Octopus Intelligence: Why Bans Are Stacking Up Worldwide

The short version. In 2026, industrial octopus farming is on its way to becoming illegal across much of the Western world. The reason fits in one sentence: science has confirmed what Greek, Japanese and Breton fishers long suspected — the octopus feels, anticipates, remembers, and suffers. The London School of Economics review (2021) reshaped British law. Washington banned octopus farming in March 2024. California passed the OCTO Act in September 2024 — the first jurisdiction in the world to ban both farming and the sale of farmed octopus. Seven other U.S. states have followed. In Spain, Nueva Pescanova's project — what was meant to be the world's first commercial octopus farm — has been suspended since the fall of 2024. Here's why this story matters, and what it says about our relationship with marine life.

A hand reaching into the ocean

If you haven't yet seen My Octopus Teacher, stop for two minutes. Craig Foster's documentary, released on Netflix in 2020 and awarded the Academy Award for Best Documentary in 2021, did something rare: it took a conversation previously confined to research labs and put it in front of tens of millions of viewers. One man, a kelp forest off South Africa, and an octopus who, day after day, accepts his presence. At the end of the film, the animal reaches a tentacle out toward him. Not to hunt. Not to defend. Just for something that looks, to all appearances, like a gesture of recognition.

The image is beautiful, but it's not the point. The point is what that scene — seen by tens of millions of people — shifted in public opinion. Five years later, the question is no longer "is the octopus intelligent?" It has become "how can we still consider farming it in industrial tanks?" And it's this second, more uncomfortable question that we'll unpack here — calmly, with the evidence.

Nine brains, three hearts, blue blood

Before any ethical consideration, there's biology. And octopus biology is, to put it mildly, foreign territory.

One central brain, eight peripheral brains

The common octopus (Octopus vulgaris) has a central brain, located between its eyes, with roughly 180 million neurons. But that brain only accounts for just over a third of its total nervous system. The remainder — about 320 million neurons — is distributed across the arms, with one ganglion per arm, each able to process information locally. The work of researchers like Laure Bonnaud-Ponticelli at France's Muséum national d'Histoire naturelle, alongside the broader cephalopod neuroscience community, has helped map this unusual nervous system in detail. Practically speaking: an octopus arm can "decide" to grasp an object without the order traveling through the central brain. The arm knows, in a sense.

For anyone used to the vertebrate model — single brain on top, body below — it's a complete reorganization of how cognition can work. Where we centralize, the octopus distributes.

Three hearts, blue blood, and a sharp memory

Three hearts: two branchial hearts that pump blood to the gills, and one systemic heart for the rest of the body. The blood itself is blue — hemocyanin, copper-based, replaces our iron-based hemoglobin. On the cognitive side, the octopus opens jars, solves mazes, recognizes individual human faces (Jennifer Mather's individual-recognition work has been replicated), uses tools (coconut shells carried as portable shelter), and shows a behavioral flexibility few other invertebrates approach.

The 2021 turning point: affective pain

For a long time, the scientific debate hinged on a single question: "does the octopus feel pain, or only show a nociceptive reflex?" The distinction matters. A reflex is mechanical. Felt pain is a subjective experience. In 2021, the study by Robyn Crook published in iScience delivered an answer that became a reference: cephalopods exhibit affective pain — pain with an emotional component, not just a motor reaction. Translated into observable behavior: an animal that learns to avoid a place where it suffered, that durably modifies its behavior, that shows signs of prolonged stress. Not a biological thermostat. A being that remembers having been hurt.

Animal sentience: the ethical and legal turning point

This is where science meets law.

The LSE 2021 report — Birch and colleagues

In November 2021, the UK Department for Environment, Food and Rural Affairs commissioned the London School of Economics to conduct an independent review of the scientific literature on the sentience of cephalopods and decapods. Jonathan Birch's team, professor of philosophy of science, reviewed more than 300 studies. The verdict: the evidence is sufficient. Cephalopods (octopuses, squid, cuttlefish) must be considered sentient beings, capable of subjective mental states — including pain, pleasure, and fear.

UK Animal Welfare (Sentience) Act 2022

Within weeks, the UK Parliament passed the Animal Welfare (Sentience) Act 2022. The text legally recognizes the sentience of cephalopods and decapods — a first in Western Europe. In practice: any future UK policy decision must now factor in the welfare of these animals.

The European paradox

At the EU level, the situation is more ambiguous. Directive 2010/63/EU protects cephalopods used for scientific purposes. But it doesn't cover those destined for food or aquaculture. In other words: in the lab, the octopus has rights. In an aquaculture pen, it doesn't. That legal vacuum is precisely what allowed Nueva Pescanova to move forward — and what's now being contested.

Bans stack up: a 2021-2026 timeline

In five years, the legal landscape has transformed. Here's the trajectory.

