Big Fish

If the goliath grouper loses its legal protection, will the 800-pounder sink or swim?

This story appears in the July 2014 issue of National Geographic magazine.

Off the coast of southwest Florida, a hundred feet below the water’s surface, a whump rolls through the sea. Another whump follows, like the boom of distant fireworks. It’s coming from the carcass of a drowned ship. Packed into the cracked-open belly of the wreck are a dozen very big—and very audible—fish.

These are Atlantic goliath groupers. They gather on shipwrecks and reefs to eat and socialize. At up to 800 pounds and nine feet long, they sport jutting jaws and giant palm fronds for fins and are mottled and spotted in earth tones. They announce their presence to encroaching creatures by squeezing their swim bladders, the air sacs that help keep them afloat. Whump. Whump. WHUMP!

Nowadays when it comes to goliaths, people are the noisy ones. Atlantic goliaths used to be numerous and widespread, inhabiting the waters of the southern United States, the Caribbean, and Brazil by the tens of thousands. But after years of being speared and hooked by the boatload, their numbers dwindled to an unknown low, perhaps below a thousand. The Florida population is now rebounding, and fishermen, biologists, and local officials are raising their voices over whether the animals have recovered enough to shed their legal protection from people wielding spearguns and fishing lines.

Chris Koenig of Florida State University has been catching goliaths for decades, but not to bring them home as fillets or trophies. With the help of some strong assistants, he hooks goliaths and wrestles them on board a small boat to measure them, remove a cartilaginous fin ray for DNA and age tests, sample the stomach contents for diet studies, and check reproductive organs for signs of spawning. Each fish gets a tag beneath its skin before the scientists slide the animal back into the sea. Tracking his catch-and-release fish, Koenig has been able to pile up information on where and when they show up and how healthy each one is. He and his wife and colleague, Felicia Coleman, who helps manage the slew of data, hope to get a handle on the current status of the species, Epinephelus itajara.

The goliath’s own behavior contributed to its population drop. “Ordinarily these fish don’t move a whit; they are glued to the reef,” where food and shelter are plentiful, Koenig says.

That makes them easy targets. “We used to shoot goliaths all the time,” says 86-year-old Frank Hammett, who spent much of his 20s with speargun in hand. “In Palm Beach you could see them sitting on the bottom in a hundred feet of water. The reefs were covered with them. There might be a hundred in one spot or a wall of them—something you don’t forget! I’d shoot one or two, get eight cents a pound for them. Did that for 15 years or more.”

For a while the grouper’s commercial appeal was regional—in the Florida Keys goliath grouper with black beans and rice was a delicacy—but when other fish stocks waned in the early 1980s, goliaths landed on menus everywhere. They were also a recreational favorite; sportsmen loved overpowering the giants. Many thousands died as trophies. Long-lived and slow to mature, the species simply couldn’t keep up with the slaughter. It teetered on the edge of extinction.

But it didn’t fall. In 1990 the goliath, identified as endangered, received legal protection in the southeastern U.S. The fish have been slowly rebuilding their population ever since—and attracting scuba divers, who delight in swimming with the immense but nonthreatening fish. The biggest recovery—perhaps as many as thousands of fish—has been off southwest Florida where the mangrove forests, the home of the juveniles, remain thick.

As often happens in the world of conservation, there are two distinct sides on the issue of goliaths. Still considered critically endangered in much of their range, goliaths in Florida remain legally off-limits. “The political pendulum has swung so far toward protection that you can’t even touch or look at one,” says Key West City Commissioner Tony Yaniz. “You’re better off getting caught with bales of marijuana than with one of these fish.”

Yet many fishermen insist the animal has returned in droves. And they complain that the big fish interfere with business. “We have goliaths taking legal grouper and snapper right off our lines, over and over,” says commercial fisherman and guide Jim Thomas. “Lobsters too. It’s such a waste.” He is one of many who want to be able to fish for goliaths—even just a few annually—to thin out the alleged thieves. It doesn’t have to be a one-sided benefit, Yaniz adds. Why not have the fishermen contribute to answering the conservation questions by providing data on numbers and sizes of fish? “They’re the ones out there every day, with eyes on the water. They can really help us figure out where the species stands.”

Conservationists think the fishing community is off base. Koenig and other non-fishermen with “eyes on the water” strongly dispute the claim that groupers are sucking up fishermen’s haul. Studies have repeatedly shown that the lumbering goliaths feed almost exclusively on small, slow targets (crabs, not lobsters, make up more than half their diet).

Koenig says that giving permission to fish for goliaths in Florida where numbers are up could hamper overall recovery. These fish mostly stick close to the same shallow reefs, rocky ledges, and wrecked ships. “As homebodies,” he explains, “goliaths are already reluctant to relocate.” So if you thin out the most crowded areas, the remaining goliaths have even less reason to recolonize places where the species has died out. And that means recovery won’t be as widespread as it could be.

Koenig and Coleman have found that the only time goliaths really move far is for spawning. “When it comes time to mate, they will travel great distances to get to spawning sites, nearly 300 miles in some cases,” says Koenig. “They might cover 25 miles a day in a beeline.” Fish from far and wide, maybe from the entire Atlantic seaboard, congregate offshore near shipwrecks and reefs, sidling together in bullet-shaped masses, bumping and nuzzling and sounding off in the dark of night as they send up sperm and eggs to build the next generation.

However successful their mating, a return to historic high numbers may be just a dream for the big fish. Koenig says exposure to mercury is having “an insidious toxic impact” on the animals. “The adults have actual pathologies—lesions in the liver—from the levels of mercury,” he says. Not only might that be partly to blame for the fish’s decline, but also it means we shouldn’t be eating these things. “If you were to catch anything over about four feet long,” says Don DeMaria, a former commercial fisherman who assists with conservation efforts, “you would have to throw it back anyway.” The mercury, he says, “makes it inedible.”

The future of goliaths is also tied up in those mangrove nurseries, where the fish live around the trees’ tangled roots until they are about five years old. Coastal development, agriculture, and pollutants threaten these shallow-water habitats. The current trajectory suggests 20 percent losses of remaining U.S. mangroves in the next 50 years—devastating for young, developing goliaths, which are already reeling from unusually cold winters that took out thousands of the fish from their juvenile habitat throughout South Florida.

Ultimately fishermen and biologists and even government officials want the same thing: a grouper population big and vigorous enough to keep divers coming and to weather a few hooks in the water without collapsing. While the debate rattles on, the goliaths in question continue booming beneath the waves.

The big fish, too, just want to be heard.