The vessel believed to have been Blackbeard’s flagship is currently occupied by octopuses, which turn a pale, disgruntled green when nautical archaeologists approach. Black sea bass nip at the excavators’ ears, and moray eels spill out of the mouths of cannons, many of which are still loaded.

But after nearly 300 years in the North Carolina shallows, the remains of what may be the Queen Anne’s Revenge are surfacing, plank by worm-eaten plank. The site, discovered in 1996, is 25 feet underwater, less than a mile and a half from shore. But long weather delays during diving seasons and uncertain funding have slowed the excavation—this past fall’s expedition was the first since 2008—and it can take years to clean and analyze artifacts corroded beyond recognition. Still, with objects recovered from 50 percent of the site, archaeologists are increasingly confident that the wreck is the infamous frigate that terrorized the Caribbean and once blockaded Charleston, South Carolina, for a week before running aground in June 1718.

“We’re not going to find anything that says ‘Queen Anne’s Revenge’ or ‘Blackbeard Was Here,’” says Wendy Welsh, manager of the state-run Queen Anne’s Revenge Conservation Laboratory in Greenville, North Carolina. “You have to use all these little clues.”

Mike Daniel, the sea captain who first located the ship, introduced me to Welsh. Daniel is a successful treasure hunter who, in 1972, helped find Nuestra Señora de las Maravillas—a gold- and gem-laden Spanish galleon that sank off the Bahamas in 1656. But it was Welsh who most evoked the persona of a pirate, wearing skull and crossbones earrings and a galleon-like charm around her neck. She stormed through the lab, peeling tarps off cannons with such ardor that Blackbeard might have welcomed her aboard.

The heavily corroded cannons—some eight feet long and meant to spit six-pound cannonballs—were soaking in various chemical baths to restore them, a process that takes roughly five years. Some cannons that hadn’t undergone chemical treatment were barely recognizable. When a metal artifact corrodes underwater, sand, seashells and other objects adhere to its sides—which then provide attachment points for marine life, such as barnacles. These outer layers, which grow thicker over time, are known as “concretions.” Before breaking them apart, lab workers try to identify what lies beneath with X-rays, but some objects are undetectable. If technicians aren’t careful while cleaning the concretions with air scribes—a type of mini-jackhammer—valuable pieces can be destroyed, especially small ones.

“Once you touch a glass bead, it shatters, and you’re done,” Welsh says.

“Same thing happens with emeralds,” Daniel says.

“I wouldn’t know,” Welsh says a bit wistfully.

Except for a sprinkling of gold dust—less than one ounce so far—no treasure has been found aboard the vessel likely piloted by Edward Teach, the British-born pirate known as Blackbeard. According to 18th-century depositions, Blackbeard—named for his impressive facial hair, which he styled in braids—seized his best and biggest warship from French slave traders in 1717, one hundred miles off Martinique. Capable of carrying about 300 tons and armed with 16 cannons, the vessel carried hundreds of slaves and 20 pounds of gold dust. It was called La Concorde, but Blackbeard, who’d served the crown in Queen Anne’s War against France (1702-13) before going into business for himself, promptly renamed his prize in honor of the English monarch. After offloading most of the slaves and the captured crew, and relieving them of their gold, Blackbeard spent months marauding in the Caribbean, acquiring a miniature navy of smaller boats and amassing a huge crew.

In May 1718, the Queen Anne’s Revenge blockaded the port of Charleston, holding prominent citizens hostage in return for a chest of medicine. After collecting the ransom, Blackbeard retreated to North Carolina, which had plenty of hiding spots in obscure coves and inlets behind the Outer Banks. Alas, in early June, as Blackbeard and his fleet advanced on the sleepy fishing village of Beaufort, North Carolina, the Queen Anne’s Revenge foundered on a sandbar.

The details of how the ship ran aground remain a matter of dispute. Some experts believe Blackbeard was just another victim of the treacherous sandbanks at the mouth of Beaufort inlet, which tend to shift during storms, confounding even modern captains. Others, however, think Blackbeard deliberately abandoned the ship, which was far too large to navigate North Carolina’s shallow sounds, in an effort to downsize his crew (some of whom later testified as much) and travel light, transferring his treasure to the smaller ships in his fleet. Whatever the scenario, the demise of the Queen Anne’s Revenge was what archaeologists call a “nonviolent wreck event,” meaning that the pirates had ample time to offload plunder.