November 2021 — The Birch / LSE report is published. Scientific recognition of cephalopod sentience.

April 2022 — The UK passes the Animal Welfare (Sentience) Act.

March 2024 — Washington State enacts HB 1153, the first state-level ban on octopus farming for human consumption in the United States.

July 2024 — In Congress, Senators Sheldon Whitehouse (D-RI) and Lisa Murkowski (R-AK) introduce the Opposing the Cultivation and Trade of Octopus Produced through Unethical Strategies (OCTOPUS) Act. A bipartisan text — rare these days — that would ban commercial octopus farming on federal soil and prohibit the import of farmed octopus.

September 2024 — California enacts the OCTO Act (AB 3162), sponsored by Assembly Member Steve Bennett. California becomes the first jurisdiction in the world to ban both the farming and the commercial sale of farmed octopus.

October 2024 — The Canary Islands government, following an unfavorable environmental impact assessment from Spain's Ministry of Ecological Transition, suspends Nueva Pescanova's industrial farm project in Las Palmas de Gran Canaria.

2024-2025 — Connecticut, Hawaii, Massachusetts, New Jersey, New York, North Carolina and Oregon all introduce or advance their own octopus-farming bans. The Eurogroup for Animals publishes a March 2025 position paper urging the European Commission to ban cephalopod farming Union-wide.

2026 — Several additional U.S. states are reviewing equivalent legislation. The debate is now open in multiple European regional parliaments.

In five years, we've moved from "we don't quite know yet" to "the science has spoken, now we draw the consequences." The speed of that shift, in the world of public policy, is unusual. It says something.

Nueva Pescanova: the silent collapse

The Nueva Pescanova case deserves its own pause, because it concentrates the entire debate in a single file.

The Galician company, headquartered in Vigo, announced in 2019 its intention to open the world's first industrial octopus farm in Las Palmas de Gran Canaria. Announced investment: €65 million (roughly $70M USD). Planned capacity: one million octopuses per year. The slaughter method described in the technical documents submitted to the Canarian authorities: immersion in ice baths at -3 °C (27 °F). A method that the scientific community flagged, from the moment the plans were published, as slow and stressful for a neurologically complex animal.

The second problem, less visible but structurally just as heavy: the octopus is a strict carnivore. Producing one kilogram of farmed octopus requires roughly three kilograms of wild fish (sardines, mackerel, anchovies) caught at sea. In other words, an octopus farm doesn't grow the food supply — it accelerates overfishing by converting already-scarce marine protein into a more prestigious end product. Compassion in World Farming and the Aquatic Life Institute have documented this ratio in detail.

In 2024, after the unfavorable environmental impact ruling, the Canarian government suspended the authorization. As of May 2026, the project remains on hold. Several investors have stepped away. What was supposed to be the blueprint for a new global supply chain is, for now, a stalled file.

The octopus: first "domino animal"?

That's what's happening. And here's what strikes me most about this story.

The octopus is becoming what some ethicists now call a "domino animal" — a case whose moral resolution, because it's too obvious to contest, knocks down other dominoes behind it. If we accept that the octopus shouldn't be farmed in tanks because it feels, remembers, and suffers, what does that say, in mirror image, about the chicken in a confined barn, the salmon in a sea cage, the pig in a closed building? Nothing — for now. But the question is being asked, precisely because the octopus case is too clear to ignore.

That's exactly what worries defenders of industrial farming — and exactly what's fueling the mobilization. Peter Singer was already writing in the 1970s about speciesism: the tendency to grant different moral consideration to living beings based on species alone, without rational justification. Forty years later, that framing is back at the front of the conversation.

Literature has also taken up the subject. Remarkably Bright Creatures by Shelby Van Pelt, published in 2022, tells the story of an unlikely friendship between an elderly widow and an aquarium octopus — a New York Times bestseller, adapted for Netflix in 2026 starring Sally Field with Alfred Molina as the voice of Marcellus. And further back, naturalist Sy Montgomery's The Soul of an Octopus (2015) — a National Book Award finalist — was one of the first popular-science works to bring the cephalopod inner life into the mainstream. These books are not editorial coincidences — they answer a real cultural demand.

What I take from all this: the conversation has shifted. And it's no longer possible, in 2026, to talk about the octopus the way we talked about a shrimp twenty years ago.

The seaweed path

None of this, of course, says anything about what goes on the plate instead — that's another conversation.

For my part, for thirty years I've been working on one complementary answer — not the only one, not the unique one: edible seaweed. Japan, Korea, Brittany, Galicia — entire cultures have built their relationship to the sea without depending solely on harvesting complex species. Dulse, wakame, nori, kombu, sea lettuce: these marine vegetables offer a dense nutritional profile (minerals, protein, phytonutrients) with an ecological footprint nothing like industrial fishing.

