Saving the Wonders of the Sea of Cortez
December 17, 2012
By Tim Folger, for OnEarth Magazine
Night has fallen on the Sea of Cortez, and it’s so dark I can barely see my three companions, even though they’re just a few feet away. We’re camping on a sandy cove on the craggy western shore of Espíritu Santo Island, an uninhabited nature reserve near the southeastern end of Mexico’s Baja California peninsula. Tonight we have the entire island to ourselves, all 40 sere square miles of it. Eroded volcanic cliffs rise steeply behind us; small waves break gently on the beach — above it all, a vault of stars. A perfect desert-island idyll; no one disturbs our solitude. And that’s not good.
“Every semester I come here to camp with my students,” says Carlos Sánchez Ortiz, who is sitting on a plastic cooler, his feet stretched out in sand that’s still warm on this late August night. “Only once in 20 years has PROFEPA checked on us.”
PROFEPA — short for Procuraduría Federal de Protección al Ambiente — is Mexico’s environmental protection agency; its conscientious but overstretched agents oversee the country’s national parks and other natural refuges. “They found us here one night last year and asked for our camping permits,” says Sánchez Ortiz, a professor of marine biology at the Autonomous University of Baja California Sur in La Paz. “It was 11 o’clock, and I told them I was glad to see them, because this island needs protection. I asked them how many times they came here, and they told me once a week, or sometimes just once a month, because the funding from Mexico City had disappeared. If you look at a map of the Sea of Cortez, you’ll see that many natural areas are listed as protected. But there is almost no enforcement.”
Espíritu Santo is but one of more than 900 islands in the Sea of Cortez. The sea itself — also known as the Gulf of California — extends some 750 miles, from the dried-up Colorado River delta in the north to the resort city of Cabo San Lucas at the southern tip of the Baja peninsula. During the past two decades the Mexican government has created 11 marine protected areas in the Sea of Cortez. The intention was to promote sustainable fishing practices: gill nets and trawling are banned, and a few small areas have been designated as no-take zones, where fishing is completely prohibited, at least in theory. In practice, the laws are largely ignored.
The Sea of Cortez is the world’s youngest sea, having formed 5.6 million years ago when part of the tectonic plate beneath the Pacific Ocean broke away from North America. It is one of the most biologically diverse bodies of water on earth. Jacques Cousteau, the famed French diver and ocean explorer, called it the world’s aquarium. Rare and spectacular marine mammals breed and feed here, including the largest animal that has ever existed — the blue whale — and the smallest member of the marine cetacean family and one of the most endangered, the four-foot-long vaquita, Phocoena sinus. Only 200 or so of these porpoises remain in the wild, all in the northern end of the Sea of Cortez. Nearly a thousand species of fish dwell here, and at least 5,000 invertebrate species — no one knows the true number. Hundreds of bird species nest on the sea’s islands. Some biologists think that the region’s 6,000 recorded species might fall short of the actual total by as much as 30 percent.
For all that remarkable diversity, the Sea of Cortez is a sea in decline. Cousteau might also have called it Mexico’s fish market. Every year fishermen take more than 500,000 tons of seafood from the sea, representing about half of Mexico’s fishing economy. (The Gulf of Mexico and the Pacific account for the rest.) That annual catch counts only the fish brought to market; estimates of unwanted bycatch of fish and marine mammals range wildly, from one million tons to three million tons. The destruction began in the 1930s, when the arrival of outboard motors and gill nets transformed fishing here.
Shrimp trawlers do the most damage. For every pound of wild shrimp caught, trawlers kill as much as 40 pounds of bycatch. Using nets weighted with heavy chains that dig as much as a foot into the sea floor, the trawlers scrape virtually any seabed shallower than 300 feet, dredging the bottom year after year in a maritime version of clear-cutting. The wild shrimp fishery in the northern Sea of Cortez has virtually collapsed. In the last several decades, five species of sea turtle have all but disappeared from these waters.
