Menus Subscribe Search

The Perils of Being Selfish With Shellfish

• December 01, 2009 • 5:00 AM

Bandits, then locals, broke the rules in self-governed marine reserve, marring what had been a heart-warming conservation success.

It was good news when scientists in Puerto Peñasco, a fishing and tourism hub in Baja California, found proof for the first time of the rapid “reseeding” effects of marine reserves — how a no-fishing zone can replenish fish stocks by exporting babies beyond its boundaries.

The Puerto Peñasco divers were worried about the declining stocks of snails and scallops, the bread and butter of their trade. So, beginning in 2001, they worked closely with researchers to design, set up and monitor three de facto marine reserves where fishing was banned. The no-fishing zones extended along 11 miles of rocky coast and around San Jorge Island, 20 miles offshore in the northeastern Gulf.

Within a year, there were big increases in the abundance of juvenile rock scallops and black murex snails both inside and outside the reserve boundaries. The bigger and older the shellfish got inside the reserve, the more larvae, or babies, they produced, and the more they drifted with the current, quickly reseeding the depleted areas where fishing was allowed.

The reserves extended over 30 percent of the fishing grounds, but the local cooperative of about 22 divers could see that it was beneficial. They volunteered their time to count scallops and snails underwater. They kept an eye on each other, too, taking occasional trips to the island to see if anyone was cheating.

During the first two years of the reserves, there were only 13 violations of the fishing ban out of 2,000 local diving trips from Puerto Peñasco. Nobody wanted to risk being ostracized. News of the thriving shellfish stocks spread along the coast. The Mexican government recognized the divers with a Presidential Conservation Award.

“Things were going so well,” said Richard Cudney-Bueno, who helped design the Puerto Peñasco reserves as an adjunct biology professor at the University of Arizona School of Natural Resources and a researcher at the University of California, Santa Cruz Institute of Marine Sciences.

And then the roving bandits came.

They arrived in a handful of boats from 200 miles away, and they started poaching in the reserves that had been maintained based on trust at San Jorge Island. There was nothing the locals could do. The Mexican government had never formally recognized the fishing ban, and nobody had a legal right to throw out the newcomers.

The locals weren’t going to stand by and let others reap the benefits of their investment at San Jorge. So, they joined in the poaching, and it spread from the island to the coastal reserves in a free-for-all.

Within a month, the local populations of scallops and snails plummeted by half as the divers took in big hauls, driving down the market price. By the end of two months, the shellfish stocks had dropped to pre-closure levels.

“The whole thing got wiped out due to disruption of the social structure that had supported it,” said Peter Raimondi, a University of California, Santa Cruz biologist who collaborated on the study. “Scientifically, it was really interesting, but for the people who experienced it on the ground, it was terrible.”

How Reserves Work
The establishment of marine reserves is typically controversial and fraught with conflict. Environmentalists seek the conservation benefits of “underwater parks,” but the fishermen don’t see what’s in it for them. Where’s the proof, they want to know, that reserves can actually replenish stocks elsewhere?

In their groundbreaking study of the Puerto Peñasco reserves, published this year on the PLoS ONE blog, Cudney-Bueno, Raimondi, William Shaw of the University of Arizona and their colleagues in Mexico, describe how they were able to predict and then confirm the rapid effects of the dispersal of fish larvae outside the reserves.

By tracking local currents in the Gulf of California and calculating how far the wandering larvae would travel, the scientists pinpointed exactly where the larvae, now grown to little scallops, would eventually attach to the rocky ocean bottom. They predicted, correctly, that it would be about a 10-day trip for the floating larvae to locations between 12 and 30 miles away.

The divers counted young shellfish in the “reseeding” locations and inside the reserves both before and two years after the fishing ban went into effect. The scientists found that the density of juvenile rock scallops increased more than 40 percent inside the reserves and more than 20 percent in fishing areas outside the reserve boundaries. The density of black murex snails in fishing areas increased threefold.

