The science of animal feed—combining corn, soy, grain, and other ingredients like fishmeal to raise livestock faster, more efficiently, and at a larger scale—was central to the rise of modern civilization.¹⁹ Techniques of animal husbandry developed roughly 12,000 years ago in the so-called “Fertile Crescent,” an ancient area stretching from Mesopotamia to Egypt.²⁰ Alongside advancements like irrigation and the plough, the domestication of livestock was essential for humans to create the stable food supply that they needed to settle and eventually to develop cities.²¹ Shifting from grazing to penning animals required farmers to provide them with balanced diets.²²

Historically, marine life itself has experienced a conceptual shift. First, these creatures were animals that served mostly as sustenance for seabirds, marine mammals, and larger predatory fish, and, on a local scale, as food for humans. Next, they were seafood to be eaten by humans on an industrial and global scale. Then, with the rise of the reduction industry, marine creatures emerged as an ingredient in the form of flour, oil, or protein, destined as livestock feed.²³ Ocean habitats became calorie factories.

Kristin A. Wintersteen explains how and when the modern world began using the sea as a protein mine.²⁴ In her 2021 book, The Fishmeal Revolution, she chronicles how the Humboldt Current, a cold, nutrient-rich upwelling system that runs along the Pacific coast of South America, was reconceptualized from being a living marine ecosystem into a place to extract raw materials. This “revolution,” she explained, converted Peru into the fishmeal superpower it is today, now accounting for roughly a quarter of global production. This historical transformation made fishmeal the key ingredient that helped fuel the post-World War II expansion of industrial chicken, hog, and later fish farming—especially in the US and northern Europe. This shift, which has since extended far beyond the waters of Peru to include the coastline of West Africa, has also severed consumers from the ecological and human costs of production.²⁵

Fishmeal and its rise as a staple feedstock have come with a variety of hidden costs that rarely show up on the balance sheets of the seafood companies that rely on it. These hidden costs, or what economists call “externalities,” are instead paid by people who are far from where the seafood gets eaten.²⁶ “You can’t start your sustainability assessment of aquaculture at the fish farm,” said Beth Lowell, Oceana’s vice president for the US, “You have to look further up the supply chain and account for the fish that are being ground into feed.”

The oceans also pay an especially heavy and unseen toll from this industry. More than a fifth of all marine life pulled out of the water globally was swallowed up by the feed industry in 2022, according to the UN’s Food and Agriculture Organization (FAO).²⁷ Reduction fishing often relies on purse-seine or trawl nets that can trap large amounts of non-target fish, or bycatch, significantly impacting the ecosystem by removing key prey species.²⁸ As such, the reduction industry represents a stark example of “fishing down the food web,” where fishing shifts toward smaller, less valuable species as larger, predatory fish stocks decline. The true cost of farmed fish is not what appears on the restaurant menu or the grocery store packaging.

Most fishmeal is used by the aquaculture industry. This is ironic since, historically, the global push toward aquaculture has been bolstered by the idea that farming fish on land lessens the need to take so many from the sea. Using fishmeal to feed fish farms, however, has turned this goal upside down, and fish farming is accelerating ocean depletion. The toughest challenge to farming carnivorous fish is feeding them. Food constitutes roughly 70 percent of this industry’s overhead, and so far, the only commercially viable form is fishmeal.²⁹ The aquaculture farms that yield some of the most popular seafood, such as salmon, tuna, shrimp, carp, or European sea bass, often consume more fish than they ship to supermarkets and restaurants.³⁰ Before it gets to market, a farm-raised tuna, for example, can eat more than 15 times its weight in free-roaming fish that has been converted into fishmeal.^31M

Aquaculture has existed in rudimentary forms for centuries before it became industrialized on a large scale in the 1980s, and it has some clear benefits. Fish farming provides millions of people with year-round access to affordable protein.³² In India, aquaculture is a crucial source of jobs, especially for women.³³ In Bangladesh, fish farming has driven an overall decline in the price of fish, making it more accessible for lower-income households.³⁴ Even when feed—including ingredients like soy and fishmeal—and transport to the US are taken into account, some types of fish farming, such as tilapia and Atlantic salmon aquaculture, have lower greenhouse gas emissions per pound compared to beef and pork.³⁵ Farming bivalves, including clams, oysters, scallops, and mussels, is particularly sustainable: These species typically require no feed and use minimal land and freshwater.³⁶ They also produce shells that can function as a form of carbon capture, according to a 2020 Nature Food study.³⁷ As of 2022, roughly a third of global aquaculture did not require external feed inputs.³⁸

