Your adrenaline kicks into the red zone as the shark glides past, dead silent, an arm's length from your face. He's Carcharodon carcharias, the great white, and this isn't an aquarium. It's his realm. You're sharing the water with the world's largest predatory fish, protected (this is the good news) from his infamous dental work by a cocoon of welded aluminum bars, floating at the stern of a luxury live-aboard trawler. Welcome to shark-cage diving, a thrilling, increasingly popular breed of adventure vacation.
The excitement begins underwater, as everyone nervously scans the void around and below the cage, searching for the day's first sighting. Suddenly, some eager diver will pound out a bass drum soundtrack on the bars, to announce the approach of a great white, looming up from its cruising depth. The drama is palpable. A shark rises into Windex-blue water near the surface, and muffled cries of "wow" can be heard beneath the noisy bubbling of everyone's breathing regulators. As the shark slows to inspect these strange creatures in their metal enclosure, a rare communion occurs-an intimate close-up glimpse at one of nature's most mythologized wild animals. But this is no kumbaya moment. Keep your hands inside and respect these efficient killers.
Adult great white sharks typically grow to lengths of around 15 feet-plus, and weigh upwards of a ton. They are the ocean's "apex predators," the ultimate expression of a line of marine vertebrates who've lived on this planet for 400 million years. To scientists and shark buffs, the great whites are a feast of complex behaviors: they're coy in their breeding and migration habits; they're surprisingly wary, calculating hunters; and they're probably the most skillful killing machines in nature.
The inshore waters of Guadalupe Island, located 250 miles off Baja
California, are among the few known stopovers for migratory great whites. Patric Douglas, of Shark Diver, the San Diego-based cage-dive operator, believes Guadalupe is "the most robust white shark habitat on earth." It's now a popular venue where tourists in wetsuits and face masks can safely observe this ancient, dangerous life form in its natural lair.
Strictly speaking, shark-cage diving isn't really diving at all. Usually, no scuba certification or even swimming skills are required. In a typical scenario, "divers" are safety-briefed, then descend just beneath the surface, with unlimited air supplied-hookah style-from topside, via scuba mouthpieces and rugged 12-foot hoses. Most cage dive boats spend about three days at the island, (Shark Diver's price for the total five-day expedition is around $3,100), each diver making four to five one-hour "rotations" daily, with periodic rest breaks on deck.