10 Things You Might Not Know About Hunting Pirate Ships

"How much do you know about the Golden Age of Piracy?" an explorer asked author Robert Kurson over drinks at Scotty's Steakhouse in Springfield, N.J. The explorer, John Chatterton, and his colleague John Mattera had just made the find of a lifetime: They had recovered a pirate ship—the "single hardest and rarest thing a person could discover underwater." The adventure took a full year, culminating in the recovery of the Golden Fleece, described as the greatest pirate ship that ever sailed, in waters off the Dominican Republic. Pirate Hunters tells the story first told to Kurson that night, which unfolds with the joy and excitement otherwise found in an Indiana Jones movie. As revealed in the book, here are 10 things you might not know about pirate hunting and maritime archaeology.

1. DISCOVERING A PIRATE SHIP DOESN'T HAPPEN OFTEN.

When Chatterton and Mattera began their adventure, only one other pirate ship had ever been recovered and positively identified: the Whydah, commanded in 1717 by Captain "Black Sam" Bellamy. (Its wreckage was found in 1984.) Old sailing ships are discovered on occasion, though great wrecks are extremely rare, and positive identification is nearly impossible.

2. HUNTING ANCIENT SHIPS REQUIRES MODERN TECHNOLOGY.

Chatterton and Mattera are among the world's foremost authorities in such technologies as side-scan sonar, which scans the seafloor using soundwaves, and magnetometers, which detect objects by noting changes in the Earth's magnetosphere. Chatterton and Mattera used a magnetometer to find the Golden Fleece. The process involved "mowing the lawn," sailing up and down likely sites. Each ping required the pirate hunters to suit up and dive to the bottom of the sea to investigate.

3. TREASURE HUNTING IS AN ENDANGERED BUSINESS. 

A treaty written by the United Nations Educational, Scientific and Cultural Organization (UNESCO) mandates that any shipwreck over 100 years old belongs to its nation of origin. As countries adopt the treaty, wreck divers are losing fertile hunting ground. While this might be good from an archeological standpoint ("This belongs in a museum!"), it is often the promise of loot that brings divers to spend decades in search of ancient ships, risking life and limb along the way.

4. WRECK DIVING IS A YOUNG PERSON'S GAME.

Deepwater-wreck diving, according to Kurson, is "a sport that pushed the body to its limits and could paralyze or kill a person for the slightest mistake." An expedition might involve full days underwater for months at a time. Shipwrecks often lay at depths "never intended for humans, where water pressure could collapse vital organs, and the buildup of nitrogen could disorient the mind and turn blood to foam." Forty-year-olds are considered old for the field. (During the hunt for the Golden Fleece, Chatterton was 57 and Mattera was 46.)

5. FINDING A PIRATE SHIP REQUIRES SPENDING AS MUCH TIME IN A LIBRARY AS IN THE WATER.

The historical record gave Chatterton and Mattera their first clues: The ship sunk in 24 feet of water; there were muskets on her deck at the time; and when fatally struck by the Royal Navy, the ship had been careening (that is: turned on its side for repairs—a common practice). Careening meant it must be near a beach. History and logic would continue unlocking clues from there. Joseph Bannister, captain of the Golden Fleece, was a genius at sea, which eliminated several possible sites with too much visibility from the Atlantic. His intellect also would have eliminated areas with too much coral.

6. HISTORY IS A DIVER'S GUIDE.

Wreck diving is like playing Sherlock Holmes underwater. In one instance, Chatterton and Mattera detected something, and Chatterton dove to find out what it was. He discovered an anchor—great news!—but it was a "working" anchor—terrible news. A working anchor would have been lowered to the seafloor, business as usual. But they were searching for an anchor that had gone down with the ship. Such an anchor would have been laying on its side.

7. PIRATE HUNTING IS AN ADVENTURE IN ITS OWN RIGHT. 

To get to one site, Chatterton, Mattera, and their team had to travel by truck on a "makeshift road that took them past abandoned towns, feral dogs, and cliffs so muddy a small tire slide would have plunged them into an unfindable grave." The men had to arm themselves when they came to a machete-wielding gang who attempted to block their way. A wild bull lowered its horns to charge, and hungry mosquitoes were everywhere. At one point, Chatterton and Mattera got into an armed standoff with a local carrying a Beretta.

8. PIRATE HUNTERS HUNT PIRATE HUNTERS.

Archaeologists chasing archaeologists isn't just a plot device in Indiana Jones films. Professional treasure hunters keep an eye on one another. When the competition seems on the verge of a find, competitors take to the seas and begin calling in favors with local governments. The goal is to score salvaging rights, or at least, a piece of the action. ("Let's f***ing ram their boat," Chatterton ordered once after noticing a competitor moving in on his site. Pirate hunting is serious business.)

9. MARITIME ARCHAEOLOGY IS EXPENSIVE.

In order to pay the bills, Chatterton and Mattera at one point had to take tourists on scuba dives. Their expedition burned through thousands of dollars a week to maintain equipment, feed the crew, and fuel the vessels. Cell phone service and Internet access ran $700 per month. A specialized cable for the magnetometer cost $4000, and ended up having to be replaced three times. Treasure hunting by definition doesn't pay unless treasure is found. Months into their expedition, Chatterton and Mattera had spent a million dollars and had nothing to show for it.

10. PIRATE HUNTERS AREN'T CHASING THE SHIP—THEY'RE CHASING THE MAN.

All of the known clues to the location of the Golden Fleece suggested an island called Cayo Levantado, but the more Chatterton learned about Captain Joseph Bannister, the more certain he was that he and his team were searching in the wrong place. "Everyone's been looking for a pirate ship," he told his team. "But this isn't about finding a ship. It's about finding a man." Bannister wasn't just any pirate. Before beginning his life as an outlaw, Bannister was a respected merchant ship captain. "In just a few years, the captain had stolen his own ship, outmaneuvered two governors of Jamaica, evaded an international manhunt, and then, despite being outmanned and outgunned, defeated the Royal Navy in battle." Such accomplishments were evidence of greatness, requiring planning, preparation, cunning, and the absolute loyalty of his crew. To find Bannister's sunken ship, they would have to find a place "that reflected Bannister's genius, a place equal to the man." In the end, they did, and Pirate Hunters recounts the adventure.