As the planet’s population has grown, so too has competition for key nutrients. Countries are struggling to reduce their reliance on imported meat in a bid toward “protein sovereignty.”³⁹ Investors are chasing alternative protein sources like plant-based or lab-cultivated meat. Disruptions such as the avian flu and the Russia-Ukraine War have led to sharp jumps in meat prices, casting new focus on the interconnectedness and volatility of these commodity markets. “With increasing frequency, wealthy, food-importing countries and private investors are acquiring farmland overseas,” said a report from the Wilson International Center titled “Land Grab? The Race for the World’s Farmland,” explaining that many of these purchases are for the sake of growing more food.⁴⁰

In the context of this global fight for prized resources, feed represents a hidden battle behind the broader war. Competition is especially fierce for crops, particularly soy, that are fed to livestock. “China, the US, and Brazil are the world’s three largest producers of meat by far, and they all rely on and are bound together by one commodity: the soybean,” said a 2024 podcast by Carnegie Endowment for International Peace.⁴¹ “In 2024, US-China trade tensions are mostly centered on high-tech products like semiconductors or critical minerals. But in 2018, one of the first battlegrounds for these superpowers was the soybean.”⁴² As with soy, the scramble for fishmeal and fish oil is fueled by the same geopolitical desires for sovereignty and control over vital resources. And yet, this contest is happening not on land but at sea, where there is far less focus from journalists, governments, and environmental or human rights advocates.⁴³

The fishmeal industry and aquaculture industries have made a variety of arguments about their sustainability. For example, the IFFO, which is the international fishmeal association, has emphasized that its “role is not to advise which markets should use fishmeal and fish oil.”⁵⁷ Véronique Jamin, a spokesperson from the organization, said that fish farming is “the most efficient animal protein system” and “is becoming more efficient over time, not less: lower inclusion rates of fishmeal/oil, higher digestibility of alternative ingredients, better feed formulation through precision nutrition.”⁵⁸ She added that “sustainability frameworks won’t work if they ignore real-world economics,” and seafood companies have to respond to “what people actually want to buy and eat.”⁵⁹

Ocean researchers and marine historians, however, offer a different view about global demand for fishmeal and farmed fish.⁶⁰ First, they contend that it was the aquaculture industry itself that is driving increased demand for farmed fish. "Classic market economics explains that making a resource cheaper and more efficient does not curb its use; it increases it," said a 2026 report by the Aquaculture Accountability Project. "Instead of meeting a preexisting need, confining hundreds of thousands or millions of fish in net pens to produce cheap seafood has created what economists call ‘supply-driven demand.’”⁶¹ A 2024 study by Science Advances furthered this point: Aquaculture companies have “driven an increase in demand for salmon, rather than having simply met a pre-existing demand.” The research concluded that the aquaculture industry has exponentially increased the supply of affordable “premium” fish like salmon, leading to higher demand, the opposite of its claim to be meeting an existing need.⁶²

In defense of its sustainability, the feed industry has also emphasized that it is decreasing its reliance on fishmeal and fish oil, and especially on the use of whole fish or fish that can be eaten by people. Over 58 percent of fishmeal and fish oil globally comes from whole fish in 2026, according to international fishmeal association data. At least 90 percent of the fresh fish turned into fishmeal and fish oil is food-grade, edible to humans, according to a 2017 study published in the Fish and Fisheries journal.⁶³ The IFFO has said on its website that between 2000 and 2020, the proportion of fishmeal in aquaculture feed at fish farms globally decreased from 23 percent to eight percent.⁶⁴ Some experts have predicted, however, that the total amount of global fishmeal production could rise by nearly 10 percent between 2022 and 2032, mostly from trimmings—fish offcuts not suitable for human consumption—according to the FAO.⁶⁵ Overall demand for fishmeal also seems to be increasing.⁶⁶ Five of the world’s largest salmon companies, for instance, increased their absolute use of fishmeal and fish oil made from whole wild fish by as much as 39 percent between 2020 and 2024, according to a report from the Farm Animal Investment Risk and Return Initiative.⁶⁷

Fish In:Fish Out

It can take more than 730 wild-caught Peruvian anchoveta to grow a single farmed salmon.

Wild anchoveta needed per farmed animal^MEvery mark is one anchoveta, at one size

730anchoveta 1 Salmon

390anchoveta 1 Trout

3anchoveta 1 Carp

1anchoveta 1 Shrimp

Meanwhile, global fishmeal supplies could be tapped out as soon as 2028, according to Novel Sharma, a Rabobank analyst specializing in seafood and aquaculture.⁶⁸ “A shortage is inevitable,” the report said.⁶⁹ This means that the industry’s claims about the supply, demand, and sustainability of fishmeal require broader context. While individual sectors or companies may be decreasing their use of fishmeal, the overall industry is not likely decreasing at a rate that makes it sustainable. The industry’s claims, then, resemble someone walking north on a southbound train: Individual actors may be moving in the right direction, but not nearly fast enough to change the outcome.

