+zoffinger . The question of fish pain is controversial. There are scientific data that suggest hooks in fish mouths are not painful journals.plos.org/plosone/article?id=10.1371/journal.pone.0100150, so this suggests they definitely do not react to noxious stimuli like humans, but there is no scientific consensus on this topic. Some scientists look at behavioural changes and think fish might "feel pain" as they act differently when injected with acids or bee venom, while other scientists have found the behavioural criteria are unreliable and cannot discriminate between pain and other non-pain states like irritation. These scientists also point out the nervous system and brain of fish are probably not sufficiently well developed to "feel pain" emotions like birds, mammals or humans. For more information on that side of the equation, see onlinelibrary.wiley.com/doi/10.1111/faf.12010/abstract.

Hi there, check out Victoria Braithwaites speech called Do Fish Feel Pain and Why Does it Matter? Here on KZfaq. Fascinating.

@@sydneyfishsave1685 there is also this - "Reasons to be skeptical..." www.tandfonline.com/doi/full/10.1080/23308249.2023.2257802

ikijime well said

Any particular kind of wire you recommend that I can use to thread the spine without buying a kit?

@@insomb maybe a stiff stainless wire like mason single strand wire leader in 325 - 400 lb ?

​@@ikijime Thanks. Very useful site btw.

I saw you cut where the gills are to bleed the fish out, but I also think it could be a good idea to make a cut where the artery is at the tail muscle. Anyway, to destroy the spinal cord, you don't really have the choice to cut there.

I want fish tasting better that why

Thanks. Maybe they just don't like the music (and I don't blame them !)

Yes, the ikigun is a great tool, available from www.ikigun.com/

Yes, some people use the wire but is not necessary to kill the fish, destroying the brain does that by itself without any other process needed. However, running the wire down the spinal chord does kill the nerves innervating the swimming muscles, which stops the post mortem shivering which can occur in some species like tunas. This is the sort of detail that ensures a fish will get the maximum price on the japanese sashimi market, but it is an unnecessary complication for scenarios where fish are used for home consumption. Feel free to do the wire thing for a marginal improvement in flesh quality (bleeding and icing will give the major improvements), but the wire down the spinal chord won't improve fish welfare as its already dead once you destroy the brain by iki jime.

@@ikijime awesome thanks for replying

No, the wire is not necessary to kill the fish, destroying the brain does that by itself without any other process needed. However, running the wire down the spinal chord does kill the nerves innervating the swimming muscles, which stops the post mortem shivering which can occur in some species like tunas. This is the sort of detail that ensures a fish will get the maximum price on the japanese sashimi market, but it is an unnecessary complication for scenarios where fish are used for home consumption.

Of course fish feel pain. They are capable of feeling pain far worse than most people will ever be unfortunate to feel. A species could not exist with out being capable of feeling horrible pain & fear.

@@samlancaster3130 I'm going to assume your drinking or on some other drug because I find it depressing that someone so insanely ignorant could be in the humane gene pool. You have so much to learn to even be close to understanding what is going on that I'm not even about to waste my time trying to educate you because it's clear you wouldn't get it or even care enough to want know the truth.

@@MrWhiltetail yes, isn't the whole point of pain to help animals stay alive? If they don't feel pain then they have to feel some kind of sensation when they are injured, or like you said they wouldn't have lasted this long and thrives this well as a species.

@@Balen- Yes. Just like with humans. It may be acceptable by many & maybe even legal to cause horrific pain because it's "just" a fish, etc but it's wrong. I wish science could find a way to allow people to feel the pain they are inflicting on an animal of any kind. Cruelty to animals would suddenly cease & there would be tremendous remorse around the world.

Ikijime is the brain spiking process. Once the brain is destroyed the fish is humanely killed, and the benefits to fish welfare have been achieved. The subsequent bleeding and icing can be done in various ways and to be truthful, the correct arteries to cut to maximise bleeding will vary from species to species, but all fish have a ventral aorta to the gills where blood pressure is highest so that is what we showed. Cutting caudal vein is fine for tunas, but not necessarily best for other species, while you can wire the spinal chord if you want, but this is really unnecessary for most intents and purposes. Feel free to wire the spinal cord if you want the ultimate in flesh quality, but we didn't show that as we want new people to try this for fish welfare - we don't want to make the process seem more difficult or complex than it needs to be.

