The islands of Tahiti have some of the world's most beautiful lagoons. These shallow and protected bodies of water form natural aquariums where colorful tropical fish and rays swim in crystal-clear water. And there are sharks.
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But a shark encounter in a Tahitian lagoon isn't an adrenaline-rush experience, because the species you are most likely to encounter is on the shy side and poses little danger to humans. Meet the blacktip reef shark — not to be confused with his larger cousin the oceanic blacktip shark. These guys are on the small side, usually coming in around four to five feet in length. Apart from their size, the obvious giveaway that identifies these sharks is the distinctive black patch on the upper part of their dorsal fin.
While other species of sharks make occasional visits to lagoons, blacktips swim in the shallows most all the time. Their preference for protected nearshore waters and shallow coral reefs is a way to avoid the bigger sharks that might consider them lunch. And it's also where they become the hunter instead of the hunted.
Blacktip reef sharks nosh on fish, octopus, shrimp, and small invertebrates, and they usually hunt at night. They have a keen sense of smell and the ability to locate fish by the weak electrical fields that all living creatures put out. After dark, a blacktip will nose around the reefs to locate a meal that's hiding in crevice or under a ledge.
By day, blacktips usually stay inshore of the coral reefs and idle about in the lagoon. But while they usually swim at a leisurely pace, a quick flick of the tail can propel them to speeds of 25 miles an hour in an instant or launch them several feet into the air, as more than one low-flying bird has unfortunately discovered.
In the wild, blacktip reef sharks are skittish around swimmers and snorkelers, and will usually flee the area when the splashing begins. But in the lagoons of islands such as Bora Bora and Moorea, their fears have been eliminated by years of human interaction — plus the occasional fish bit tossed into the waters by tour guides to attract rays and other lagoon dwellers.
In the absence of food offerings, blacktips take a causal approach to human presence. When a snorkeler enters the water they are often given a once-over by one or more of the blacktips in the area, after which the fish go back to whatever they were doing.
Despite the blacktip's typically nonchalant and nonaggressive behavior, most people still get a bit of a thrill from their first encounter with these sharks. These sharks may swim quite close to the surface with their dorsal fin above the water's surface in classic “Jaws” fashion. The sight of a half-dozen dorsal fins cutting wakes as they approach the boat can create an apprehensive first impression. But once in the water, most snorkelers soon relax and enjoy the encounter.
While blacktips may be the star of the show, stingrays also put on a good performance as they glide across the sand and circle snorkelers. Less frequent but noteworthy appearances are made by lemon sharks. This larger species, which can grow to more than 10 feet in length, is more likely to appear when feedings take place.
These shallow water lagoon encounters are just one of the extraordinary marine life encounters that await in the waters of Tahiti. From swimming with whales in blue water to exciting drift diving in the atolls, these are experiences you'll never forget. Get started on your own adventures by contacting your Caradonna agent.