The 'Wall of Sharks' Is an Actual Phenomenon, and It Only Happens Once a Year

The 'Wall of Sharks' Is an Actual Phenomenon, and It Only Happens Once a Year

If you’re a fan of Jaws, The Meg, or the totally realistic Sharknado, you might hear the phrase “Wall of Sharks” and think you’re in for a brand-new ocean-centric thriller.

And you’d be right—but the thrills here aren’t seen on the big screen. Instead, the Wall of Sharks is a totally real phenomenon that you can actually experience in person (if you’re in the right place at the right time, that is).

The nickname is used to describe an annual gathering of hundreds of sharks off the island of Fakarava in French Polynesia. As one of the largest shark sanctuaries in the world, the waters surrounding the island are typically teeming with the sea’s apex predators. A narrow pass, where the open sea meets a lagoon, is particularly rich with sealife, from plankton to fish, that attract hungry sharks at any given time.

© Grégory Lecoeur | Grégory Lecoeur
© Grégory Lecoeur | Grégory Lecoeur

But once a year—on the full moon in July—the south passage goes from casual dining to full-on buffet. That’s because it’s at this precise moment, while the sharks arrive to feast, a slew of marbled grouper are also arriving to mate. Biologists first discovered the surprisingly high numbers of gray reef sharks while studying the aggregation of groupers, which travel from near and far to spawn in numbers that surpass 20,000 (it’s thought to be the largest known aggregation of large reef fish).

Related: Scientists Have Discovered the Real Reason Why Whales Jump:

But the researchers soon found that groupers weren’t the only gilled creatures hanging around. The pass, where 250 sharks typically linger in the warm summer months, suddenly saw an influx of up to 900 sharks at once. And in a relatively small patch of water—at just over 300 feet wide, the pass is narrow enough that “when diving inside, you can see both sides of the channel,” says shark researcher Dr. Johann Mourier—that’s a significantly high concentration of sharks.

Grégory Lecoeur
Grégory Lecoeur

Hence, the apt nickname Wall of Sharks. Since word spread about the fascinating phenomenon, the site has become a popular spot for brave divers from around the world. Top Dive, a company that hosts guided dives around French Polynesia, offers trips to the pass year-round, including during the fleeting Wall of Sharks timeframe. (Even if you miss the July full moon, however, the south pass of Fakarava is a “veritable undersea Garden of Eden” year-round, according to Top Dive.)

And if you’re thinking what we’re all thinking, let your worries be appeased: Underwater photographer Laurent Ballesta says the sharks see humans merely as “obstacles not prey” so divers are generally safe. And, contrary to what Hollywood might have you believe, sharks really aren’t the mindless killers we make them out to be, but rather a vital part of the ecosystem in need of protection.

So, whether you’re ready to slip into a wetsuit or not, can we all just agree that this is pretty much the coolest thing ever?