The high-stakes quest to save a behemoth, croaking fish

The endangered totoaba is fished illegally in Mexico for its swim bladder and sold in China to make medicinal soup. What can combat this lucrative trade?

By Dina Fine Maron
Published 15 Sept 2022, 15:30 BST
A Mexican fisherman examines his day’s catch from the Gulf of California. Fishermen working out of ...
A Mexican fisherman examines his day’s catch from the Gulf of California. Fishermen working out of San Felipe often illegally use gillnets to target the area's fish, including totoaba, a protected species that Mexico considers endangered.

We’ve come into the desert in search of fish. Dead ones. The rank, briny smell slamming my olfactory receptors suggests we must be getting close. Photographer Kirsten Luce and I move toward the stench.

We’re at an isolated, unofficial trash dump surrounded by everything from tires and toilets to plastic bottles and electronic equipment. The blue water of the Gulf of California shimmers at our backs as the fisherman who agreed to bring us here scans the detritus.

“There! That’s totoaba,” he says, pointing to a large mound. Amid the trash, more than a dozen huge, rotting fish carcasses spill out from a flowered bed sheet. Shiny silver scales cover some of the bodies; other remains are nothing more than heads and fins.

More totoaba carcasses lie nearby. The fisherman points to a slit along one body where he says totoabaeros, totoaba poachers, had extracted the animal’s swim bladder. When filled with air, the organ—known also as maw, or buche—helps maintain buoyancy. But the bladders are prized in China and other Asian countries, where they’re served in soup for supposed medicinal properties, such as nourishing the liver and kidneys, improving the skin, and enhancing blood circulation. They’re sold by weight—one kilogram, roughly two pounds, may sell for as much as £86,000, according to some reports.

Fishermen dispose of the carcasses of illegally caught totoaba at an isolated dump site. The swim bladders of these massive fish are sold in China for unproven medicinal benefits, although Mexico banned totoaba fishing in 1975.
Photograph by Kirsten Luce

Found only in the Gulf of California, totoaba are the biggest in a family of fish known as croakers—so named because of the sound they can make when air whooshes in and out of that swim bladder. They can live into their mid-20s, weigh up to 300 pounds, and grow to more than six feet. 

Mexico classifies totoaba as endangered and in 1975 made it illegal to catch them. Two years later, totoaba also became the first fish prohibited from global trade under CITES, the treaty that regulates international wildlife sales. And in 1979, the United States, once a major consumer of totoaba meat, added them to its endangered species list, making it illegal to take, possess, transport, or sell the fish.

The carcasses at the dump, although large, aren’t full-size. With increasing demand for maw since about 2010—when a related species in Chinese waters, the yellow croaker, had been fished to the brink of extinction—fewer totoaba, it seems, are fully grown before they’re caught.

“We shouldn’t be seen here,” our guide says urgently. Luce hurriedly takes a few final photos, and we leave the dump.

He'd asked us not to name him because he’s afraid. As demand for totoaba maw has soared in China, Mexican drug cartels muscled into the business, according to Clare Perry, a wildlife trade policy expert with the London-based Environmental Investigation Agency.

Trucks haul boats loaded with gillnets into the water in front of San Felipe’s promenade. The town’s marina has a boat ramp, but some fishermen prefer to use this beach where permits are less likely to be scrutinized.
Photograph by Kirsten Luce

The cartels act as intermediaries for Asian buyers. They routinely set industry prices, dictating the volume of the catch, and may threaten—or kidnap—family members to force fishermen or seafood processors to comply with their demands. Organised crime also has made inroads into the country’s legal seafood industry, according to recent research by the Brookings Institution’s Vanda Felbab-Brown, who studies the wildlife trade, drug trafficking, and other organised crime.

Fishermen say that hundreds—if not thousands—of boats illegally ply the waters off San Felipe, many seeking totoaba but also competing for shrimp, corvina, and sierra (Spanish mackerel). According to Alberto García Orozco, 73, a fisherman and seafood processing plant owner, it was possible to make as much as £13,000 for a totoaba bladder about a decade ago when prices were at their highest. Prices have dropped recently, both because the cartels are flooding the market and because maw is now also sourced from croaker species off the coast of Bangladesh, India, Papua New Guinea, and elsewhere.

Yet in June 2020, authorities in Hong Kong made the biggest totoaba maw seizure in decades: bladders from 270 fish worth more than £2.5 million. And last year, Hong Kong inspectors discovered another massive shipment bound for Vietnam.