Yes, but as I have said below several times, once the fish is dead what you do to it after the brain spike is irrelevant from the point of view of welfare. Feel free to wire the spinal cord if you want the ultimate in flesh quality, but we didn't show that as we want new people to try this for fish welfare - we don't want to make the process seem more difficult or complex than it needs to be.

@@ikijime oh yeah definitely, just would've been nice to have a mention of it, as many people arent even aware that you can increase the storage time that signifanctly, too. For the fish it won't make a difference, no.

Kill and bleed straight away would reduce lactic acid buildup and stress to the fish, so would be the most humane way. If lake water temperature is warm, however >15°C/60°F, you would only have an hour or so before degradation starts. The colder the water, the longer you could stay out before the fish degrades to a point where eating quality is also degraded.

Sorry, not at the moment. What part of the world are you in ? We would love to work in with more universities or governments around the world in order to get this anatomical information out for more species of fish to help more people.

The critical part of the process when it comes to fish welfare is the destruction of the brain. That is why we have concentrated on that aspect. While destruction of the spinal cord can contribute to improving product quality by stopping muscle twitching etc, it does not contribute to fish welfare as it is done after brain death, hence it is an added complication we don't need to cover here. Hope this answers your question.

The ikijime spikes can be bought from places like www.strikebacktackle.com.au/store/listCategoriesAndProducts.asp?idCategory=36, or you can make them yourself by sharpening up an old screwdriver. There is also the ikigun, see www.ikigun.co.nz/ . We now have some brain location info for US bass on the www.ikijime.com website, largemouth and smallmouths. Their body shape means they will lie naturally on their side so we decided with their brain location it was best to go through the side. It is good to catch and release but also usually OK to keep a couple to eat....

That was a spike developed by the Aqui-S company, to use on salmon . They have customised the spike to suit salmon anatomy. For more see www.aqui-s.com/iki-jime

No problems. Please check out our other videos for more information on scientifically validated humane dispatch methods for seafood.

As long as the fish is ikijimed immediately and placed in an ice slurry, no real reason why you can't leave the guts in until the next day - though ideally you don't want to keep the fish in the ice slurry for longer than necessary because of osmotic issues, after 10-12 hours in ice slurry you should be looking to try to get the fish into a dry environment like a fridge or freezer, if you have the option to do so.

Its ok, we dont need to kill fish to survive :) We dont need to kill anyone.

yes, see www.ikijime.com/fish/bluegill/, www.ikijime.com/fish/largemouth-bass/, www.ikijime.com/fish/bass-smallmouth/

pretty sure we did - e,g, see 3.10 in the video. But yes, bleeding out prior to placing in the ice slurry is important to maximise flesh quality.

@@ikijime But doesn't your video show you bleeding the fish out while being placed into the slurry and not prior?

@@papikorabase No, the bleeding is done first (usually into a separate bucket), then into the slurry. So the order is catch fish, ikijime, bleed, then slurry.

As I mention below, the critical part of the process when it comes to fish welfare is the destruction of the brain. That is why we have concentrated on that aspect. While destruction of the spinal cord can contribute to improving product quality by stopping muscle twitching etc, it does not contribute to fish welfare as it is done after brain death, hence it is an added complication we don't need to cover here. Hope this answers your question.

Flesh quality will still be OK when cutting the isthmus then placing on ice, as death occurs reasonably quickly as the fish bleeds out. However best flesh quality and most humane method is to kill the fish first by ikijime before bleeding out as the bleeding procedure is stressful. The stress is avoidable if the fish is killed first by ikijime, and since the heart still beats after the brain is ikijimed, the iki jime procedure does not interfere with the subsequent bleeding.