Robert Warner, an evolutionary ecologist who helped design a 318-square-mile network of marine reserves around California’s Channel Islands, the largest such network off the continental United States, called the Puerto Peñasco study “an important contribution to the marine reserve literature.”

“It shows a rapid increase in juvenile settlement in areas downstream from reserves, after only two years,” Warner said.

As previously reported by Miller-McCune, local fishermen were engaged in the monitoring efforts at the Channel Islands, just as they were at Puerto Peñasco.

But there the similarity ends. The Channel Islands marine reserves are vigorously enforced by the National Park Service, National Marine Sanctuary, U.S. Coast Guard and California Department of Fish and Game. These agencies patrol the reserve network by air, by sea and on land. The park alone spends about $350,000 per year on enforcement.

As many as 200 fishermen get verbal or written warnings or citations every year at the Channel Islands, park officials said. In addition, the patrols stop more than 1,000 boats yearly to hand out educational materials and deter them from fishing in the reserves.

A Happy Ending
Belatedly, the Mexican government is giving Puerto Peñasco some support.

In a before-and-after study published on the PLoS ONE blog this year, Cudney-Bueno tells how the government in 2006 finally gave the diving cooperative exclusive rights to harvest rock scallop in their fishing grounds. Such formal Mexican fishing “concessions” are rare, and Puerto Peñasco’s was the first in the Gulf of California.

Today, the shellfish stocks are building back up and the diving cooperative is working with researchers to design a management plan, backed by the government, that will include permanent seasonal closures and no-fishing zones for rock scallop and quotas in areas where fishing is allowed. It will give them even more of a buffer than they had before, Cudney-Bueno said.

“It’s just crucial to have control over the fishing grounds,” he said. “The divers know that leaving a place untouched for some time will only lead to an increase in resources. People really can manage their own regions, but if you don’t have the umbrella backup, it’s very hard to control.”

The Mexican government does not have the resources to regularly patrol reserves in the Gulf. But next time, if the bandits come, the Puerto Peñasco divers can legally call on the local port authority to deal with them.

The story of Puerto Peñasco’s success, failure and success has given a boost to fishery protection elsewhere in the northern Gulf, with funding from the David and Lucile Packard Foundation. In Bahía de los Angeles and Bahía de Kino as well as Puerto Peñasco, fishermen are working with researchers to protect not only scallops and snails, but also stocks of crabs, lobsters, sea cucumber and groupers.

“The pie has been sliced in too many pieces in the Gulf,” Cudney-Bueno said. “Some communities are really taking things into their own hands. There’s a sacrifice in establishing reserves, absolutely. But there’s so much belief in the resilience of the system.”

Sign up for our free e-newsletter.

Are you on Facebook? Become our fan.

Follow us on Twitter.

Add our news to your site.

Melinda Burns
Former Miller-McCune staff writer Melinda Burns was previously a senior writer for the Santa Barbara News-Press, covering immigration, urban planning, science, and the environment.

More From Melinda Burns

A weekly roundup of the best of Pacific Standard and PSmag.com, delivered straight to your inbox.

Recent Posts


July 31 • 4:00 PM

Thank You for Your Service: How One Company Sues Soldiers Worldwide

With stores near military bases across the country, the retailer USA Discounters offers easy credit to service members. But when those loans go bad, the company uses the local courts near its Virginia headquarters to file suits by the thousands.


July 31 • 2:00 PM

A New York State of Fracking

Court cases. A governor’s moratorium. Pending health study. A quick guide to the state of fracking in New York.


July 31 • 11:17 AM

How California Could Power Itself Using Nothing but Renewables

We don’t need fossil fuels.


July 31 • 8:00 AM

Should Athletes Train Their Memories?

Sure, but it probably won’t help.


July 31 • 6:00 AM

Universal Basic Income: Something We Can All Agree on?

