
For the recent visit, Wayne Hasson put together another eclectic group that included TV celebrity David Hasselhoff, famed marine artist Wyland, representatives of three diving magazines, officials from PADI and DEMA and some of Aggressor's most highly regarded wholesale and retail travel partners.
While the crossing to Cocos does take awhile, the time passed pleasantly enough as the spacious yacht sliced through relatively calm seas. Pods of spinner dolphins appeared on both sides of the boat on the first morning crewmembers say they also occasionally see blue whales during the voyage. Some passengers killed time reading on the sundeck, others watched videos in the salon while still others fiddled with dive gear or napped in their air-conditioned cabins.
After dinner, I spent an hour on the bow staring up at the Milky Way, which resembled a low flying cloud in the impossibly clear sky.
The boat arrived at Cocos at 2 a.m. but the cloud-shrouded island's stunning beauty wasn't fully revealed until the sun illuminated it a few hours later. By 8 a.m., we were backrolling into the ripping currents off Isla Manuelita for our first dive.
During the course of 10 dives in the next three days, I saw hundreds of whitetip sharks, dozens of hammerheads and marble rays, as well as numerous silvertip and silky sharks. The six sightings of manta rays were unforgettable, as were the massive schools of jacks and grunts.
Though there is little coral growth in Cocos, the sloping underwater walls and ledges are alive with lobsters, morays and sea urchins. A pair of motionless yellow frogfish and several octopus stole the show during a night dive.
Water temperatures averaged a comfortable 80 degrees, though signficantly cooler water is found in thermoclines. Most of the dives take place in challenging currents this is not an ideal environment for inexperienced divers. If you go, a pair of dive gloves will come in handy.
Throughout the past decade, the Aggressor Fleet has worked with park officials in Costa Rica to make sure that the ban on fishing at Cocos Island is strictly enforced. Thanks largely to these efforts, Wayne says the diving there is still as good today as it was on his first visit.
After completing the last dive on a site called Submerged Rock, our boat driver throttled back as we crossed a bay where a manta ray had been sighted the day before. Minutes later, we saw the fins of two mantas break the surface. Grabbing snorkels and fins, divers clamored into the water for an encounter with these underwater flying machines.
Fifteen minutes later, everyone was back on the boat and we were set to depart when the larger of the two mantas approached for a final pass. It came to within three feet of the port railing before executing a slow summersault that elicited a roar of cheers from the grateful spectators.
It was one of those Cocos moments that make a long boat trip worthwhile.
