Do boiling crawfish suffer?

Boiled crawfish.
Image credit: Giovanni Handal via Wikipedia

Recently I visited one of my cousins and, as is tradition for a lot of people this time of year, we had a crawfish boil.  Eating boiled crawfish (crayfish for you non-Cajuns) is an ever present activity in southern Louisiana, at least when they’re in season, and I’ve had my share over the years.  Although for me it’s a mostly social thing because I can take or leave crawfish as a food.

Anyway, it had been a while since I observed the actual cooking process.  When the squirming wriggling mass of crawfish are lowered into the boiling water, I’ve always had a moment of dread and mortification, wondering how much these creatures are suffering in their final moments.  And  how long they remain alive in that pot.

When I was a boy, I mentioned this once or twice, and was teased for it, both by adults and other kids, for essentially being concerned about the welfare of “mud bugs.”  At the time I accepted this as a correction for attributing too much intelligence and feelings to these creatures.  But the disquiet each time I saw it never went away, although I eventually learned to keep my mouth shut.

In retrospect, after seeing other kids get the treatment over the years, I now see the teasing as a defensive reaction.  No one wants to consider that we may be subjecting these creatures to unconscionable suffering.  Far easier to conclude that they have no real sentience, and to squash any sentiment that they might, particularly in kids who might go on to ask difficult questions.

Pain in crustaceans such as crawfish, as well as invertebrates overall, is a difficult issue.  The evolution of vertebrates and invertebrates diverged from each other long before central nervous systems came along, so many of the structures we associate with cognition and pain are either radically different or missing.

Even in vertebrates, we have to be careful.  Vertebrates have specialized nerve cells throughout their peripheral nervous system called nociceptors, which are sensitive to tissue damage.  Signals from these nociceptors are rapidly relayed to the spinal cord and brain, where it usually leads to automatic responses such as withdrawal reflexes or avoidance behavior, as well as changes in heart rate, breathing, blood pressure, and other metabolic functions.

But, as counter-intuitive as it sounds, nociception by itself is not pain.  Pain is a complex emotional mental state.  Neurological case studies show that in humans it happens in the forebrain, the thalamo-cortical system, where the right kind of lesions on pathways to the anterior cingulate cortex can knock it out.  This means that the processing happening in the brainstem is below the level of consciousness, and that the behavior associated with it, when seen in other species, is not by itself an indicator of conscious pain.

This is an important point, because a lot of the material out there confuses nociception with pain, citing things like protective motor reactions and avoidance behavior as evidence for pain.  But pain is a higher cognitive state.  To establish that it’s present requires demonstrating that the animal can engage in nonreflexive operant learning and value trade off reasoning.

All vertebrates appear to display at least incipient levels of this more sophisticated behavior, indicating that all vertebrates feel pain.  Although in the case of fish, many species are missing a type of nociceptive fibers, c-fibers, which transmit the signals that lead to the long burning type of pain associated with prolonged suffering.  These fish appear to suffer the sharp pain when an injury is incurred, but not the long burning pain that land-animals experience.

However, nociceptors haven’t been found in most invertebrates, either of the fast sharp variety or the long burning kind.  This has led many to conclude that they don’t feel pain.  However, many invertebrates do show some reflexive reactions similar to the ones associated with nociception in vertebrates, which seems to show they have alternative interoceptive mechanisms for accomplishing similar results.

Perhaps a more difficult issue is whether they show any signs of the cognitive abilities required for pain in vertebrates.  Todd Feinberg and Jon Mallatt, whose book, The Ancient Origins of Consciousness, is my go-to source for this sort of thing, lists crayfish as demonstrating global operant learning and behavioral trade offs.

Following the citation trail, the paper that reaches this conclusion shows that crayfish, while having a pretty limited repertoire of behaviors, can nonetheless inhibit reflexive responses, and change responses depending on value based calculations.  This is pretty much the same capability in vertebrates associated with the capacity to experience affective states, such as pain.

That would seem to indicate that the crawfish, while possibly not experiencing pain as we understand it, nonetheless are in distress.

I read somewhere that lobsters being boiled can live for up to three minutes.  (The experiments to figure that out can’t have been pretty.)  Hopefully, crawfish, being smaller, die quicker.  And hopefully they lose consciousness quickly.

Some countries ban boiling of crustaceans alive, requiring that cooks kill the animal prior to boiling them.  Apparently there’s a device you can get that will shock the head of a lobster, killing it instantly, or at least rendering it unconscious.  Unfortunately, even if it’s anatomically feasible, the idea of using something like that on the hundreds of crawfish about to go into a pot isn’t very practical.  There’s just too many packed too closely together.  Some people advocate freezing first, but it’s not clear that’s a humane way to go either, and doing so with a large cache of crawfish is, again, not practical.

So even if people could be convinced that there was suffering to be concerned about here, I doubt there would be much change in the technique, although it might lead to less people wanting to eat them in the first place.