Thousands of illegal vessels are in operation throughout the gulf, and poaching is common. Honest fishermen struggle to make a living, as I learn when two fishing boats pull up on the beach at Espíritu Santo just as we’re breaking camp on an overcast morning.
Five men arrive in the two pangas, high-bowed, narrow-beamed fiberglass boats popular with Sea of Cortez fishermen. They’re here seeking shelter from the rain that threatens to start at any moment. They’ve barely pulled their pangas onto the beach when the storm hits; warm sheets of rain send us all running for cover beneath a rock overhang at the base of a cliff.
While the rain merges with the sea, one of the men tells us that he’s been fishing in this area for 30 years, since he was a boy, and complains that he now needs a pocketful of permits to fish where he’s always fished. He obeys the law and avoids the protected areas, and as a result his catches are far smaller than they used to be. Before the protected areas were established, he would typically net more than 200 pounds of fish in a couple of days. Now it takes a week. In any case, he says, the protected areas are plagued by illegal fishing, which usually takes place at night. He tells us he knows many fishermen who break the law. Some of them are family members and neighbors. He would never report them, he says, because they’re just trying to make a living. The other four men agree.
Sánchez Ortiz confirms the fisherman’s assessment. Almost without exception, he says, the protected areas in the Sea of Cortez are not rebounding. For the past 14 years, he and his students have been making careful surveys of crucial habitats here, counting the number of species in selected areas almost yard by yard. The data are grim. Recovery efforts, hamstrung by lack of enforcement, have largely failed. “In almost all the Sea of Cortez, even where it is protected, the sizes and numbers of fish today are less than 10 years ago,” he says.
* * *
The Mercado Municipal bustles on a steamy August morning in La Paz. As electric fans whirl overhead and music blares from radios, dozens of workers chop and clean recently deceased denizens of the Sea of Cortez, prepping them for the day’s shoppers.
“You can trace the history of the sea in this market. It is one of the oldest in La Paz,” Sánchez Ortiz tells me as we walk the market’s ocher tiled floors, passing green plastic bins filled with ice and fish. “Twenty years ago you would see mostly yellow snapper and leopard grouper. They are the best to eat. Now they sell more sand perch, tilefish, and others that used to be thrown back.” And all the fish in the market are much smaller than they used to be — the average length of caught fish has decreased by more than 17 inches in the past 20 years. As we pass a glistening display of yellow snappers, none exceeding a foot in length, Sánchez Ortiz pauses, spreads his hands about three feet apart, and says, “I used to see them this big.”
The market is dominated by fish that wouldn’t have appeared on anyone’s plate 10 or 20 years ago. “You can see from looking at the fish here that we’re going deeper into the sea to catch them and fishing further down the food web,” says Octavio Aburto Oropeza, a 39-year-old marine biologist at the Scripps Institution of Oceanography in San Diego. He is also an accomplished photographer, and has spent many hours underwater capturing images of exquisite beauty in the Sea of Cortez. A native of Mexico City, he came to La Paz in 1990 to study marine biology at the university here; at the time, it was the only campus in Mexico with a full-fledged program. He became one of Sánchez Ortiz’s students, and they still collaborate frequently. In 2009 they were part of a research team that conducted an extensive survey of the Sea of Cortez, documenting the effects of overfishing and habitat loss. Fish have completely disappeared from some reefs in the northern part of the sea. The absence of grazing fish may explain why bacteria now cover the reefs, a phenomenon referred to by one of the researchers as the rise of the slime.
For much of the past decade, Aburto Oropeza has been working with scientists in the United States and Mexico to identify habitats that are crucial for the long-term viability of fisheries in the Sea of Cortez. His research suggests a practical and economical conservation strategy: to save the sea, and the livelihoods of those who depend on its bounty, it might be enough to protect — with effective enforcement — a few key clearly defined areas.
