Andrés Albonigamayor stares down at the red deck of his fishing boat as the last albacore are unloaded. It’s two hours before sunrise on the wharf of Bermeo, a town in Spain’s Basque Country, and his crew of six Senegalese men work in silence as wind whistles through the metal walls of an empty warehouse nearby. There was a time when the wharf buzzed with activity before the 7 a.m. auction, but the port hasn’t been crammed with boats in years.
The 68-year-old captain shows no emotion as the fish go in auction for a decent price. He’s the last of a long dynasty of Bermean fishermen, and all he cares about is the next catch. “I want to go out tomorrow again,” he says, marking the words with the distinct pronunciation of native Basque speakers, a language so old no one’s figured out when it originated. “I might not even go home this time. I might just take a quick nap on the boat.”
Albonigamayor doesn’t know it, but he’s crucial in the fight against climate change. Every time he goes out to sea, he brings back the lowest-carbon animal protein available anywhere. Preserved in oil and put in cans and jars in factories just a mile away, his catch of longfin tuna becomes an unsung fix for a warming planet—a meal that’s cheap, requires no energy for refrigeration, almost never spoils, and, with some effort, can be harvested sustainably.
The way we eat is a major source of the greenhouse gas emissions that are pushing global temperatures to new extremes. To address this problem, investors are funding the development of animal proteins that can be cultured in a laboratory rather than raised on a farm, while food companies are marketing (with significant difficulty to indifferent shoppers) meat substitutes made from plants. It’s all part of the drive to break the connection between the unstoppable human appetite for meat, poultry, and fish and the parallel rise in planet-warming emissions.
But sitting on the supermarket shelf, ready to eat without research and development or consumer shifts, is an almost perfectly low-carbon protein that’s existed for two centuries: tinned fish.
“Wild fish give you the highest amount of protein with the lowest carbon footprint,” says Gumersindo Feijóo, a chemical engineer at the Universidade de Santiago de Compostela in Spain’s northern region of Galicia. He’s studied the environmental and carbon impact of the tinned fish industry since the 1980s. “Put it in a can and it gets even more interesting, because it keeps the flavor and the nutritional value and it doesn’t need refrigeration or cooking.”
Tinned fish—known as conservas in Spain and Portugal, where they’ve never gone out of style—are making a comeback in foodie culture, with chefs touting the ingredient on menus and gourmet shops using the colorful retro designs on the tins to lure customers. “It has such a long shelf life that the actual food waste is almost zero,” says Henry Rich, owner of Rhodora, a wine bar in the trendy Fort Greene neighborhood of Brooklyn, that aims to send nothing to landfills. His menu is built around pickled vegetables, hard cheeses, and tinned fish, all items that minimize spoilage. “And the aluminum in the tin can be recycled and reused.”
Do the choices of chic, climate-minded restaurant goers in New York, London, or Munich matter as heat waves, floods, and fires disrupt lives on every continent? Well, yes, at least according to climate researchers. Consider that wealthy nations do the greatest environmental damage per capita—and of all lifestyle choices, changes in diet rank among those that have the highest impact in reducing carbon. That’s because the food supply chain accounts for at least 35% of human greenhouse gas globally, according to a 2020 research paper led by scientists at the University of Illinois at Urbana-Champaign. Emissions from animal-based foods are double those from plants, but the consequences of animal proteins vary widely. Reducing intake of the highest-emission sources like beef in favor of lower-carbon alternatives can have a significant effect while providing more nutritional benefits, according to new research published in Nature Reviews Earth & Environment.
Wild fish don’t need much. There’s no feed, eliminating an enormous source of emissions associated with livestock raised on grains or in pastures. There’s no energy required to grow or maintain fisheries, and sardines don’t belch methane like cattle. The small carbon footprint from eating wild fish comes mainly from the fuel burned by fishing ships.
Relative to the global impact of all agriculture and livestock production, catching wild fish represents just 4% of the overall emissions, according to a 2018 study in Nature Climate Change. And the type of fish that go into cans account for an almost nonexistent 2% share of the small emissions associated with catching wild fish.