Assessing the climate impact of carnivorous fish farming is also complicated.⁷⁰ The industry markets aquaculture seafood as a climate-friendly protein source.⁷¹ However, its true carbon cost is sometimes obscured by selective accounting, particularly the omission of fishmeal production, which accounts for at least half of industry emissions.⁷² Comparing the climate impact of food per pound can also make farmed fish appear artificially more efficient, but one pound of water-dense cod provides only a third of the calories of one pound of pork, distorting the reality of consumption.⁷³ Meanwhile, over 165 million metric tons of CO2—equivalent to the annual emissions from all passenger cars in the UK—have been released into the atmosphere as mangroves and seagrass beds have been destroyed to make way for the global expansion of coastal fish farms, further undermining long-term carbon storage.⁷⁴ When emissions from fishmeal, habitat loss, and global supply chains are accounted for, catfish and other intensive aquaculture products can rival or exceed poultry and pork in total climate impact, according to a 2018 Science study.⁷⁵

Bill McKibben, a climate-change expert and author of Here Comes the Sun, said that hope is not lost, especially looking at promising trends tied to even some of the most intransigent global systems like fossil fuels.⁷⁶ Between 2022 and 2024, the world nearly doubled its solar power capacity from two to three terawatts, and it was on track to increase by another three terawatts by the end of 2026. As of 2025, solar was growing faster than any other power source in history. The shift was largely driven by developments in the 2020s that enabled solar power, for the first time, to become cheaper than fossil fuels. China, Pakistan, and several countries across Africa led the charge to divest from distant supplies of oil and natural gas and take up local supplies of sun and wind.⁷⁷ “If it can happen with energy, it can happen with food,” McKibben explained, adding that a relocalization of aquaculture, which pushes toward sustainable species like mollusks and away from those that rely on feed sources like fishmeal, is possible if international demand for things like salmon or shrimp decreases.⁷⁸

Though there are efforts to police food safety, oversight of feed is minimal, through certification programs or otherwise. Food writer Michael Pollan said that aside from climate-change and sustainability concerns, there are also intense food-safety problems buried within feed. “We are what we eat, but that’s only part of the story,” he said. “We are what what we eat eats, too.” This was the case with beef, which, until mad cow disease, was routinely fed to other cows. Fertilizer, chicken feces, and cow blood are still fed to cattle. “I’m imagining we know even less about what goes into fish feed than we do about cattle feed,” Pollan said.⁹²

Sara Lewis, director of programs for FishWise, a sustainability and labor non-profit organization, said that certification programs focused on aquaculture emerged after those focused on wild-caught fish, which partially explains one of their biggest flaws. “Though the intentions were to model aquaculture certifications on the wild certifications of a decade before, aquaculture has the tricky problem of needing to account for feed origins that wild fishery certifications don’t,” she said.⁹³

Five certification programs are most popular in relation to aquaculture seafood. They include Best Aquaculture Practices (BAP) and Aquaculture Stewardship Council (ASC), which concentrate on the sustainability and legality of fish farming; MarinTrust, which focuses on the processing and traceability of fishmeal and fish oil; and Friend of the Sea, which certifies both fisheries and fishmeal and fish oil processors. Countries also rely on Fishery Improvement Projects (FIPs), which aim to better the management of participating fisheries.^M But critics say that these programs can end up serving as sustainability smokescreens, as their purview is not broad enough, leaving ethics practices farther down the supply chain to fall through the cracks.^94M

Improvement?

Some ocean conservationists and labor groups have called for seafood companies and grocery chains to stop sourcing from companies or regions tied to labor, food safety, or sustainability concerns.⁹⁵ Spokespeople from several certification programs disagreed with this perspective, arguing that a carrot-rather-than-stick approach is best for improving the industry. For example, Dave Martin, a spokesperson for the Sustainable Fisheries Partnership, which founded Fisheries Improvement Projects, said, “We ask our partners and those we work with around the world to stay and help fix the problems.” He added, “Fisheries in FIPs are by definition unsustainable,” which is why they are in the program.