Among those essential habitats are mangrove swamps. The Sea of Cortez marks the northernmost extent of mangroves on the Pacific side of the Americas. Mangroves thrive in shallow tidal lagoons, their stilt-like roots often permanently submerged. As a result of evaporation, tidal shallows can have higher salt concentrations than the sea itself. To survive in this arboricidal environment, mangroves have evolved some unique adaptations: their leaves exude excess salt crystals, and some species have snorkel roots, which grow up through the mud to obtain oxygen. At least a third of all the fish and shellfish caught by small-scale fishermen here spend part of their life cycle in the sheltering, rooty embrace of mangrove swamps. The trees also reduce coastal erosion and storm damage, although that fact seems to have been lost on the developers, cattle ranchers, and shrimp farmers who are cutting them down. (Farmed shrimp are typically raised in large rectangular pens, with networks of dikes. Mangroves are destroyed to make room for the pens and dikes, and to make the pens accessible.) Since the 1970s, parts of the Sea of Cortez have lost more than a quarter of their mangrove forests, and nationwide the rate of destruction has accelerated, with some 2 percent of the remaining mangroves across Mexico now being cleared each year.
There’s a large mangrove swamp just 20 miles northeast of La Paz, but Sánchez Ortiz and Aburto Oropeza suggest a roundabout route so that I can see some of the coastal development in the region. We drive southeast and cross the mile-high granite peaks of the Sierra de la Laguna range. Descending to the coast, we pass large homes set in hills above the azure sea; an 18-hole golf course gleams greenly against parched brown headlands. The homes and course are part of a gated community called Bahía de los Sueños, or Bay of Dreams, where many American retirees spend the winter. Aburto Oropeza tells me that the developers chose not to use the bay’s original name, Ensenada de los Muertos, or Cove of the Dead, as it has been called since the late eighteenth century, when some Chinese sailors are said to have died of yellow fever there. We search in vain for a road that will give us better views of the coast, but all the side roads are private, and in some cases guarded. “Twenty years ago this area was pristine,” says Aburto Oropeza. “You could drive on these roads to nice beaches.”
Sánchez Ortiz has arranged for one of the university’s pangas to meet us on the beach near the small town of El Sargento. After boarding the boat, we cruise north along the coast toward the mangrove swamp. It’s a hot, languid afternoon. White-sand beaches backed by umber cliffs cut with plunging, rocky arroyos mark the boundary between desert and sea. There’s not much development visible on this stretch of the coast; the beaches are empty.
“This is the Baja I remember from years ago,” says Aburto Oropeza, as we relax beneath the panga’s blue awning. A short while later the reverie ends when we spot three men in a small skiff. They’re shirtless beneath the scorching sun, working hard, pulling in a net. A fourth man is underwater, breathing from a long hose attached to an air compressor, a practice that has come to be known as hookah diving. “This is very bad,” says Aburto Oropeza, as we pass the fishermen.
Hookah diving is illegal and dangerous — divers frequently succumb to the bends. Despite the risks, though, it has spread rapidly in the Sea of Cortez in the past decade. Hookah divers sometimes spend hours walking along the sea floor, usually near reefs, spearing fish and scooping up shellfish that nets alone can’t reach. Unlike the hookah fishermen we’ve spotted, who are breaking the law in broad daylight, most of these divers work at night, when fish seek shelter and rest in the reefs. The practice amounts to a desperate assault on the last refuges of many species.
Leaving the fishermen in our wake, we soon round the headlands northeast of La Paz and enter Bahía Balandra, the site of a 350-acre mangrove swamp. “Many of the top predator species in the reefs come from the mangroves,” says Aburto Oropeza. The mangroves serve as a nursery for yellow snappers, blue crabs, and other commercially valuable species. After dropping anchor, Sánchez Ortiz, Aburto Oropeza, and I don snorkeling gear and slip into the warm, still water of the swamp.
