"You're more likely to be attacked by lightning or by your own toilet than you are by a shark."
--Peter Benchley, author of the novel Jaws and cowriter of the film's screenplay

One of 60 unforgettable seconds with a whale shark (and its hitchhiking sucker fish) in the Galápagos Islands.

A MILE OFF DARWIN ISLAND IN THE GALÁPAGOS, we are drifting 30 feet underwater in the bottomless blue. We've left the rocky reef surrounding Darwin's Arch, with its colorful fish and hundreds of hammerhead sharks, and it feels empty. We may see nothing at all. But we get lucky. Suddenly our dive guide sprints off into the current. We follow and, within seconds, spot a dark hulk the size of a bus gliding through the plankton. My wife, Rosie, swims within feet of the leviathan, and I snap photos as fast as I can.

It's a whale shark--the largest fish on Earth, growing up to 45 feet long and weighing up to 40 tons. We feel a surge of adrenaline, but not because we are afraid. The whale shark is a filter feeder, living off plankton and other tiny morsels, and is harmless to humans. Though most other sharks are predators, humans are not their natural prey. Of some 400 shark species, only 4 pose a serious risk: great white, tiger, oceanic whitetip, and bull. The others generally avoid people unless threatened, though some will approach divers out of curiosity.

Sharks themselves are threatened by the world's most prodigious predators: humans. Commercial fishing operations kill about 100 million annually. Shark meat is all too popular, as is shark-fin soup, for which these beautiful animals are "finned" and thrown back into the water to die. Humans have left some 200 shark species at risk and 20, including the whale shark, in danger of extinction.

Awestruck by this immense wild creature, I swim along its dappled body. As I near the head, its eye moves. The gentle giant is watching me. Soon Rosie and I begin to tire. The shark is in no hurry, but we can't keep up for long. The entire encounter has lasted maybe 60 seconds--an eternity when your heart is pounding. The ten-foot-high tail fin passes, and the shark disappears into the void. --Robert Heil

ON THE WEB For information on shark protection, go to the Monterey Bay Aquarium's "Seafood Watch" at mbayaq.org and to wildaid.org.

photo by Robert Heil, used with permission