[Animals] Op-Ed | Aquaculture Is Expanding Fast. Our Understanding of the Animals in These Farms Isn’t

[protaa]

 

 

In late May, the Royal Society for the Protection of Cruelty to Animals CA suspended a Scottish farm from its animal welfare certification scheme after an environmental group released footage of alleged animal cruelty. The video shows workers leaving salmon out of water, crushing a fish’s head, and beating several fishes. Major retailers halted purchases of salmon from the farm while investigations are underway.

This sort of treatment violates most people’s expectations for humane handling of farmed animals, including fish. Recent surveys show that an overwhelming share of residents in the United Kingdom, nine countries across the European Union, and the United States believe that farmed fishes should have strong welfare protections and want to buy fishes raised humanely.

The stakes of meeting society’s expectations are high—on multiple fronts.

Aquaculture raises a staggering number of individual animals for human consumption. Unlike farmed land animals, production of farmed aquatic animals is reported in tonnage, i.e., weight of the animals, rather than in number of individuals. Based on tonnage reported by the U.N. Food and Agriculture Organization (FAO), recent estimates suggest that the world farmed between 250 and 408 billion individuals—including 59 to 129 billion vertebrates, like fishes—in 2018. By comparison, the world slaughtered 78 billion land animals that same year.

In addition, the individuals raised in aquaculture represent a wide range of species that, in most cases, humans have only recently started to farm. According to the FAO, 530 animal species have been produced in aquaculture since 1950 as of 2022, spanning fishes, mollusks, crustaceans, marine invertebrates, frogs, and turtles. Industry brought most of these animals under human control only in the last few decades, an exponential rate of attempted domestication. In contrast, the roughly 20 species in terrestrial animal agriculture were domesticated thousands of years ago.

Also, attempting to farm so many species so quickly has come at a high cost to the animals. Every species has unique and specialized welfare needs—specific conditions required for their biological, behavioral, and emotional well-being. Moreover, certain traits, like having involved parental care or courtship rituals, are particularly difficult to satisfy in farming systems. Recent work has shown that approximately one-third of the species in aquaculture have traits that place them at high welfare risk.

Among these species are the red swamp crayfishes, who care for their young for a three to four months and actively search for them if separated, and the bumphead parrotfishes, who live for up to 40 years and gather in the hundreds under the full moon to spawn. It’s easy to see how restrictive farming systems, optimized for production, are inherently at odds with these animals’ basic needs and well-being.

Exacerbating these welfare risks is the dearth of specific information about aquacultured animals’ welfare needs. Humans have had thousands of years to develop understanding of farmed land animals’ basic needs, but mere decades—or less—to do so with most aquatic species. A 2021 assessment of the scientific welfare literature for farmed aquatic animals revealed that species-specific information was available for only 84 species, about one-third of individuals farmed. For 231 farmed species—128-183 billion animals, nearly half of those raised in aquaculture—there were no welfare publications at all. This isn’t an animal welfare knowledge gap. It’s a Grand Canyon.

Even when welfare harms are documented, they are seldom recognized as harms in the scientific literature. In a recent paper, we identified four types of harms driven by aquaculture, collectively termed “dewilding”: environmental degradation, harms to wildlife, captivity effects, and changes in humans’ perceptions of the nonhuman world. Across nearly 800 scientific papers documenting dewilding, harms to captive animals were most frequently documented. Yet they were also rarely acknowledged as harms. Some studies, for example, described disease prevalence on farms and infection characteristics—without noting their associated welfare impacts. This finding signals a deeper issue. It’s not just that aquaculture raises many species with welfare risks and without welfare information; the scientific literature and attendant discourse can fail to recognize animal suffering even when it’s visible.

Aquaculture also changes the animals themselves. Animals like Atlantic salmon are selectively bred to maximize production, e.g. to grow larger and faster. One company even tried to genetically engineer salmon to achieve these goals. But those aren’t the only changes occurring. Animals adapt to their captive environments, and these changes can occur in just a few generations. Salmon farmers don’t necessarily want fishes to behave more aggressively than their wild counterparts, but crowded farms and predictable food set the stage for more aggressive fishes to eat more and be more successful. Both intentionally and inadvertently, aquaculture shapes animals to become optimized units of production, reflecting an increasingly human-centric world.

Humanity certainly needs strategies to feed a growing global po[CENSORED]tion. Aquatic foods can offer numerous benefits, including food security, nutrition, employment, and environmental health. As we build this food system, however, we need to scrutinize the true value of those benefits—are certain aquaculture sectors, for example, exacerbating malnutrition in countries from which they source fish feed?—and weigh them against the expense to other animals. Before we stumble into creating systemic welfare harms and more incidents of animal cruelty, we can and should ask: how can we farm with an eye toward minimizing or altogether avoiding welfare harms?

Building a sustainable, nutritious food system while minimizing risks to other animals isn’t a pipe dream. Aquatic plants like seaweed, which entail no farmed animal welfare risk, offer one possible nutritious, low-cost, and environmentally sustainable path. The decisions we make now about aquaculture will shape the future of our food system, planet, and our relationship with other animals. Will we make the right choice, for us and for them?

 

https://foodtank.com/news/2025/09/op-ed-aquaculture-is-expanding-fast-our-understanding-of-the-animals-in-these-farms-isnt/