Surprisingly perhaps, months after the 2020 seizure, the International Union for Conservation of Nature, which publishes a list of species threatened with extinction, changed the designation for totoaba from “critically endangered” to “vulnerable.” The downlisting was based on a better understanding of how dire the situation had been decades ago, but it “doesn’t represent an improvement in status,” says Kristin Nowell, a member of the peer-review group for that decision and the executive director for Cetacean Action Treasury, a nonprofit that works in San Felipe to support conservation efforts. It’s a decision made without the benefit of a reliable population census, she adds.

The fish and the porpoise

Mexico’s history of totoaba protections is inextricably linked to measures to save the vaquita, a critically endangered porpoise also found nowhere else but the Gulf of California. Scientists estimate that no more than 10 vaquita survive today. Gillnets of various mesh sizes—especially the large ones used to catch totoaba—are their most pressing threat.

Photograph by Kirsten Luce

In 1993, Mexico declared a 3,700-square-mile portion of the upper gulf a bioreserve and limited fishing, but vaquita numbers continued to plummet. The government later designated a much smaller swath of the bioreserve frequented by vaquita—a rectangle of less than 200 square miles—as a “zero tolerance area” off-limits to all boats. During just one day in the autumn of 2021, however, international scientific observers spotted 117 pangas—as the local fishing boats are called—within the forbidden waters. 

Conservation groups and the U.S. government, among others, have long criticised Mexico for not doing enough to combat the maw trade—and to safeguard the vaquita. In February, the U.S., citing concerns about Mexico's totoaba and vaquita, filed the first formal environmental complaint under the U.S.-Mexico-Canada free trade agreement. If the issues aren't resolved, Mexico could face trade sanctions. Mexico says it’s committed to the terms of the treaty.

Mexico banned gillnets in 2015, but from San Felipe's tourist boardwalk, which looks out over the bioreserve, Luce and I watched the comings and goings of dozens of pangas stacked high with gillnets. Either anchored or dragged behind a boat, the nets allow the head of a fish to pass through but entangle its gills when it tries to escape. Their mesh size varies according to the size of the intended catch: smallest for shrimp and largest (about the same as a soccer net) to snag totoaba.

San Felipe fishermen who have used gillnets for generations say no alternative exists for them to earn a viable living from the sea.
Photograph by Kirsten Luce

Our guide at the desert dump had told me that fishermen can’t earn a living using only legal methods, such as a hook and line, let alone cover the cost of boat fuel—about £170 a day in his case. To make any profit—even with permitted fished species—gillnets are essential, he said.

“If we go with lines or traps or something like that, we may get nothing, or just like two to three kilos of shrimp. What’s the business there? It’s impossible!” That amount of shrimp would bring about $30 [£26], he says. “The only technique in the gulf is the gillnet! That’s the truth.”

How deadly gillnets are for vaquita—and other marine animals, such as sharks, turtles, and whales—is hotly contested in San Felipe and other areas, including off California, where they’ve been used for generations.  

Orozco claims that only the largest-mesh nets are a threat to cetaceans such as vaquita. Smaller-mesh ones, used to snag shrimp or other fish, can’t harm them, he says. Similarly, during a 2022 CITES mission to San Felipe to check on the status of totoaba and vaquita, Mexican government representatives told the group that shrimp gillnets couldn’t endanger vaquita and also claimed, incorrectly, according to CITES documents, that such nets are allowed.

Julio César Mercado, who buys sustainably caught fish, shows fishermen how to stab a corvina in its brain to paralyze it and cause brain death. This ike jime method is considered to be humane and improve the taste of the fish. Mercado is willing to pay a premium price for fish caught with a hook and line rather than a net.
Photograph by Kirsten Luce
Corvina killed using the ike jime method are drained of their blood, making their flesh appear whiter and reducing bacteria, according to Julio César Mercado.
Photograph by Kirsten Luce

But research has found that all mesh sizes can, and have, trapped vaquita. By the time fishermen pull nets up, any entangled porpoise invariably will have drowned. 

Mexico’s CITES office did not respond to a request for comment on government statements made during the mission trip.

To reduce vaquita bycatch, biologist Valeria Towns, project coordinator for the Mexican nonprofit Museo de la Ballena (“whale museum”) and a National Geographic Explorer, says her organisation, along with Sea Shepherd, an international marine conservation and activist group, search for and remove totoaba gillnets.