There is also the fact that lobsters only have 100,000 neurons, less than half what fruit flies and ants have, and only about a tenth of what bees or cockroaches have.  I couldn’t find anywhere how many crawfish have, but I suspect it’s comparable to the lobsters.  In other words, the resolution and depth of their experience of the world is extremely limited, far more so than many other animals whose welfare we typically disregard.

How much of a difference should that make?  Is it right to think of them as conscious?  Does the fact that they themselves have no empathy and couldn’t return ours, matter?  How concerned about this should we be?  Should we follow the example of the countries that outlaw boiling lobsters alive?

20 thoughts on “Do boiling crawfish suffer?

  1. I think your focus on sentience is misplaced. If an animal has a nervous system it is likely they can feel pain, which is a mechanism to avoid damage to one’s body. If I accidentally step on my dog’s foot, he yelps and withdraws. I am fairly certain he feels pain. How do you think he would react if dropped into boiling water? (I used a dog as an example as we all tend to be emotionally linked, one way or another, to them).

    My point is not that we should never inflict pain on any being with a nervous system, my point is nature is designed that to survive you must kill and eat your prey. So, a lovable bunny rabbit, let lose in your garden will dig up your carrots and eat them … alive! To live is a dance with death. We have not yet the technology to be able to live without killing something (animal or vegetable). It is a part of life.

    When dispatching animals for consumption, the ethical thing to do is minimize their pain. To do otherwise is unconscionable. Whether they are sentient or not is another ethical quandary altogether.

    Liked by 1 person

    1. No argument that dogs experience pain, but c-elegans worms, jellyfish, leeches, or other creatures without a brain or central ganglion? That seems like an assertion that requires justification.

      Definitely we have no choice but to consume life. Any organism that’s not at the foundation of the food chain has no choice in that. I’m not advocating that we don’t, or even that we don’t eat meat. (I’m not a vegetarian.)

      I don’t mean sentience in the science fiction sense of sapient intelligence, but it in the original sense as the capacity to feel and perceive.


    2. “We have not yet the technology to be able to live without killing something (animal or vegetable). It is a part of life.”. Actually there is such a thing called cultured protein. Meat can be lab grown with a fraction of the emissions or space, and can be formulated to be healthy. It’s just a matter of making it profitable, and people’s acceptance to eat it.


        1. I personally don’t boil crawfish (or lobsters or anything else). I’ve never been comfortable with it. But I have to admit I eat at other people’s crawfish boils. And unfortunately, putting them in alive is standard practice.

          Liked by 1 person

  2. As a meat-eater, I do look forward to a time when “meat” doesn’t come from living animals. Also, as a meat-eater, I absolutely subscribe to circle of life; just about every form of life eats some other form of life.

    As a former sport fisherman, the question of suffering (fish, in my case) is one I’ve considered. Does the obvious appearance of pain equate to the suffering we associate with pain? What about a robot fish programmed to react the same way?

    Certainly an environmentally conditioned agent will have a variety of programmed responses to pain. Fish flop in hopes of finding water or escaping damage. I see the same thing if I swat a large bug and don’t quite kill it instantly. It thrashes as if it’s in pain.

    Which seems to raise the interesting question of things that appear as if they were conscious versus things that really are conscious. Externally, they seem the same, but subjectively there ought to be a big difference.

    (You’ll remember I mentioned Janet, the AI from The Good Place, another example of appearing conscious.)

    I’ve been thinking about the mirror test. There are lower animals that have passed it, fish, ants even. (I can’t help but imagine any mark placed on an ant would be big in proportion to its body and thus noticeable on its own to the ant as foreign impingement.)

    I’ve read about variation with the mirror test, both among species members and in how long it takes for an effect to appear. At first blush, it almost seems that the simpler the animal’s neural net, the faster it can be programmed.

    This seems to make sense. A simpler NN would be faster to program with new input. A more complex one would have the inertia of all its interconnected weights. New input would be slower to change that.

    The difference between a speed boat and an ocean liner.

    It all suggests to me crawdads are just simple neural nets reacting to a (literally) life-threatening situation. I very much doubt there’s any sense of, “OMG! I’m going to die!!”

    Thing is, I’ve caught the same fish moments after releasing it. They really do seem a form of biological robot.

    Liked by 1 person

    1. Definitely, one of the biggest cautions in biology, which often isn’t heeded, is to be careful not to project our own experience on animals. We’re empathic beings, and we recognize common impulses and experiences in all kinds of animals. It’s the most natural thing in the world to think that the simple behavior we’re seeing is accompanied by the same experience we have when engaging in that behavior, but it’s very frequently a mistake.

      On the mirror test, Gordon Gallup, the original designer of the test, is convinced that most scientists don’t do it right, that those scientists are fooling themselves, seeing things that aren’t there. His attitude is that only great apes have conclusively passed it, and possibly elephants and dolphins.

      I hadn’t heard that anyone was claiming ants had passed it. Interesting. The lowest level organism that I had heard were cleaner wrasse.