The water is only a few feet deep; our fins stir up silty clouds as we glide slowly along the outer fringe of the mangrove forest. Underwater, the mangroves’ algae-covered roots are thick and furry and form an almost impenetrable living labyrinth. Small schools of mojarra — slender, silvery fish an inch or two long — swim placidly past my face. When I come up for air, Sánchez Ortiz tells me to push and pull myself as far as I can into the roots. “You should be able to see some yellow snappers here,” he says. He’s right. In the gauzy green light among the roots, a few juvenile snappers dart away from me; they’re bright yellow, maybe four inches long. They began life far offshore, hatching from eggs near the many seamounts — underwater mountains whose peaks don’t breach the surface — in the Sea of Cortez. They’ll spend 10 months to a year in this tidal nursery, feasting on crabs, oysters, and mojarra before heading back out to sea. Without the mangroves, there would be no yellow snappers, many shellfish would vanish, and the fishing economy of the Sea of Cortez would be crippled.
“How much is one hectare of mangrove ecosystem worth?” Aburto Oropeza asks. Four years ago, in a paper published in the Proceedings of the National Academy of Sciences, he and several colleagues gave a precise answer to that question. They studied 13 fishing grounds in the Sea of Cortez and found that the number of fish caught in each area depended on the size of the closest mangrove swamp. “We used a huge database from the national commission of fisheries and aquaculture and some data about mangrove coverage using satellite images,” Aburto Oropeza tells me.
The study was the first to assess the economic value of the country’s mangrove forests. Aburto Oropeza hopes that studies like this, which document the economic benefits of conservation practices, will persuade the government to outlaw highly destructive enterprises that purport to benefit the economy. What is lost, after all, by chopping down a few acres of trees in a swamp? “We were able to calculate that one hectare of mangroves produces about $37,500 worth of fish and shellfish per year,” says Aburto Oropeza. “Every year all these mangroves produce something like 11,000 tons of fishery products for the region. And that represents nearly $19 million a year for the fishing communities of the Sea of Cortez. Now the challenge is to find the political will to protect these resources.”
Perhaps the biggest problem confronting the current conservation effort is that the 11 existing protected areas of the Sea of Cortez are too large to patrol with limited resources. “I was at a meeting in the Yucatán recently where one of the top fisheries scientists for the Mexican government estimated that more than half of all the fish captured in Mexico are captured illegally,” says Rick Brusca, a marine biologist who recently retired as director of conservation at the Arizona–Sonora Desert Museum, in Tucson. “That pretty much sums it up. And I don’t know if the prospects will improve anytime soon.”
Over breakfast one morning in La Paz, I discuss the problem of enforcing Mexico’s environmental regulations with Aburto Oropeza and Carlos Navarro, a wildlife photographer. Aburto Oropeza believes there is an effective way to protect some of the sea’s most important fisheries that would also bring economic benefits. Many species of fish in the Sea of Cortez — and elsewhere in the world — reproduce by forming what scientists call spawning aggregations. A more apt term might be fish orgies. Tens of thousands of fish might swim for hundreds of miles to gather in dense, swirling eddies of courtship and sex, releasing clouds of eggs and sperm. The aggregations are often linked with rising tides and occur during new and full moons at a variety of favored locations, depending on the species — river mouths, seamounts, or reefs.
One fish that spawns in aggregations is the Gulf corvina, Cynoscion othonopterus. Every spring, millions of them flock to the northernmost end of the Sea of Cortez, where the Colorado River emptied into the sea before it was dried up by the thirst of American farms and cities. They spawn during the full and new moons of February, March, and April, just before the strongest tides. After each spawning orgy, the fish depart with the tides, returning two weeks later to spawn again.
“Fishermen know where to go,” says Aburto Oropeza. Over the course of the whole season, they catch as much as 4,500 tons of corvina. Starting in the 1950s, the exploitation of spawning aggregations led to the fish’s commercial extinction; it took 40 years for the species to recover, a recovery perhaps aided by the overfishing of sharks, the chief predator of corvina. Now the corvina aggregations are being plundered once again.