The main obstacle to expanding consumption of canned fish is ensuring that wild fisheries remain a renewable resource, safe from depletion by overfishing. Bart van Olphen, a former chef at a Michelin-starred restaurant in Paris who left to run his own fishmonger business in his hometown of Amsterdam, learned this lesson the hard way. “One of the NGOs I was working with came to my store and made me aware of the fact that 80% of the fish I had on the counter came from a nonsustainable source,” he says. “It doesn’t make any sense if you go for a lower carbon footprint but your fish is coming from a nonsustainable source.”
At the moment, however, only 16% of the world’s wild catch is certified by the Marine Stewardship Council, the nonprofit behind the largest sustainable fishing program. The MSC combines data from scientists and fishermen to determine when a fishery is being harvested sustainably. The group safeguards against overfishing and affirms that fish are caught with methods that don’t harm the marine environment and that limit the number of animals from other species caught accidentally, such as sharks, dolphins, or turtles.
Small pelagic fish that are often sold in tins are found far from shore and in the midwater or the top layer of the oceans. They also “reproduce very quickly,” says Edouard Le Bart, MSC regional director for Southern Europe. “The only hard part is to manage the fishery. But once you’ve done that, it’s a free source of protein.”
The MSC will withdraw its label from fisheries that overstep their limits by overfishing or using techniques that harm other species. That was the case with sardine fisheries in Portugal, the Bay of Biscay, and Southern Brittany, which lost approval as stocks went down. The Cantabrian Sea anchovy also lost MSC certification and then, as fish stocks recovered, regained it a few years later.
“It’s a matter of making the most out of the fishery, but the most doesn’t mean to fish as much as possible,” Le Bart says. “It means fishing in a way that every year we can keep profiting from this resource.”
Much of the fish consumed in the world today—44% in 2020, according to a report this year from the United Nation’s Food and Agriculture Organization—is eaten fresh and therefore close to shore. An additional 35% is frozen, and just 11% is canned. “Centuries ago we didn’t have huge supply chains and refrigeration systems, so people had to look for alternatives,” says Cheila Almeida, a researcher at the Instituto Português do Mar e da Atmosfera in Lisbon.
Salt and spices were used until Napoleon Bonaparte intervened. In 1795 he offered a prize for the invention of better food preservation that would give his military a logistical advantage in campaigns to invade faraway lands. The method of boiling food and keeping it in hermetically sealed containers was so successful that cans found in 19th century shipwrecks are fit for consumption today.
Canned food remained a relatively rare product until a French ship carrying jars of fish sank off Spain’s northwestern coast of Galicia in 1840. The area is known as Costa da Morte, or Death’s Coast, with rocky cliffs and violent storms whose toll was occasionally enhanced by Galician scavengers who’d shut down lighthouses and harvest whatever washed up on shore. The same year the shipment of French jarred fish was lost at sea, a preserved fish factory opened in Galicia using the French method.
Today, Galicia remains the top-producing region of tinned fish in Spain, which is in turn the world’s second-largest producer after Thailand. Much of the fish that Albonigamayor’s and dozens of other small ships catch by pole in the Atlantic ends up in a handful of factories in the outskirts of Bermeo. The village of just over 15,000 people is home to some of the world’s main tuna fishing companies; 10% of tropical tuna globally is caught by Bermean ships. All of it is certified sustainable by the MSC.
“It wasn’t always like this,” says Ignacio Serrats, director of Conservas Serrats, pointing at the slick new offices where a very subtle scent of fresh fish floats in the air. “At the old factory there were pallets piled up on top of barrels full of salting anchovies to prevent the ceiling from collapsing.”
He’s the fourth generation at the helm of the company, founded in 1890 by an ancestor who came from a family with an anchovy preservation business in L’Escala, on Spain’s Mediterranean coast. When he took over from his father—“a tough man from Bermeo who did it all himself”—Serrats focused on modernizing processes and installations. Then it almost fell apart.