In 2015, Mexico started paying fishermen in San Felipe not to fish, reasoning that the reprieve would give enough time for vaquita-friendly fishing gear to be developed. The program was controversial, but fishermen I spoke to said the money was enough to live on and that they’d stopped fishing. But three years on, when Andrés Manuel López Obrador became Mexico’s president, his administration stopped the payments, and fishing resumed.

As for vaquita-friendly fishing gear? “That never happened,” Towns says. Any alternatives are still in the prototype stage.

When I asked Roberto Aviña Carlín, who heads Mexico’s wildlife agency about the continuing use of illegal gillnets, he shrugged and said, “Local people want to work.”

Are there viable alternatives to gillnets?

Towns’s nonprofit is testing other fishing methods and connecting fishermen with buyers willing to pay more for legally and sustainably caught fish—at least on a small scale. “What fishers say is they go out with nets, and their yield is so high there’s no way any alternative gear will be comparable to the yield of the gillnet,” she says. Indeed, she says, prices for sustainably caught fish would have to “go up three times, so that’s not easy.”

One morning, Luce and I join a workshop for three fishermen organised by Daniel Arellano, a biologist with Pesca ABC, a local conservation nonprofit dedicated to supporting alternative fishing methods. Julio César Mercado, a sustainable catch trainer and buyer, leads the training.

Farmed juvenile totoaba brought from a university hatchery are released into the Gulf of California at San Felipe as part of an ongoing effort to replenish wild populations.
Photograph by Kirsten Luce

The aim today, Arellano says, is to teach the fishermen ike jime, a Japanese method of killing fish by destroying their brain, which is said to improve the taste of the meat by preventing the release of stress hormones that otherwise flood the body. Proponents say ike jime also lessens the fish’s suffering. “If done quickly and efficiently, it is considered a humane way of killing fish,” says Lynne Sneddon, an expert on how fish feel pain at the University of Gothenburg, in Sweden.

Mercado works for Sargazo, a company that sells sustainable foods to high-end restaurants in Mexico. For a popular fish such as corvina, he says, he’d normally pay 25 pesos a kilogram (about £1 for just over two pounds), but he says he’d willingly pay twice that for fish caught by hook and line and killed by ike jime. The fish are tastier, whiter, and have less bacteria, he says, making for a high-value product “killed humanely.”

Once our panga reaches deeper waters, Rafael Sanchez, the captain, casts his line, and within minutes, he reels in a wriggling, silver corvina, which he hands to Mercado. One of the fishermen takes a video with his phone. The fish flops back and forth as Mercado holds it down with one hand, then stabs it behind its eyes with a metal spike—the first step in ike jime. He makes several incisions along the body to bleed the fish. Then quickly and deftly, he runs a wire from an incision by the tail under the skin along its spinal cord to shut down its nervous system, done to halt metabolic processes that could taint the taste of the flesh.

Students studying aquaculture at the Autonomous University of Baja California, in Ensenada, conduct a totoaba census at this offshore fish pen in San Felipe where juveniles are bred.
Photograph by Kirsten Luce

After about two hours, the trio has landed 14 corvina and three other fish for a total weight of roughly 65 pounds. That meant Mercado owed the whole group about £60, though they’d all agreed previously that today’s payment would go to Sanchez, who was lending his boat.

Days later, I asked a gillnet fisherman in town how much corvina he’d catch in two hours. Between two and four tons, he said.

Given that disparity, Towns says, “we should pay them a hundred pesos [roughly £4] for each kill of corvina,” which would make it more financially feasible to fish without nets.

Replenishing totoaba in the wild 

Conal David True has been working for more than 25 years to perfect captive breeding of totoaba in Mexico with the aim of replenishing wild stocks and supporting a legal trade in farmed and, eventually, wild fish. He runs a hatchery at the Autonomous University of Baja California, in Ensenada, and his fish or their offspring are now on restaurant menus throughout Mexico. His efforts, alongside those of commercial aquaculture businesses, have led to the release of roughly 500,000 totoaba into the wild since the 1990s.

On a San Felipe beach, Luce and I watch as True directs scientists, students, and others carrying plastic buckets filled with juvenile totoaba—not yet a year old and about seven inches long—to the water. They’re releasing 20,000 raised at his hatchery. By mid-morning, the volunteers and government officials who have come for the event have sweaty brows and red faces, but the atmosphere is ebullient, with smiling faces, congratulatory speeches, and applause.

“I try to get them as big as possible and then do a release,” True says.