Depends on whether they are keeping any fish for a feed, or releasing all of them (catch and release). If you are fishing catch and release no need for the ice, but if you are fishing selectively for a meal, and are not eating the fish straight away (within an hour or 2 of it being caught), it depends on the quality of the fish you want to eat at the end of the day. If you don't care about the quality of your food , don't bother with the ice, but if you want high quality food and a long shelf life, ice is a must, especially in warmer climates. Cost of the ice shouldn't come into it - most fish recreationally for other reasons besides saving money at the market, no recreational fisher should be fishing with the primary objective of making the process profitable...

No. The heart still pumps for a while even after the brain is destroyed, as it has intrinsic electrical impulses that control its contraction. Destroy the brain, then bleed, in that order is best practice for this reason - fillet quality does not suffer at all doing it this way.

@@ikijime Thank You for clearing that up.I remember as a kid,my Uncle killed/cleaned a Snapping Turtle I had caught by the creek.He left the innards on a cleaning stump.I thought it was amazing that the heart beat for several days after it was killed.Guess the same goes for Tuna....

@@Bowtie41 Strong natural selection to drive the heart beat intrinsically, otherwise we'd die every time we forgot to beat it.

Yes, this method can be used for all types of fish.

@@ikijime ok, thanks for the quick response

Yes, but as I have said below several times, once the fish is dead what you do to it after the brain spike is irrelevant from the point of view of welfare. Feel free to wire the spinal cord if you want the ultimate in flesh quality, but we didn't show that as we want new people to try this for fish welfare - we don't want to make the process seem more difficult or complex than it needs to be.

Thanks

Brain spiking is scientifically proven to improve fillet quality, by minimising lactic acid build up and a whole range of other measurable biochemical parameters. Sometimes you can even see the difference - for example, kzfaq.info/get/bejne/p9WTfqWhnZfbl6M.html

Use at least 2 x 5 kg bags of ice per 10 L of water (e.g. double the volume of the ice to the volume of water - we are mixing by volume, not weight). In the video the first bag of ice was already in the ice box. It was a cold day. On hot days the best quality slurry would be to use more ice (e.g. 15 to 20 kg of ice per 10 L of water) and/or less water for the same amount of ice so the ice stays at 0°C for longer. You can use even more ice, but for marine fish try not to use more than 30 kg of ice to 10 kg of seawater, or else the salinity of the slurry will be reduced too much and it will tend to make the flesh softer as it takes up the freshwater.

ikijime Thank you for the detailed reply! I really appreciate your response!

all ikijime tools need to be pretty sharp, for example, the ikipik theikipik.com/

and the ikigun www.ikigun.com/

+Monica Gamez Ikijime is the brain spiking process. Once the brain is destroyed the fish is humanely killed, and the benefits to fish welfare have been achieved. The subsequent bleeding and icing can be done in various ways and to be truthful, the correct arteries to cut to maximise bleeding will vary from species to species, but all fish have a ventral aorta to the gills where blood pressure is highest so that is what we showed. Cutting caudal vein is fine for tunas, but not necessarily best for other species, while you can wire the spinal chord if you want, but this is really unnecessary for most intents and purposes and organolepic testing shows the average consumer can't really taste the difference.

ikijime you got that all wrong sir. I hope you do a research and watch a correct ikejime done by Japanese. It wont take a long time for you. And you will look more smart in future.

Monica Gamez obviously he didn't know about that cord thing... Lol

@@iweoldtimer As I said above, once the fish is dead what you do to it after the brain spike is irrelevant from the point of view of welfare. Feel free to wire the spinal cord if you want the ultimate in flesh quality, but we didn't show that as we want new people to try this for fish welfare - we don't want to make the process seem more difficult or complex than it needs to be.

+AnthonyH Sorry mate, i haven't been able to sample a redfin as of yet, but if you still have the specimen, if you bisect it with a hacksaw down the middle of the head, take a pic of the brain location and send the pic to info@ikijime.com, I will be able to sort something out and get the information out there. Thanks for the heads up.

ikijime Little bugger got away from me before I could properly get him. I'll be going back to the same area soon, I'll be glad to help you out when I do.