According to Almaz Zelleke, it’s not a crazy thought.


July 31 • 4:00 AM

Medical Dramas Produce Misinformed, Fatalistic Viewers

New research suggests TV doctor dramas leave viewers with skewed impressions of important health-related topics.


July 30 • 4:00 PM

Still the World’s Top Military Spender

Although declining in real terms, the United States’ military budget remains substantial and a huge drain on our public resources.



July 30 • 2:04 PM

The Rise of the Nuisance Flood

Minor floods are afflicting parts of Maryland nearly 10 times more often than was the case in the 1960s.


July 30 • 2:00 PM

The (Mostly Awful) Things You Learn After Investigating Unpaid Internships for a Year

Though the intern economy remains opaque, dialogue about the role of interns in the labor force—and protections they deserve—is beginning to take shape.


July 30 • 12:00 PM

Why Coffee Shortages Won’t Change the Price of Your Frappuccino

You’re so loyal to Starbucks—and the company knows it—that your daily serving of caffeine is already marked up beyond the reach of any fluctuations in supply.



July 30 • 10:00 AM

Having Difficult Conversations With Your Children

Why it’s necessary, and how to do it.


July 30 • 8:00 AM

How to Make a Convincing Sci-Fi Movie on a Tight Budget

Coherence is a good movie, and its initial shoot cost about the same amount of money as a used Prius.


July 30 • 6:00 AM

Are You Really as Happy as You Say You Are?

Researchers find a universal positivity bias in the way we talk, tweet, and write.


July 30 • 4:00 AM

The Declining Wage Gap for Gay Men

New research finds gay men in America are rapidly catching up with straight married men in terms of wages.


July 30 • 2:00 AM

LeBron James Migration: Big Chef Seeking Small Pond

The King’s return to Cleveland is a symbol for the dramatic shift in domestic as well as international migration.


July 29 • 4:00 PM

Are Children Seeking Refuge Turning More Americans Against Undocumented Immigrants?

A look at Pew Research Center survey data collected in February and July of this year.


July 29 • 2:00 PM

Under Water: The EPA’s Ongoing Struggle to Combat Pollution

Frustration and inaction color efforts to enforce the Clean Water Act.


July 29 • 12:40 PM

America’s Streams Are Awash With Pesticides Banned in Europe

You may have never heard of clothianidin, but it’s probably in your local river.


July 29 • 12:00 PM

Mining Your Genetic Data for Profit: The Dark Side of Biobanking

One woman’s personal story raises deep questions about the stark limits of current controls in a nascent industry at the very edge of the frontier of humans and technology.


July 29 • 11:23 AM

Where Should You Go to College?


July 29 • 10:29 AM

How Textbooks Have Changed the Face of War

War is more personal, less glorious, and more hellish in modern textbooks than in the past. But there’s still room for improvement.


July 29 • 10:00 AM

The Monolingual American: Why Are Those Outside of the U.S. Encouraging It?

If you are an American trying to learn German in a large German town or city, you will mostly hear English in return, even when you give sprechen your best shot.


Follow us


Subscribe Now

The Rise of the Nuisance Flood

Minor floods are afflicting parts of Maryland nearly 10 times more often than was the case in the 1960s.

America’s Streams Are Awash With Pesticides Banned in Europe

You may have never heard of clothianidin, but it's probably in your local river.

How Textbooks Have Changed the Face of War

War is more personal, less glorious, and more hellish in modern textbooks than in the past. But there’s still room for improvement.

NASA Could Build Entire Spacecrafts in Space Using 3-D Printers

This year NASA will experiment with 3-D printing small objects in space. That could mark the beginning of a gravity-free manufacturing revolution.

The Big One

One in two full-time American fast-food workers' families are enrolled in public assistance programs, at a cost of $7 billion per year. July/August 2014

Copyright © 2014 by Pacific Standard and The Miller-McCune Center for Research, Media, and Public Policy. All Rights Reserved.