Contra Shrimp Welfare.
It is likely that installing a shrimp stunner reduces global suffering as much as making the carts in a single Walmart less squeaky for 20 minutes a year. Or perhaps not at all.
Open Philanthropy has handed $2 million to the Shrimp Welfare Project (SWP), primarily to promote electrical stunning devices, and fund staff to push policy changes. Each stunner costs $70,000 to purchase and $50,000 to distribute. The goal? To “reduce suffering” when 500 million shrimp are harvested annually by cutting their death time from 20 minutes in ice slurry to 30 seconds via electrical stunning.
This initiative may sound odd at first glance but the SWP has produced numerous blog posts, elaborate spreadsheets, and lengthy PDFs to justify their approach. They have clearly thought this through extensively, and I will look to provide a short, but equivalently thorough rebuttal.
They claim that the shrimp stunner renders shrimp “unconscious” by synchronously depolarizing their neurons with an electrical current over three seconds and then kills them around 27 seconds later. This replaces the cheaper and more common process of immersing shrimp in an ice slurry which leads to immobilisation in around a minute and death in about 20 minutes.
Promoting this stunner based approach implies that the people behind the SWP believe that disrupting neuronal firing stops suffering, a physicalist perspective that I agree with.
My disagreement, however, is with the methodology, and the assumptions that the SWP depend on to justify their conclusions; namely behavioural tests, and loose biological analogues to justify shrimp consciousness and suffering.
Neuroscience offers several frameworks for understanding consciousness:
First, it should be mentioned that shrimp have ≈100,000 neurons. Humans have ≈86 billion neurons, and only 10% of the human brain is likely to be involved in any sort of conscious calculation. Neuronal firing and interaction alone does not imply the existence of consciousness or awareness.
Global Workspace Theory states that consciousness arises when information is globally broadcast across distributed brain systems humans achieve this via coordinated fronto-parietal networks, as shown in EEG, fMRI, and MEG studies on consciously available stimuli in the human brain, but shrimp lack anything comparable; no cortex, no long range networks, no unified communication hub.
Electric Field Theories emphasize stable macroscopic fields that bind cognition. Humans generate such fields across large, integrated networks, but shrimp nervous systems are small, modular, and discontinuous, making coherent fields that integrate information very unlikely.
Marker’s midbrain theory of consciousness would imply that all vertebrates are conscious, and create a cohesive evolutionary pathway for consciousness that excludes shrimp. These theories locate consciousness in vertebrate midbrain integration hubs like the superior colliculus and periaqueductal gray. Shrimp have no clearly analogous structure, so they likely lack spatially unified representations.
Integrated Information Theory gives shrimp their strongest case for awareness: they integrate information locally, yet their overall Φ is likely tiny given sparse neurons and limited connectivity.
Based on these thresholds, P(shrimp consciousness) is very low.
Now let’s discuss P(shrimp suffering).
If we grant shrimp the minuscule amount of awareness that IIT would give them, then we must gauge their ability to suffer. It takes some skill to suffer.
Under most neuroscientific theories, suffering is not just about detecting damaging stimuli, but requires integrating multiple streams of information into a unified evaluative model that links sensation, memory, affect and motivation. The scientific consensus is that suffering evolved as an adaptive feature to motivate avoidance of harm. Some argue that consciousness evolved to create a self-model that tracks current bodily states, stores and retrieves past experiences and projects future scenarios to guide avoidance behaviours.
There is no evidence that shrimp are capable of any of those mechanisms, and despite the SWP’s unsubstantiated claim that shrimp can undergo associative learning (https://www.shrimpwelfareproject.org/are-shrimps-sentient), which most likely comes from research on crabs (not shrimp), I found no such evidence myself.
Shrimp can detect noxious stimuli, and have been observed to groom damaged antennae. There is even evidence of reduced grooming after opioid administration implying the existence of damage detection, which LSE saw as enough evidence to claim sentience. This is clear evidence that shrimp can detect damage to their bodies. That does not mean they suffer.
You, as a human, associate injury with negative valence. That does not mean shrimp do.
Your suffering scales with Anterior Cingulate Cortex (ACC) activation, not with increased activation of pain receptors. Most vertebrates have ACC analogues, but shrimp don’t. Human suffering is largely caused by ACC activation, where electrical stimulation of the region generates a reported sense of “existential distress” and lesions to the ACC allow humans to detect pain without suffering. Shrimp certainly can’t suffer in any way that we can relate to.
You can make the argument that shrimp developed the ability to suffer independently. Under this assumption, consciousness and suffering evolved along the malacostran lineage hundreds of millions of years ago in the Cambrian period, as the shrimp nervous system hasn’t changed much since then. This would imply that there are tens to hundreds of quintillions of sufferers inhabiting our earth. The SWP’s long term goal is to slightly reduce the suffering of 0.0004% of them (400 billion farmed shrimp) for around 20 minutes over their lifetimes. This would imply a yearly suffering reduction of 0.00000002% over the malacostran family.