+AnthonyH That would be great. If you take a pic of the side and top of the head against a blue background before bisecting the specimen, even better and we could use those pics on the website. No redfin around here so we can't do that species at the moment with our current lack of funding without your help.

ikijime Do you also need data on Tench? I haven't pulled any out from my local fishing spot, but I understand they're about.

+AnthonyH if you can get them, its the same story as for redfin, we can use the data.

Hi Steven, after ikijime, you usually bleed the fish in a bucket for a few minutes before placing in the ice slurry. Ice slurries get the temperature down to 0°C /32°F only - the fish does not freeze, so they can be filleted afterwards OK.

Thanks!!! That clears things up for me

The ventral aorta runs from the heart along the isthmus (the "throat latch", or bit under the bottom of the head between the opercula) to the base of the gills , so cutting straight across the throat cuts the main artery from the heart at a location where blood pressure is highest, so its the fastest way to bleed a fish out.

As mentioned previously, since the heart still beats for many minutes after the brain is ikijimed, the iki jime procedure does not interfere with the subsequent bleeding. Best flesh quality and most humane method is to kill the fish first by ikijime before bleeding out, as the bleeding procedure is stressful. The stress is avoidable if the fish is killed first by ikijime.

jenny pop I think you are talking about a "knock on the head". A knock on the head (also called percussive stunning) is also a quick, humane way to kill fish provided you have the right tool with enough weight to get the job done first hit. A small club or baseball type bat is best in this regard. Percussive stunning requires less skill than ikijime, but thats what the ikijime website (www.ikijime.com) and the Ikijime Tool apps are for !

Yes, what you describe is certainly OK, however its important to reiterate that the critical part of the process when it comes to fish welfare is the destruction of the brain first prior to bleeding. So the order is catch, ikijime, bleed out then ice.

Cutting the isthmus cuts the ventral aorta which takes blood from the heart to the gills. So it is the quickest and easiest way to cut all blood flow at a point where blood pressure is highest, so the fish bleeds out the fastest.

Great, thank you.

If the fish is jumping around you have missed the mark. Make sure the tool you are using (spike ? screwdriver ?) is an appropriate size for the fish you are catching , i.e. big enough to do the job. Then look up the brain location at www.ikijime.com and firmly insert the tool into the appropriate spot and wiggle it around. When you get the right spot the fish will tense up and then you will feel its body relax as the brain is destroyed. Most problems are due to people not hitting the right spot, not wiggling the tool enough to destroy all of the brain, or being too timid and not firm enough with the tool to get through the braincase.

ok thank! should try that out.

Simply a case of operator health and safety - especially with a lure with multiple hooks on it in the fishes mouth. At any time the fish can suddenly flick and lodge the lure in your hand or another part of your body - then you have fish AND human welfare issues to worry about, which is no good for either party. It is a fundamental safety issue that is sometimes overlooked.

removing barbed hooks hurt like hell on extracion

Most people would think there is less chance of a dead fish flipping then while alive. It is especially true when one has been hooked while a 30 pound fish is thrashing on the deck.

Yes, removing hooks from the angler, especially barbed ones, can be a character building experience.

Problem with gutting fish before icing is that by disturbing the abdominal cavity you risk introducing a large amount of bacteria into the slurry system at the early stage before the fish is properly cooled down. This provides an opportunity to increase spoilage risk which reduces shelf life. Best to ice the fish down first then gut later once they are cool, or even fillet the slurried fish without gutting (the latter option assumes you are not eating the remainder of the fish besides the fillet - but in some cultures most of the fish is used , even the head can be boiled, so these details vary depending on what part of the world you live in)..

awesome! learn something every day thanks!

+Jay Zarna I have no problems with catch and release of fish, it is an important management tool and especially not a welfare problem if best practice is used as outlined in various codes of practice including those of EIFAC www.fao.org/docrep/012/i0363e/i0363e00.htm, Recfish recfishaustralia.org.au/national-code-of-practice-2010/ , IUCN Guiding principals etc.

Has there been any legitimate research on how catching fish affects them? Because if you go to PETA, they say that catching a fish is so traumatic that when they are released back in the water they either die of shock or they starve to death. Do you think if you release fish it's better to use barbless hooks?