College students in an offshore aquaculture class supervised by instructor Raul Herrera Gutierrez (far left) use nets to scoop up captive totoaba to weigh and count them.
Photograph by Kirsten Luce

It’s unclear how the introduced fish fare in the wild. Luis Enriquez, a scientist who works with True, has analysed more than 3,000 totoaba swim bladders seized by U.S. and Mexican authorities for DNA markers common to captive-raised fish. The tally: only 12.

Nevertheless, he says, that’s promising: “They are reaching ages of sexual maturity.” It shows that the juveniles are surviving to adulthood, adding that one was 13 years old and several others were seven or eight. (Wild totoaba are fully grown at six or seven years.) He and colleagues are writing up the findings, but because the poaching cases remain open in the courts, he says they’re still waiting for clearance to publish.

Not long before my visit to San Felipe, Mexico-based Earth Ocean Farms—the largest private company that breeds totoaba in captivity—introduced a proposal at a CITES meeting to sell farmed totoaba to international buyers. Under the treaty, even certain captive-bred species require additional approval to be sold commercially on the global market.

The U.S. and Israel (which represented Europe at the meeting), among others of the 180-plus signatories to CITES, opposed the idea. Conservation and wildlife crime experts worried that it could lead to the laundering of wild totoaba and spur greater demand for maw in China. 

Sales of totoaba meat were ultimately approved but not swim bladders. Alex Olivera, a senior scientist and Mexico representative for the environmental nonprofit Center for Biological Diversity, still opposed the decision. “It’s easy to launder the filets and put some illegally caught ones there,” he says.

Who would buy farmed totoaba meat remains uncertain. The CITES representative from the U.S.—once the main meat consumer—said the country wouldn’t authorise imports. Pablo Konietzko, the CEO of Earth Ocean Farms, told me after the summit that they’re still “far away” from finding buyers and declined to name any country or company that has expressed interest. Europe, Asia, and Latin America are all “possible candidates,” he said.

This young captive-raised totoaba being evaluated and returned to a pen likely will end up on a dinner plate in a Mexican restaurant.
Photograph by Kirsten Luce

Will Mexico legalize totoaba fishing? 

“Totoaba is the main reason this town exists,” says Lorenzo García Carrillo, the leader of San Felipe’s largest fishing federation, as fishermen stream in and out of his crowded office one morning, socializing and talking business. Totoaba fishing attracted many settlers during the 1920s with the promise of an easy, legal catch and good money, and many of today’s fishermen are their descendants. The town boasts a large totoaba statue.

Mario García, a third-generation fisherman, invites me to sit with him at his kitchen table one evening. He pulls out a decades-old calendar and flips to a page with a sepia photo of someone pumping gas into a car. He points to the caption, which notes that Alfredo García—his grandfather—had opened the first gas station in town. He’d done so well fishing for totoaba, shrimp, and turtles that he’d been able to open the business, García says. It’s different today, he adds, because competition for depleted stock is so intense.

García has two pangas and goes out every day, weather permitting—sometimes leaving before dawn and unloading his fish late into the night. He says his catch varies widely and depends in part on the migration patterns of his targets—mainly shrimp, corvina, and sierra. The only respite comes in the summer when it’s too hot to fish. Anyway, he says, there are too few to be had at that time of year. Fishermen call this slow time piojo (“louse”), when they scratch their heads wondering where the money will come from.

Roberto Aviña Carlín, the official who directs Mexico’s wildlife agency, says one way to help struggling fishermen would be to legalise a regulated hook-and-line totoaba industry. Mexico is maybe “five years away” from that, he says. “People need to change away from their nets.”

Legalising the trade of any threatened species has long been controversial. Opponents point to elephant ivory as an example of how some legal trade in wildlife products likely has increased—not reduced—demand, resulting in more animal killings.

Vanda Felbab-Brown, the crime expert at the Brookings Institution, says any such initiative would be complicated. “Good and persistent law enforcement,” would be essential, and Mexico would still have to confront the problem of gillnet use for a variety of fish and repercussions for the vaquita. “Legalising alone will not stem the illegal trade,” she says.

“I don’t think the totoaba will be safe until poaching for its bladder stops, and that’s the problem,” says Miguel Cisneros-Mata, who co-wrote the 2020 IUCN totoaba report and studies fish demographics at the National Institute of Fisheries and Aquaculture Mexico. “How can we do that? I don’t know,” he says.

The National Geographic Society supports Wildlife Watch, our investigative reporting project focused on wildlife crime and exploitation. Read more Wildlife Watch stories here, and send tips, feedback, and story ideas to Learn about the National Geographic Society’s nonprofit mission at


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