“It’s a recipe for collapse,” says Aburto Oropeza. “There are 10 species that are the most important commercial species for small-scale fishermen in Baja Sur [the southern part of the Sea of Cortez], and eight of them form spawning aggregations.”
He sketches a bar graph on a napkin. “Look,” he says. “This is the annual catch, and this is the percentage of the catch that is related to spawning aggregations.” Fishermen in the Sea of Cortez work year round, but they earn the bulk of their income during the spawning aggregations, when they pull in about 60 percent of their annual catch of these eight species in just three months.
Aburto Oropeza says that in addition to the enforcement problem, the criteria for the sea’s protected areas are too broad and ill-defined to be effective. “The stated goals for the protected areas are to promote research and education and sustainable fisheries,” he says. But the government needs to enact more specific and better-informed policies. The first priority should be the protection of spawning aggregations. Most of the spawning sites are known, and because they are located in small areas, enforcement would be possible. “If you made spawning aggregations part of marine reserves,” he says, “the scenario in the Sea of Cortez would be completely different.”
“If you have only a handful of inspectors, have those inspectors there for those few spawning days,” says Navarro. “It’s a no-brainer.”
If the spawning aggregations and mangroves can be protected, the Sea of Cortez might yet be saved, and the disappearance of species halted. To give me a sense of what has already been lost, Navarro tells a story about an old photographer friend. “He was one of the first to photograph El Bajo, a seamount about an hour from here,” he says. “In 1980 he was looking for hammerhead sharks to photograph. He told me that when he got near El Bajo, he saw a big dark shape floating on the water, like an oil slick. When he got closer, he realized it was a solid concentration of whale sharks, marlin, and manta rays, with their fins sticking out of the water. He saw hammerheads, but there were so many other fish he could barely see them from the surface. I was in the same spot in February . I saw one medium-size grouper and that’s it. No whale sharks, no manta rays.”
* * *
About a hundred miles southeast of La Paz, near the small coastal village of Cabo Pulmo, there are sharks, manta rays, sea turtles, and other species in numbers not seen anywhere else in the Sea of Cortez. That wasn’t the case 13 years ago. In 1999, Aburto Oropeza, working with several colleagues, surveyed the number of species in the waters off Cabo Pulmo. A 27-square-mile marine protected area had been established there four years earlier, and the researchers wanted to see if the area had started to recover. It hadn’t. The total species count hadn’t changed significantly since the park’s creation.
Aburto Oropeza returned to Cabo Pulmo 10 years later for a follow-up study. This time, he was astonished by the changes. “It is incredible, the recovery there,” he says. “In only 10 years the increase in biomass has broken any of the records that we know of in the peer-reviewed literature. The total biomass has increased 460 percent. In terms of top predators, it has increased 1,000 percent in just 10 years. In the past four years we’ve even seen tiger sharks and bull sharks return. Cabo Pulmo is now one of the best marine reserves in the world in terms of biomass of fish per hectare.” (Most of the world’s marine protected areas are far smaller than Cabo Pulmo; the average size is less than four square miles.)
“What that example shows is that the basic productivity of the sea hasn’t been destroyed,” says Sánchez Ortiz. “Our guess is that if you give a place five or 10 years, it will come back.”
The changes are due largely to the efforts of the villagers themselves, many of whom belong to a single extended family, the Castro Luceros. Fearing that their once bountiful fishing grounds were being destroyed by overfishing — and indeed that any fishing in the area might not be sustainable — the villagers began petitioning the federal government more than 20 years ago to establish a marine reserve at Cabo Pulmo. The government eventually granted their request in 1995, setting aside 35 percent of the park as a no-take zone, where all fishing is prohibited, and banning gill nets, trawling, and long lines in the remainder of the park. Many in the village thought the no-take zone was too small and decided on their own to enforce a no-take policy throughout the whole park. The villagers now regularly patrol the waters in their pangas to guard against poaching. Overnight, the hundred or so members of a century-old fishing community voluntarily gave up their way of life. The plan was to remake the village into an ecotourism destination.