      I personally don’t think the mirror test, at least as commonly administered, is that significant. Self awareness isn’t a binary thing, not something an animal either has or doesn’t have. Just about any animal with distance senses is going to be aware of their own body and its relation to the environment. And being aware of your own feelings and attentional state are arguably levels of self awareness. But metacognitive self awareness seems to be much rarer.

      Definitely the nonreflexive capabilities of fish seem very limited. And a fish is a genius compared to a crawfish, which essentially is a giant bug. So I agree that their distress doesn’t come with anything like the existential despair that would exist for a human having the same experience.

      Liked by 1 person

  3. I’m inclined to think we should assume creatures that exhibit pain are experiencing pain. It doesn’t hurt (no pun intended) to play it safe. But of course there’s a limit to how far people are willing to go to eliminate the possibility of suffering, and unfortunately that limit is different for different people.

    But I know what the feeling you mean, and I suspect you’re right about the defensive reaction. A few years ago I went out with a lobster fisherman to catch mackerel (as bait for lobsters). Watching them flop around for a long time on the deck was horrifying, and I had to fight back a childish meltdown (which I did have as a child…a traumatic crab killing experience that was). Oddly, I had no trouble taking home a fish and gutting it and cooking it after it was dead. Gutting it was gross, but strangely satisfying. I felt the need to prepare it well and make it as delicious as possible as a sort of atonement, or to prove the suffering of this poor fish was not for nothing.

    Liked by 2 people

    1. I have the same inclination. I just had to kill a wasp and made a point to make it quick. Given the size of their nervous systems, it’s unlikely they suffer in anything like the way we understand suffering, but I’d rather not take chances. And anyway, getting in the habit of being callous toward the possible suffering of creatures we’re not sure have the capacity to suffer, arguably make it easier to rationalize being callous to creatures where there’s not any doubt.

      On the other hand, it’s a more difficult matter for hunters, fishers, people in the livestock industry, and scientific researchers. That’s where the research into the distinctions becomes important.

      I think the worst killing I ever saw was a shot squirrel. It flopped around in its death throes for a long time. My friend who had made the shot, and was an experienced hunter, said something like, “They go insane for a while. Just leave him be. He’ll stop eventually.” Afterward I helped him clean it, and we took the meat to be added to a family cookout pot. I was actually glad to not be around when it was served.

      But there’s a lot to be said for making sure that when animals are harmed, it’s for a clear benefit.

      Liked by 2 people

      1. I’ve never heard of eating squirrels. I don’t blame you for not wanting to be around for that meal! Squirrels are so cute, it’s hard to watch something like that.

        So true about the livestock industry, etc. To feed our meat-centric society, we end up raising animal in horrible conditions. I think if we had to see where our food comes from and watch it die, at least some of us would think twice about how much meat we eat and where we’re buying it from. Costs would go up (Whole Foods, whole paycheck), but for Americans, it wouldn’t hurt to eat more vegetables. Well, it might hurt a little. 🙂 When I think of the water it takes to grow the crops that feed animals, meat seems astonishingly cheap these days. A five dollar rotisserie chicken can be made into several meals. Leftovers go into some sort of casserole or soup—chicken enchiladas, chicken pot pie, chicken coconut curry—the possibilities are endless. That stage of Mr. Costco Chicken lasts several meals for two people. Then I make chicken stock from the carcass and freeze it, which means I hardly ever buy chicken stock. Then Geordie gets the remaining meat that falls off the carcass, as well as the carrots that cook with it. That’s a lot of bang for $5. I’d gladly pay more for a happy chicken that I don’t have to roast myself, but those are hard to find. And, oddly, the roasted chickens you see in nearly every grocery store are usually much cheaper than the ones you have to roast yourself. That’s another thing that boggles my mind.

        Then again, this world we’re living in is too complicated for my little mind.

        Liked by 1 person

        1. I actually wouldn’t have a problem eating less meat. The problem is that society is mostly calibrated for meat eaters. It’s easier today than it used to be to get vegetarian options, but they’re still fairly limited, and most of them I simply find unappealing. A student worker from India told me that she finds it much harder to be vegetarian here than in her home country.

          Maybe lab grown meat will come along and make this dilemma moot. As cheap as meat is today, manufactured meat might end up being even cheaper, and much more humane. Of course, if we stop growing our meat, the population of domestic animals will crash dramatically. Which reminds me of this SMBC:

          Stuff prepared in mass is usually cheaper than stuff you do yourself. Economies of scale and all that. Which is great when what you want is what a lot of other people also want. When your tastes are unique and there’s no mass production for it, capitalism’s magic seems less…magical.

          Liked by 1 person

    2. I’ve always appreciated cultures that, in some way, honor the animals they kill for survival. I’m entirely comfortable being an apex predator (damn straight), but, as a highly intelligent predator, wanton waste and disregard for life don’t need to be part of that.

      Liked by 1 person

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