“We had been warning since 2001 that the anchovy population was falling sharply,” says María Santos, a senior researcher on sustainable fisheries management at AZTI, the scientific organization that studies Cantabrian Sea fisheries. “Then in 2005 the fishermen went to sea and found nothing.”
The estimated biomass of anchovies at sea plummeted, and authorities shut down the fishery for five years. It’s since regained its MSC certification, and data from AZTI show the stock is at the highest level on record.
To Serrats, the ban was eye-opening. “It never occurred to me that there could be no anchovies,” he says. “We had no alternative supplier, because since the times of my great-great-grandfather we had always worked with Cantabrian anchovies.”
The wilderness and lack of human intervention that make fish such as anchovies and albacore low-carbon also make them extremely vulnerable to climate change. Warming waters are pushing stocks farther north and are thought by scientists to make new generations of fish smaller. That’s why some of Spain’s tinned fish producers are pushing at the limits of eliminating emissions.
“Even if the footprint is small, the more you process, the more you increase the carbon footprint,” says Feijóo, the Galician researcher. “When you make tinned fish you have the energy needed to cook it, the oil that helps preserve it, and, of course, the tin.”
Last year, Serrats installed solar panels on the factory’s rooftop that fully power the plant during the sunniest hours. This year a new nanofiltration machine will start purifying the salty wastewater that results from boiling the fish. About 90% of that water will be fit to cook fish again and recirculated, drastically reducing water waste and costs.
Until a few months ago, nanofiltration seemed eccentric. The Basque Country is so green, lush, and rainy that its climate and landscape are often compared to those of England and Scotland. But in August a ship made headlines as it entered the port of Bermeo carrying 2 million liters of water, an exceptional measure taken for the first time to help the region deal with drought after seeing its lowest rainfall since 1859.
“We spent €300,000 [$290,000] on that machine because we wanted to reduce our water consumption and to contribute to the circular economy,” Serrats says. “I can’t believe we’ve been proven right so quickly.”
Conservas Antonio Pérez Lafuente, a company whose origins date to 1892 in the Galician village of Vilanova de Arousa, not far from where the French ship sank, has put a biologist in charge of production. The work entails calculating and lowering the companywide carbon footprint.
Conservas Antonio Pérez Lafuente sources all its fish from local fishermen—except for a kind of octopus found only along the Peruvian coast—and the oil and spices in its cans are certified pesticide-free. Most of what it produces is exported under the Pan do Mar brand to France, Germany, the UK, and the US.
Its carbon footprint has decreased every year since 2013, first by switching off a fuel-powered boiler to cook the fish in favor of natural gas, then by replacing old, leaky coolers. Now solar panels cover some of the factory’s electricity needs, with the rest sourced to a renewable power utility.
“It gets harder to lower our footprint every year because the big stuff has already been done,” says Alejandro Balufo, who studied under Feijóo at the Universidad de Santiago de Compostela and is now in charge of lowering Conservas Antonio Pérez Lafuente’s carbon footprint. “What’s left are small things, things we can’t afford or that don’t exist yet.”
Pan do Mar’s logo and nutritional information aren’t printed directly on the aluminum—which makes recycling more energy-intensive—but instead on a compostable cardboard box. A number printed in each box allows buyers to track where and when the fish was caught, by which ship, and the name of the captain commanding it. “I get 15 to 20 emails from buyers all over the world every month asking about these details,” says Balufo. “It’s our way of telling people that this stuff is important to us.”
The line-fishing methods, the sustainability certifications, and the attention to detail are all helping small tinned-fish makers like Serrats (which employs 100 people) and Conservas Antonio Pérez Lafuente (with just 40 workers) to increase the number of clients abroad and the number of countries they export to.
Back in Bermeo, Serrats pulls a glass jar from a shelf in the Conservas Serrats office and shakes it. There’s nothing special about the albacore floating in oil inside it, except that it was caught, processed, and jarred about 40 years ago. From time to time, the Serrats family gathers around an old can and opens it just to check that the contents are as tasty as the day they were made.
“We’ve started to make anniversary cans that we’ll sell in 25 and 50 years’ time, just like the wine,” he says. “It’s our way to say that we plan to be around for a while.”