Luckily, the archaeologists have a different notion of treasure. They’ve found hundreds of historical objects including a diminutive signal gun, turtle bones (possible remnants of a favorite pirate food), a pewter syringe, a funnel-shaped spout that served as a urinal and an intact piece of window glass, blue-green and rippling like a sculpture of the sea. The 2010 dive yielded an ornate sword hilt made of iron, copper and an animal horn or antler.

The trouble is, none of these proves the ship’s identity. Though the datable artifacts can be traced to the decades before the vessel’s sinking (any dates after June 1718 would be powerful evidence against the ship’s claim to fame), so far there is nothing conclusive.

By contrast, the wreck of the Whydah Galley, the best-established American pirate ship, which sank in a storm off Massachusetts in 1717, yielded a bell inscribed with the ship’s name. Without a similar trophy, it’s challenging to make an airtight case that Daniel’s discovery is the Queen’s Anne’s Revenge. “We’re trying to get into the minds of piratical characters from 300 years ago with limited historical and archaeological evidence,” says David Moore, an archaeologist with the North Carolina Maritime Museum, in Beaufort, where many of the wreck’s artifacts are on display. But the clues keep mounting.

First, there’s the general location of the wreck, which is consistent with the historical accounts and antique maps that Daniel used in his search. “In the world of shipwrecks, our basic philosophy is that it is where it’s supposed to be,” he says. “Here’s the sandbar, here’s the channel coming in, and in that channel sits the QAR.” Then there’s the sheer size of the three-masted ship, which would have made it an unusual, if not unique, visitor to the little-traveled Beaufort inlet. The boat was also armed to the teeth—excavators have recovered some 225,000 pieces of lead shot and identified at least 25 cannons (though La Concorde carried only 16, the pirates would likely have added some of their own). The guns were apparently kept loaded at all times, a typical scofflaw practice. And then there’s the stuff with which they were loaded. At least one has iron bolts in its bore, and there are other suggestions of deck-clearing ammunition, like the remains of canvas bags full of broken glass, nails and other shrapnel. “A proper Englishman would not do that,” says Jim Craig, the head geologist for the project. “But a pirate is a pirate and he does anything he wants.”

Researchers are also finding potential links to the ship’s past as a French slaver. Manacle-like restraints and glass beads of the sort frequently traded in Africa have been recovered. Divers siphoning sediment from the wreck site have found dustings of gold that might have been part of La Concorde’s cargo. Archaeologists have salvaged several objects inscribed with fleurs-de-lis—a symbol that was often, though not exclusively, associated with France.

But since pirates acquired loot from everywhere, the best clues may be in the bones of the ship itself.

There isn’t much timber left to examine, since wood that isn’t buried deteriorates in salt water. Fortunately, part of the vessel remained covered in sand. When the team recovered a 3,000-pound piece of the stern, they found two draft marks meant to show how much of the vessel was below the waterline. While such measurements were vital to navigation, this ship’s seem curiously off—there are 12.75 inches in between the markings, as opposed to a standard foot. But, Moore realized, 12.75 inches was the French measurement for a foot at that time.

The most compelling argument against the shipwreck being Blackbeard’s is found on a cannon barrel marked rather crudely with three very large numbers–1,7,3–and a slightly smaller 0. If these numbers signify a date, 1730, it would be the death knell for the Blackbeard theory. But researchers say the figure more likely refers to an antiquated weight system or perhaps a catalog number.

Blackbeard lived only six months after the abandonment of the Queen Anne’s Revenge; a Royal Navy lieutenant from Virginia ambushed him at sea and sailed home with the pirate’s head dangling from his bowsprit. The pirate’s legend, though, swashbuckles on. His popular exhibit at the North Carolina Maritime Museum is soon to be supplemented with dozens of never-before-seen artifacts, and Blackbeard—played by Ian McShane—and the Queen Anne’s Revenge will both be resurrected in the latest Pirates of the Caribbean film, On Stranger Tides, due out this spring.

Meanwhile, archaeologists are itching to start work on the largest concretion of all: a huge pile of cannons and anchors still on the seafloor. They hope the mound is big enough to contain preserved material for micro-organic analysis. Bits of food, sediment or insect parts could tie the ship to the Caribbean or Africa. Or perhaps they’ll just discover “some hooks and wooden legs,” jokes Mark Wilde-Ramsing, a state archaeologist working on the project. “Parrot bones, maybe.”

Staff writer Abigail Tucker last wrote about lynx in the February issue.