Asked by The Outlaw Ocean Project why, according to his organization’s own assessment, half of the fisheries reviewed had in recent years dropped into a “poorly managed” category, Martin cited two studies showing that fishery improvement projects help. He also pointed to factors that improvement programs cannot control, such as the performance of government regulators. In regions where governments have rolled back regulations and cut spending toward counting fish and enforcing quotas, Martin said his organization pushes for companies to play a larger role in preventing overfishing.⁹⁶

Certification programs for farmed seafood take a partial look at the seafood supply chain, with minimal effort to directly investigate feed sources. Importers, exporters, and retailers have motivation to apply for certifications because they allow them to raise their prices, lessen legal risk, and attract investment.⁹⁷ Further, companies have a financial incentive to believe the reassurances passed along by certifications and associates up the chain. The boat captains, fishery officials, fishmeal plant operators, feed mills, fish farmers, seafood brands, restaurateurs, grocers, and even the insurers, banks, and certifiers make up an industry full of stakeholders who receive and hand down the reassurances that sustainability and other rules are being followed. Quite often, a compounding confidence snowballs from certifications to marketing claims. Based on their certifications, seafood sellers advertise themselves as more ethical than their competitors.^M

Responsibility

In response to questions from The Outlaw Ocean Project, the various organizations that make up the certification industry emphasized that each plays its own role and cannot be held accountable for others’ responsibilities.⁹⁸

MarinTrust, for instance, emphasized that its program is not meant to be the “lone driver” but a “credible partner” to governments and NGOs. Regarding labor abuse, spokesperson Libby Woodhatch said MarinTrust’s purpose is strictly to check whether factories comply with national regulations and UN labor conventions.⁹⁹

ASC spokesperson Gaynyr Dickson added that “certification alone cannot resolve all issues related to the industry” and that it does not police labor standards directly. Instead, it relies on fish farms to get their feed from mills that have themselves been certified by other organizations. When asked if the program checks for sustainability problems with feed mills and their fishmeal producers, Dickson said they put that responsibility on the feed mills to do their own “due diligence.”¹⁰⁰

Paolo Bray, the founder of Friend of the Sea, similarly stated that his organization does not directly audit ships for labor concerns but relies on independent auditing firms that are supposed to talk to workers in port and review CCTV footage.¹⁰¹

The Global Seafood Alliance, which runs the BAP program, wrote that it is the industry’s “most comprehensive program for farmed seafood” but is also “removed from the auditing and certification decision process,” which is executed instead by third-party auditors.¹⁰²

Division of labor exists in every industry, but a 2025 report from Western Sahara Resource Watch summed up the problem it creates within the certification industry. “The business model is simple,” the report said, adding that exporters pay for certificates, certification bodies issue them, and standard owners license them. But when things go awry, the report indicated, auditors blame standards, standards blame auditors, both depend financially on the companies they are supposed to control, and almost no one answers questions. “Everyone gets paid, and when problems emerge, everyone points elsewhere.”¹⁰³

Long Chains

The further the distance between a producer and a consumer, the longer the supply chain and the less likely anyone along the way is going to look very hard at early-stage and far-away problems tied to their suppliers. With so many steps before seafood reaches a consumer, there are countless hidden places in the supply chain where criminality can occur. “Without the chain of custody, standards are not able to provide an assurance to organisational buyers and consumers that the fish they are buying was caught in the socially responsible way they are purporting,” found a 2022 study by the University of Nottingham.^104M Most grocers who sell seafood are in the dark as well. Partly, that’s because tracking seafood is unusually difficult and costly. The other reason may be plausible deniability. Companies can escape blame or the need to fix problems if they are unaware of them.

Seafood companies may face increasing legal challenges to problems within their supply chains. Historically, such companies have, intentionally or unintentionally, distanced themselves from the behaviors of their subcontractors and suppliers abroad, thereby avoiding culpability for the role of bad actors. A case brought in March 2025 by four Indonesian fishers against the canned-tuna giant Bumble Bee concerning the use of forced labor on fishing ships tied to the company could pierce that veil of plausible deniability.¹⁰⁵ The fishers sued the company in the Southern District of California for violating the Trafficking Victims Protection Act (TVPRA). The company argued in court documents that it was not responsible for the actions of the relevant fishing ships. In a landmark ruling, the district court allowed the lawsuit to move forward, finding that Bumble Bee “likely had ‘notice about the prevalence’ of forced labor on the vessels from which it sourced tuna, ‘failed to take adequate steps to train staff in order to prevent its occurrence,’” had an “active role in obtaining albacore tuna from the vessels on which Plaintiffs were subject to forced labor,” and resold such procured tuna for profit. Bumble Bee did not respond to a request for comment.¹⁰⁶