If you still aren’t convinced by all these arguments, I will put forward something more analytical, based on neuron counts. The SWP criticises neuron counts alone by mentioning synapse density and topology, neuron size, conduction velocity, refractory period, and inter-neuronal distance. Funnily enough, on all of these markers, shrimp fall orders of magnitude below humans. Their conduction is slow, neurons large and widely spaced and their synapses sparse and simple. The neuron count measurement is the most generous I could reasonably use.
The human brain contains approximately 86 billion neurons, but consciousness researchers theorize that only about 10% actively participate in generating conscious experience. This gives us 8.6 billion conscious neurons per human. Let’s call this “one sentium”, the conscious capacity of a single human being.
Applying the same logic to shrimp, with their 100,000 total neurons and assuming the same 10% participation rate, each shrimp contributes 10,000 neurons to conscious processing (not unreasonable based on the architectures of their brains), simple arithmetic tells us that 860,000 shrimp equal one sentium of conscious capacity.
But not all sentiams are created equal. Shrimp lack a bounded sense of self, memory beyond a few seconds, cross-modal sensory integration, and any framework for complex experience. At best, a shrimp sentium would encode only the most surface-level sensory experience: raw sensation without context, meaning, or emotional depth. Think of the mildest irritation you can imagine, like the persistent squeak of a shopping cart wheel at Walmart.
A typical Walmart hosts about 550 shoppers at any given time, all of them pushing those squeaky carts. That’s 550 human sentiams experiencing mild irritation. Each electrical stunner processes approximately 500 million shrimp annually, equivalent to 581 sentiams of conscious capacity. The stunner reduces their suffering from ice slurry death, which takes about 20 minutes.
I’ll ask the question, is this worth $100,000? Is this even worth $10? $1? 10¢?
It is likely that installing a shrimp stunner reduces global suffering as much as making the carts in a single Walmart less squeaky for 20 minutes a year. Or perhaps not at all.
The Shrimp Welfare Project wants shrimp to suffer so they can have a new problem to solve.
While they invest millions into speculative welfare gains for shrimp, the same effort and resources could fund malaria nets to save children’s lives, deworming programs to save children’s lives, vitamin A supplementation to prevent blindness, disaster relief, tuberculosis and HIV treatment, mental health treatments, maternal health services, lead paint removal, school feeding programs, safe water and sanitation projects and so many more proven efforts that actually reduce suffering.
I think you make some interesting points here, but there are two points I would disagree with:
First is “The Shrimp Welfare Project wants shrimp to suffer so they can have a new problem to solve.” This claim is made with no supporting evidence whatsoever. You don’t even argue for why it might be the case, and show no curiosity about other explanations for this. They claim to disagree with you, so clearly they have ulterior, malicious motives. (I would say knowingly creating a charity that doesn’t solve a real problem, just to be able to say you’re solving a new problem, is quite unethical!) Why is it so hard to believe the people who founded SWP did so with the intent of reducing as much suffering as possible, and just happened to be incorrect? What makes you completely dismiss this hypothesis so much that it isn’t even worth mentioning the alternative in your article?
Second is “At best, a shrimp sentium would encode only the most surface-level sensory experience: raw sensation without context, meaning, or emotional depth. Think of the mildest irritation you can imagine, like the persistent squeak of a shopping cart wheel at Walmart.”
I don’t see how the second sentence follows from the first. When I imagine a migraine, the worst pain I personally have ever experienced (being a rather fortunate individual) it doesn’t seem to me like the reason I am suffering is because of the context, meaning, or emotional depth of my pain. I’m suffering because it hurts. A lot. It doesn’t seem that complicated. It seems like it would be much more principled, using your analysis, to treat 860,000 shrimps freezing to death as suffering equivalent to one human experiencing the sensation of freezing to death, not experiencing mild irritation. I say “experiencing the sensation of” because things like being aware of one’s own mortality does seem like a thing that’s out of reach of a shrimp. So it’s not equivalent to a human actually dying, in my view, but freezing to death is likely still quite unpleasant, and not something I’d do for fun, and I’d much rather experience a squeaky wheel at Walmart even if I was fine as soon as I lost consciousness and had no chance of mental trauma from the incident, which I think still matches the shrimp equivalence.
What I still think makes this article interesting is that 550 humans experiencing the sensation of freezing to death across twenty minutes is bad, but not as bad as even one human death, which could be prevented by orders of magnitude less cost than a shrimp stunner. So even despite this article’s flaws I still think it’s a good article on net and worth engaging with for a proponent of shrimp welfare.