“For the first five years it was very hard for our families, because we used to do commercial fishing,” says Paco Castro Lucero, as we stand near his family’s dive shop on the beach at Cabo Pulmo. “Not many people knew about this place, so only a few people came here for snorkeling and diving.” There was no guarantee of success, but the family’s patriarch, Don Jesús Castro, a former pearl diver who died in 2005 at the age of 106, was a fervent conservationist who convinced the community to persevere.
As the reefs off Cabo Pulmo began to recover, word of the wonders to be seen there spread to Cabo San Lucas, the big resort city only 60 miles away. Today there are at least five locally owned ecotourist businesses in the village, and their employees earn much more than the norm for Mexico. “We estimate that ecotourism in the Cabo Pulmo park has an economic benefit for the area of around $700,000 per year,” says Aburto Oropeza.
What remains to be seen, however, is whether this remarkable success can be repeated elsewhere in the Sea of Cortez. Cabo Pulmo is distinctive in many ways. The village is small and socially cohesive, and close enough to two major cities — La Paz and Cabo San Lucas — to make ecotourism a viable alternative to fishing. In addition, it has the sea’s most spectacular coral growths. Few other fishing towns, however well-intentioned, will be able to accomplish much on their own.
“We need policies that can ensure that people who now depend solely on fishing for a living will have some alternative,” says Miguel Cisneros, the former head of Mexico’s National Fisheries Institute. “In some places, there are no opportunities for young people. They go to kindergarten if they’re lucky, maybe elementary school. There is nothing else to do but fish. We need to provide the basic elements — education and alternative livelihoods. Some people don’t even know or understand that there are regulations in place by which they should abide.”
Meanwhile, the future of Cabo Pulmo itself is uncertain. A Spanish company, Hansa Urbana, has plans to build a huge resort just north of Cabo Pulmo. The proposed development, Cabo Cortés, would comprise more than 13,000 homes, more than 30,000 hotel rooms, and a marina for nearly 500 yachts. Construction hasn’t yet started, but the Mexican government has tentatively approved large parts of the plan. A number of environmental groups, both local and international, including NRDC, have been trying to stop the development.
“Basically the developers are proposing to build, in a 15-year period, a large city, another Cancún,” says Aburto Oropeza. “Losing this battle would mean more coastal development without any plans for coherent sustainability of the natural resources in the area. Winning this battle would represent a change where successful stories like Cabo Pulmo might happen in other areas.”
For now, the view from Cabo Pulmo must look much as it did decades ago: a five-mile-long stretch of beach bordered on the north and south by rocky points and surrounded by the peaks of the Sierra de la Lagunas. It’s another blisteringly hot day, so with encouragement from various members of the Castro Lucero family, I rent some snorkeling gear and head into the water with José Cota Nieto, one of Sánchez Ortiz’s grad students. We explore the reefs for two dreamlike hours and see hundreds of fish: spectacular moorish idols, with yellow and black stripes on their narrow flanks; puffer fish, their dark blue bodies covered with white spots; trigger fish; leopard groupers; seahorses. At one point I’m startled by an object the size of a small table that suddenly appears beside me — a sea turtle, a ridley sea turtle, I think. I surface to get Cota Nieto’s attention; I want him to see it. But when we dive again, the turtle has vanished.
This story was originally published by OnEarth magazine.
Photographs by Octavio Aburto Oropeza.
Tim Folger, an OnEarth contributing editor, has been writing about science and the environment for more than 20 years. In 2007 he won the American Institute of Physics science writing award. His work has appeared in Discover, National Geographic, Scientific American, and other magazines.