+Jay Zarna Do not listen to PETA, their agenda means they do not let the truth get in the way of what they want to achieve. There has been an enormous amount of scientific research on catch and release over the past 25 years. Almost invariably survival rates of released fish are high (over 90%), and can approach or equal 100% provided best practice methods are used that reduce chances of deep hooking (in the throat, gills etc) by fishing actively and using lures rather than bait, using circle hooks instead of J hooks while bait fishing, using appropriate tackle (strong enough line to pull the fish in quickly), cutting the line on deep hooked fish rather than trying to remove the hook and so on. Barbless hooks are good as they significantly reduce handling time, reducing air exposure. Catch and release of fish from deep water can be problematic due to the pressure change, but survival can still be very high if release weights are used to recompress the fish. For more information on this topic, see scientific reviews such as www3.carleton.ca/fecpl/pdfs/Bartholomew%20Review.pdf and websites such as recfishingresearch.org/gently-does-it/ , www.dpi.nsw.gov.au/fisheries/recreational/saltwater/catch-and-release and www.keepemwet.org/principles-2#principles

+ikijime another good review on scientific best practice for catch and release is www.fecpl.ca/wp-content/uploads/2007/08/Pelletier-et-al-2007-EM.pdf

+Jay Zarna It's highly unlikely for a fish to die or starve to death after being caught by an angler. It's possible the fish they used for that claim were guthooked, and therefore didn't have a snowball's chance in hell of survival. I've heard people say some fish get smart and won't go after a lure that comes past them, but have never experienced it myself. PETA have their heads lodged fair in the arseholes, and should probably consider not telling people how to enjoy their hobbies.

Usually one where one eats the other.

Not saying that doesn't work, but brain destruction is actually a quicker kill than cutting off the head, and not as messy. Iki jime also allows you to bleed the fish properly after you've killed it, while once you've chopped off the head, there is no way for the heart to pump the blood out of the flesh like it does when you cut the isthmus below the gills on an iki jimed fish. So cutting off the head cannot yield the same quality product compared to ikijime because the fish cannot be bled out properly.

I agree, we are looking for funds to upgrade the video and the music will be the first thing to go....

Incorrect. If you have no brain you can't feel anything. You are dead. Paralysis in vertebrates occurs only if you break the nerves along the spinal cord, leaving the brain intact (and the animal alive), and even then your brain can't feel what is happening below the break in the spinal cord. Ikijime destroys the brain, so the fish is immediately dead.

There is certainly plenty of evidence to suggest what fish experience is nothing like what humans feel. For more, see www.researchgate.net/publication/245032250_Can_fish_really_feel_pain and academic.oup.com/icesjms/article/76/1/82/5037898

That is why the ikijime website and phone apps were developed, so you learn about the brain location and DON'T miss the brain....

Unfortunately they have got their osmotic theory wrong. Fish flesh dehydrates in salt water, which is why saltwater fish have to drink all the time. Only at salinities below around 7-8 ppt do fish tend to absorb water osmotically. For saltwater fish an ice slurry made up of 1/3 by weight of seawater and 2/3 by weight of freshwater ice will be around 10-12 ppt salinity, ie, it will be roughly isosmotic to the fish flesh and will neither dry it out much or make it too soggy. Because of this its OK to leave a seawater fish in a seawater slurry for a few hours, but probably no more than 10-12 hours if you want to maximise quality.

The question of fish pain is controversial. There are actually scientific data that suggest hooking a fish in the mouth is not painful (Eckroth et al. 2014 - Physiological and behavioural responses to noxious stimuli in the Atlantic cod. PLOS One doi.org/10.1371/journal.pone.0100150 ). So whatever fish experience, it is a very different experience to what humans have.

In most other parts of the world where water and air temperatures are higher than the UK, bleeding a fish out can greatly improve flavour, flesh quality and shelf life by removing the blood which , after death, acts as a source of nutrients for bacterial spoilage. So bled fish taste better and store better, and the improvement you get between bleeding and not bleeding increases with water temperature.