While a reply isn’t required, if you are going to engage with only one of these points, I would prefer it be the first one even though I wrote a lot less about it. The second point doesn’t actually change the overall conclusion very much imo, but the first point is generally quite confusing to me, and makes me less confident about rest of the article given the quality of reasoning in that claim.
I first want to respond to the mention of my statement that the Shrimp Welfare Project want shrimp to suffer. I did not want to frame my piece as a direct attack on the project, and rather as an exploration of shrimp consciousness and suffering capabilities, as this aligns more with my interests. I wrote my first draft without closely reading their output, from first principles and my own research. I independently read much of the literature on shrimp brains, and have read much of what has been published in the neuroscience of consciousness over the last year. What surprised me, when I started reading the rethink priorities and SWP literature, was that they had read the same papers as I had, and had chosen to misrepresent a lot of the information. They mention findings in crabs, insects, worms and fundamentally different organisms as evidence for shrimp sentience. They stack probabilities based on their own assumptions on top of each other, and have made the justifications for these probabilities and insights unreasonably difficult to find. Their argument against neuron counts as a proxy for suffering and sentience weakens their argument for shrimp sentience, as it mentions factors like neuron density, which is lesser in shrimp. This argument is, however, presented as a counterpoint to certain critiques of the project.
“It just intuitively seems like they are.” This is proposed as a rebuttal for critiques of the shrimp welfare project, not very convincing to me, yet they claim that those who don’t support them are “irrational, evil or both”. I find that making that claim with sparse, scattered and unclear evidence is not great, and paints anyone who opposes their views as as flawed person.
I would prefer if they had purely appealed to emotion and provided philosophical arguments, but bringing in empirical research, and picking and choosing the evidence that supports their argument weakens it in my view.
As for your second argument, I would like to point you to my mention of the ACC. Pain is processed in your brain, not in the pain receptors. You probably evolved the ability to suffer, and I doubt it is an inherent component of consciousness or matter. Your personal experience with migraines does not relate to shrimp as your nervous system evolved independently. I understand the desire to empathise with shrimp, and to imagine them freezing to death and suffering, but they can’t experience anything remotely similar to your migraine.
My arguments were meant to compound, not to be taken independently. Shrimp are probably not conscious, they probably can’t feel pain, and even if they could it would be an extremely basic and surface level unpleasantness. There are millions of neurons in your brain encoding negative signals when the shopping cart is squeaky, orders of magnitude more than a shrimp freezing to death. What would make the experience of their neurons stronger or more morally relevant? I personally believe that, if shrimp can experience, it would just be the basic substrate of experience with no valence at all.
In my perspective, I was not attacking anyone but was mentioning something inherent to humans, however rational they may be. When you want to believe something, it is very easy to convince yourself that it true.
I realize it was a mistake to phrase it that way.
If the above is true, I think this is really good information that would have been very nice to have cited within the article. That would make me a lot more skeptical of SWP and of their conclusions, and it’d be great to see links for these examples if you could provide them.
Especially this paragraph:
“It just intuitively seems like they are.” This is proposed as a rebuttal for critiques of the shrimp welfare project, not very convincing to me, yet they claim that those who don’t support them are “irrational, evil or both”. I find that making that claim with sparse, scattered and unclear evidence is not great, and paints anyone who opposes their views as as flawed person.
I agree with the value claims in this paragraph completely, so if you have sources for those quotes I think that would be very persuasive to a lot of us here on this site, and it might even be worth a labelled edit to the main post.
All is here. The debate is not about the numbers but about the definitions. Suffering in more complex animals plausibly evolved out of mere damage detection. Is it different? Admittedly. But the difference lies along a continuum. No lizard ever woke up one morning as a mammal, suddenly capable of suffering, while its father merely detected damage. Reality is not black and white, it is shades of gray. Remember Yudkowsky’s old post “0 and 1 are not probabilities”.
In the present case, I am not defending shrimp, and the arguments are persuasive, my impression, however, is that the priors are doing most of the work in this discussion. The disagreement is more about priors concerning the gradation nociception ⇒ suffering than anything else. It’s really difficult to decide.
I think that is a good interpretation, but it is important to consider whether they are capable of experiencing the suffering at all. I think consciousness is actually quite complicated, and I don’t think shrimp meet the criteria for it.
I feel like you’re double-counting the difference between humans and shrimp when you separately claim “860,000 shrimp equal one sentium of conscious capacity” and that ice-slurry-death-for-a-shrimp is like squeaky-shopping-cart-for-a-human.
(I didn’t read carefully and this is not necessarily my main disagreement.)
Distinct measurement of quantity and quality of conscious experience, they can compound
Given how many well-informed people disagree on the origin and intensity of suffering and consciousness, your conclusions feel extremely confident.
