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
Our days begin at dawn and end after dark. In between, we bob and wobble through whitecaps, sucking on Jolly Ranchers and pissing behind the twin outboard motors. We tag two six-foot-long nurse sharks the first day, but there's a lot of dead time onboard, which makes me appreciate the man-hours put in to get 60 minutes of footage for Shark Week. Graham tells some war stories.

"You can still a rambunctious adult male nurse shark to size and tag it by grabbing its clasper hard," says Graham with a laugh, using the proper name for a shark's two ding-dongs. "The only downside is that it may ejaculate on you, and the sperm is pretty darn sticky. I like to use this technique as a rite of passage for a new colleague, many of whom are dudes and are rather uncomfortable with it."

Things pick up on day three. Hilmar and the boys pull in lines when a buoy bobs, suggesting a big one. The line is pulled up, and there's a large Caribbean reef shark.

Tagging a shark isn't that different from hog-tying a calf at the rodeo: The line is pulled in, a rope is slipped around the shark's tail, and the shark is pulled up beside the boat for tagging. At least that's how it goes in theory. Graham lets Chip and the Belizeans handle this one.

"OK, Chip, walk it back, just like a dog. Hilmar, slip the rope around the tail."

This begins according to plan, but things quickly go sideways. One thing you're not supposed to do to a shark is grab the top of its tail. This is exactly what Hilmar does. Smack! The shark's tail levels Chip.

"Goddamn it, that hurt like hell."

Chip takes a standing eight-count while Graham gently dresses down Hilmar.

"Never grab it by the top of the tail. They freak out. Always by the dorsal fin."

Chip tries again, bringing the shark close enough for measuring, and gets the drill out. But he can't find the right spot, hunting and pecking like a drunken teenager trying to pierce her BFF's ears.

"Fuck."

Graham taps him gently on the shoulder.

"Chip, harmony and good thoughts. That'll calm you and the shark."

The tag's implanted, and Graham cuts the hook from the shark's mouth; it swims off.

Not everyone in the save-the-shark movement is as comfortable with hooking and tagging sharks as Graham. She put one photo of crew members holding a juvenile shark on her Facebook page, and it was greeted with comments like "Plz tell me u put that baby shark back???" This drives Graham a little crazy. "Look, I love sharks, but I'm not a shark hugger – you have to catch them to get the data. It's the long game."

Graham brags that she's had very few sharks die on her in her seven years of hooking and tagging. If that's true, I was the ultimate bad luck. In a one-hour period, Graham hooked two small sharks that swallowed their hooks. While she skillfully cut out as much of the metal as she could, both of them left her hands and started a slow death spiral down to the bottom of the ocean. She slammed her pliers back into the tackle box.

"I'm going to have nightmares about that."

But that isn't the bleakest endgame.

Belize has established no-take marine reserves around its islands, but Graham's research shows that the so-called reserves around Belize have no more sharks than do unprotected waters. This is likely due to a couple of factors: Sharks are highly mobile and readily move beyond boundaries, and, more depressing, there's been a lack of effective enforcement in the protected zones. During my six-day trip, we ran into exactly two Belizean police boats, manned by personnel whose sleepy torpor suggested Paul Blart with an outboard motor.

"We need to know more," Graham tells me over breakfast one morning, as a nearby tour boat takes divers out in search of manta rays, coral reef, and mostly vanishing sharks. "If we want to save them, we have to know more. And do much more."