Rachel Graham may be the shark's fiercest protector – an Oxford-educated biologist who isn't afraid to wrestle a bull shark into submission.
Credit: Photograph by Peter Bohler

The boat is pitching and reeling when the Shark Lady picks up her power drill. A Shaq-size monster is banging the shit out of the side of our vessel. There are eight onboard, but six of us are rookies – we know not what to do. Only the Shark Lady is certain. She barks orders at the men.

"Get a rope around him. Now roll him over. Now grab his ding-dong! No, grab his other ding-dong. Yeah, that's right. Watch how docile he gets. Just like a man. He's entering tonic immobility."

The guys do as they're told, and the shark is brought parallel to the boat. Rachel Graham reaches into the water and grabs the first dorsal fin of a seven-foot-long, 300-pound Caribbean reef shark. She flips on the drill. A high-pitched whine cuts through the duller sound of whitecaps slapping our boat a couple miles off the coast of Belize. The drill burrows into keratin, sending up a fine mist of eau de shark. Our aquatic friend is not amused. He regurgitates his stomach. This won't do. The Shark Lady pushes the white lining back into the shark's mouth like a magician disappearing a hankie.

That's when the shark makes pleading, beady eye contact with me. Sharky, don't look at me like that! I am not Ishmael; I am Stephen, secret puker and scarfer of Dramamine. I cannot help you. Besides, this is for your own good. Just ask the Shark Lady.

Maybe i shouldn't call Rachel Graham the Shark Lady. Sounds reductive and sexist, even if she is the one who taught me that male sharks have two penises. Mom raised me better. The Shark Lady is a serious person: She went to Oxford, rowed crew, and has a Ph.D. in marine biology. She's got two boys, once swam through a giant cloud of whale-shark shit, and has no problem taking a piss off the side of the boat in front of her all-male crew. And Graham isn't drilling sharks for some weird fetish – she is giving them satellite tags so she can see where they go, what they eat, and, most important, what she can do to keep them alive.

OK, she is definitely the Shark Lady. But Graham doesn't really mind what you call her. What I'm worried about is that she will be pissed about me describing a harmless Caribbean reef shark as a monster. That's what got the poor sharks into their current conundrum, tarted up as mass murderers on TV, hunted for sport by fat guys on Caribbean benders, and harvested for their fins so some rich Chinese guy can serve shark-fin soup at his daughter's blowout Beijing wedding.

Some eco groups suggest that as many as 73 million sharks are killed globally every year. Hammerheads, blue sharks, mako sharks – they're disappearing, and they ain't coming back.

Unless activists like Graham have a say. Most of Graham's life is now spent trying to reverse the damage that has already been done. She tells me that because sharks are almost all cartilage, there are no skeletons to recover and study. Basic information about their lives still eludes scientists.

"We don't even know how long they gestate – no idea," explains Graham. "We can't save them if we don't know where they go and how they live."

Graham is trying to solve the mystery by tagging sharks and following their travels. Some of the information falls into the arcane: She has learned that pregnant female reef sharks spend more time closer to the reefs feeding than do males. Other data is more depressing: Baseline surveys she's taken since 2006 indicate that Belize has few sharks overall, compared with relatively underfished sites in more remote parts of the Pacific. The primary cause is overfishing, first by Belizean fishers and then by fishers from neighboring countries. Similar problems are depleting sharks across the globe.

One night, we're having dinner at a restaurant on Caye Caulker, a spit of a Belizean island not far from where we cruised for sharks earlier in the day. Before we sit down, Graham points out that the chef is grilling endangered bonefish. Graham is close to six feet tall, 46 years old, with massive guns and kind blue eyes that turn ice-cold if she's angry (a rare thing). For a minute, I think she's going to throw down with the chef, but she just sadly shakes her head. "They're cutting their own throats," Graham says matter-of-factly. "The thing is, that kind of fish has a lot of bones. Their customer is not even going to want to eat it."

After a drink to take the edge off, mostly mine, I ask her if she minds me using the term monster to describe sharks. She waves me off with a smile.

"Go ahead. Monsters make us feel alive. Monsters make us feel like we're part of some bigger whole."

She pops a piece of grilled pineapple into her mouth and finishes her cocktail. We walk out past the outlaw chef, and she flashes him an "I've got my eye on you" look. She buys an ice cream cone and returns to my original question.

"There's a reason why we have to make sure we don't kill all the monsters. We need our monsters."