You say a shrimp stunner, which prevents in the order of a billion shrimp a year from suffocating to death, reduces suffering as much as making the carts in a single Walmart less squeaky for 20 minutes a year.
I am pretty sure that the vast majority of and animal welfare scientists would disagree strongly with that.
For instance, someone who worked on the moral weight project said that:
“As a philosophy of consciousness PhD, it’s not just that I, personally, from an inside point of view, think weighting by neuron count is bad idea, it’s that I can’t think of any philosopher or scientist who maintains that “more neurons make for more intense experiences”, or any philosophical or scientific theory of consciousness that clearly supports this. ”
Source : https://forum.effectivealtruism.org/posts/E9NnR9cJMM7m5G2r4/is-rp-s-moral-weights-project-too-animal-friendly-four?commentId=T2TsnfPFy6jgs3j4p
Moreover, it’s worth remembering that if your advice is wrong, this would have terrible consequences. If you manage to convince one donor to switch their donations, you would cause millions of additional shrimps suffocating to death. Of course, maybe you are right, and I think it’s worth discussing the topic and questioning the assumptions.
But you are doing a public post with clear cut confident advice, and I think doing that before at least having a large number of competent people to agree with you is irresponsible.
The Shrimp Welfare Project is widely criticized.
Citing a single philosopher’s opinion doesn’t really convince me of the science. I also didn’t use the neuron count as my whole argument, it was one of them and I’m happy to admit that it isn’t all inclusive, which is why I made other arguments too.
There is an almost unquantifiable number of living organisms on earth, and the definition of life isn’t even that clear. If you believe shrimp suffer, then the 20 minutes of their life when they are harvested being a little more unpleasant (not clear that this is even the case with stunners), doesn’t represent a “terrible consequence” in my view. It makes no different at all. As I mentioned in my piece, farmed shrimp represent 0.00000002% of the Malacostran family.
These views are not controversial, they are evidence backed (unlike philosophy of consciousness), which I wrote another piece criticizing, you may find that interesting too.
I think funding projects based on vibes isn’t good, and this project demonstrates vibes with percentages stacked on top of them.
“If you believe shrimp suffer, the 20 minutes of their life when they are harvested being a little more unpleasant [...]”
What a wild way to describe suffocating to death. From an evolutionary standpoint, it would make sense that dying would feel like something horrible you’d want to avoid. If I try to hold my breath for too long, I feel horrible, and I don’t think it would be that different even if I were just able to feel “raw sensation without context, meaning, or emotional depth”.
Regarding the other point, I don’t see why the fact that shrimp suffering is a small percentage of the Malacostran family’s suffering is relevant. Yes, there are tons of wild animals. And their suffering is likely to be pretty large. This is why the field of wild animal welfare exists.
But just because there are quintillions of wild animals, this doesn’t mean that helping billions of shrimps isn’t good. That’s still a large number of individuals that we can help, so it’s good to do so. It even means we should devote more effort to the topic than just having a single charity.
As an analogy, I don’t ignore a friend who is hurt because they represent less than 0.000001% of human suffering.
From my standpoint, it feels like you’re saying that the implications of having to care about wild animal suffering would be so big that we have to reject the premise. It feels like when people often fail to acknowledge that cows are likely sentient when they eat them, because it would mean confronting a significant moral issue. But maybe I’m entirely wrong, please feel free to correct me.
What is your subjective probability that shrimps can experience suffering?
My probability is pretty low but I still like SWP, so either we disagree on just how low the probability is, or we disagree on something else.
Closer to 0% than anything else.
I could make the claim that increased entropy is suffering, and that killing anything increases entropy, so accelerating shrimp death actually increases suffering.
I would put the probability of that much higher than the probability of shrimp suffering in any morally relevant way.
Still low
So like, 1 in 1000? 1 in 10,000? Smaller?
Even if shrimp consciously experience pain or suffering, my question is, why do we think electrocution is more humane than freezing?
The idea of freezing to death sounds horrible because we are warm-blooded animals. In cold blooded animals, cooling gradually slows metabolism inducing torpor. I would have thought for a shrimp, ice slurry immersion would be a gentle method of putting them under anesthesia; sounds like that takes a minute. Do they behaviorally indicate pain or aversion? I’m more surprised that an ice slurry kills them. Apparently pink shrimp (the kind people eat) thrive best in ocean waters between 0-8C and have been found living in −2C waters (wikipedia).
They do show reflexes and grooming behaviours for injured antennae so there are some basic pain responses. I agree that the difference in suffering between electrocution and freezing is probably marginal at best, whichever way you go. The ice slurry also can crush and suffocate the shrimp if they survive the cold, but mostly it involves thermal shock, due to the quick change in temperature.