With Aurélie, I spent several years documenting this path in Algues au Quotidien (Gallimard, 2024), which received the Gourmand World Cookbook Award 2025 and the Académie Nationale de Cuisine 2025 prize in the seafood category. It's not an activist book — it's a cookbook. But it's our way of saying that the alternatives exist, and they're already within reach of a fork.

To go deeper on edible seaweed: the seaweed category at Biovie.

FAQ — Octopus intelligence

Is an octopus as smart as a 5-year-old?

Direct comparisons with human developmental stages are tricky — octopus and human cognition evolved on completely separate paths for over 500 million years. That said: octopuses demonstrate behaviors that overlap with capacities scientists associate with toddler-to-preschool-age human cognition in specific domains. They solve novel problems (opening child-proof jars), use tools (carrying coconut shells as portable shelter), recognize individual humans, and learn by observation. The most accurate framing isn't "as smart as" — it's "intelligent in a parallel, non-vertebrate way."

How many brains does an octopus have?

One central brain plus eight peripheral ganglia — one per arm. That's what scientists call a distributed nervous system. The central brain holds about 180 million neurons; each arm holds about 40 million. Total: roughly 500 million neurons. The popular phrase "nine brains" is a simplification, but it captures the functional reality: an octopus arm can act before the central brain has issued an order.

Do octopuses have a high IQ?

The IQ concept, designed to measure human cognition, doesn't transfer cleanly to other species. But on the cognitive functions we associate with intelligence — learning, memory, problem-solving, behavioral flexibility, individual recognition — octopuses score remarkably well. They learn by watching, recognize individual keepers, show preferences (some aquarium octopuses "aim" jets of water at visitors they don't like), and adapt quickly to new environments. The Crook (iScience 2021) and Birch (LSE 2021) papers add a further layer: octopuses don't just react — they feel.

Can octopuses feel affection toward humans?

Whether what we observe is "affection" in the human sense remains debated. What is documented is consistent individual recognition (an octopus behaves differently toward a familiar keeper vs. a stranger), repeated voluntary contact-seeking, and what Craig Foster's My Octopus Teacher popularized: sustained gestures of approach that don't fit a feeding-or-defense explanation. Scientists tend to call this interspecies curiosity rather than affection — but the boundary is genuinely thin.

What is the #1 smartest animal in the world?

The ranking depends on the criteria. Great apes (chimpanzees, bonobos, orangutans), cetaceans (dolphins, orcas) and corvids (ravens, crows, magpies) consistently top the list among vertebrates. Cephalopods — octopuses, cuttlefish, squid — are today regarded as the only invertebrate group reaching a comparable level of cognitive complexity. The octopus stands out for having developed that intelligence on a completely independent evolutionary line, separated from vertebrates for more than 500 million years.

Why is octopus farming being banned?

Three cumulative reasons. First: science has confirmed that the octopus experiences pain affectively, not just reflexively (Crook 2021, Birch LSE 2021). Second: no industrial slaughter method has been validated as humane for this species; the protocols proposed (ice baths at -3 °C) are considered slow and stressful. Third: the octopus is a strict carnivore — producing one kilogram of farmed octopus requires roughly three kilograms of wild fish, which amplifies pressure on already-overfished marine ecosystems. These three reasons drove the UK, California (first to ban farming and sale), Oregon, Washington and seven additional U.S. states to legislate, and Spain to suspend the Nueva Pescanova project.

Scientific and institutional sources

1. Birch J. et al. (2021). Review of the Evidence of Sentience in Cephalopod Molluscs and Decapod Crustaceans. London School of Economics, commissioned by Defra (UK).
2. Crook R.J. (2021). Behavioral and neurophysiological evidence suggests affective pain experience in octopus. iScience, 24(3).
3. UK Parliament (2022). Animal Welfare (Sentience) Act 2022.
4. California State Legislature (2024). Assembly Bill 3162 — OCTO Act.
5. Compassion in World Farming. Octopus Farming: A Recipe for Disaster.
6. Aquatic Life Institute. Octopus Farming Resources.
7. Montgomery S. (2015). The Soul of an Octopus. Atria Books. National Book Award finalist.
8. Van Pelt S. (2022). Remarkably Bright Creatures. Ecco Press. New York Times bestseller.

Last updated: May 2026. Article written by Éric Viard, founder of Biovie (since 2007) and tropical agricultural engineer (ISTOM). Co-author with Aurélie of Algues au Quotidien (Gallimard / Alternatives, 2024), Gourmand World Cookbook Award 2025 and Académie Nationale de Cuisine 2025 prize (seafood category).

Disclaimer. The information in this article is provided for informational purposes and reflects the state of scientific and legal knowledge as of May 2026. It does not constitute veterinary advice, legal advice, or a consumption recommendation. For any dietary question, consult a qualified professional.