Humanely killing fish

[TLewis]

Hi all,
I have a major issue with inflicting unnessary suffering upon any living thing let alone fish. It's something that I've always wrestled with. (Fortunately I don't catch enough to be a serious problem - He He)

Seriously though, I found a thread here about killing Flathead humanely and it seems from the posts that the most acceptable way is to dunk the flattie into a slurry of crushed ice in an esky.

Can someone tell me if that really is the most suitable way to put ALL species of fish down. If not, which really is the best way?

Thanks all (I hate cruelty)
Tony

[Gagga08]

I personally don't kill fish very often as well, as i'm largely a catch and release angler. But occasionally if i catch a nice flatty or whiting I will taking it home. I find the best way to kill them is to use the old whacking stick method. A precise blow to the head with a blunt object will quickly kill any species. Aim just behind their eyes, I find this knocks them out quickly. I also like to fillet the fish straight away too, then put them on ice. If your gunna go to all the trouble of catching a fish for the table you may as well keep it as fresh as posible.

[Benno1]

ive heard of that method TL...have'nt practised it tho...you could give it a go...if you can handle watching/timing how long it take for the fish to expire in the extremely cold water...i personally go for the quick cut under the gill line...yes they do thrash for a bit...then straight into the kill bin...then into the slurry...works for us...far from humane i know...what about the iri kiri (correct spelling)...the brain spike???

[TLewis]

Thanks Gagga08
I'm concerned that I might miss a good hit while trying to stop getting spiked.
Any other ideas fro others?

PS: How do I formally thank respondents to posts and threads? I notice that in the left hand profile there are spots referring to thanks etc but I can't find where to use it?

[Orrsum]

see the thumbs up on the bottom ot the thread give it a push....that should do it.

[rhycebullimore]

ikijimi spike (i think i spelt it right). basically a screwdriver sharpened to a point then inserted behind the eye of most fish, piercing the brain/nervous system killing the fish instantly, giving you perfect fillets as the heart actually stops pumping blood. i have done this to a 15kg spainard from full thrashing to not even a gill movment in under 5 secsonds.

[Scott nthQld]

Personally, I just cut the throat, kills fairly quick, but also bleeds the fish, giving a much better tasting flesh. If the heart is still pumping, you will get more blood out of the flesh making for a tastier fillet. You can also go one step further, and cut through the spine, makes death almost instantaneous and the fish bleed out faster, but depending on the size of the fish and how much you want to blunten your knife, sometimes its best to leave that option.

Not the most humane way, but a good compromise between table quality and being humane. Other my disagree, but I only speak from my own personal experience.

Bitey things with circular saws in their mouth cop an accurate, sharp blow to the head with a club, that sorts them out quick smart.

Another tip, when bleeding your fish, do it in some water, they bleed out faster and the water stops the blood from clotting, allowing you to get them into the slurry faster.

[For Steve]

I can relate to this. I love catching them and eating them but really struggle with doing the job of killing them.

Iki Jimi is the way to go. It's like a stainless steel screwdriver sharpened to to point. Push into the "temple" of the fish. It seems quite clinical and kills them very quick. The general rule is slightly behind and above the eye but this varies depending on the species of fish. I mainly keep snapper and you can feel the "temple" quite easily with them laying on their side. Not sure about flathead - perhaps through the top of the head between the eyes???

Here's a link: http://www.fish.gov.au/manual/preparation.php#iki

Cheers
Brad

[jtpython]

I use a long mouth pair of wiss snips they cut the throat clean and fast and then cut the fin let bleed into a kill bin then straight into the esky is quick and simple
Cheers
jt

[TLewis]

Thanks For Steve
Steve, I have copied the text from fish.gov.au about humanely killing fish below for anyone that might be interested. I found it enlightening and I will use that method in future unless anyone can offer good reason why not.
Cheers mate
Tony

To Kill Finfish Using Iki Jime
For maximum product quality and minimum stress to a finfish the iki jime (live killing) method can be used. This instant killing method reduces the accumulation of waste products in the flesh, minimises physical damage (including the loss of scales) caused by the animal’s sometimes violent body movements and keeps the finfish intact apart from a small hole in the head. For best effect the fish must be bled and chilled in an ice slurry immediately after it has been spiked.

In iki jime (pronounced “ick-ee jee-mee”) a spike or awl is inserted directly into the brain causing immediate brain death and the cessation of all motion. Iki jime also prolongs the process of rigor mortis—the natural stiffening of muscle tissues after death. Deterioration of flesh quality occurs mainly after rigor mortis, so delaying the onset and process of rigor mortis through “quick kill and chill” techniques produces a higher-quality product with a longer shelf life.

Some practice is required to perfect the iki jime technique. The position and angle of spike entry required differs between species and one example of each species may need to be cut lengthwise through the head to locate the position of the brain. When spiked correctly, a fish will exhibit a short but violent convulsion (due to the physical stimulation of the brain) before relaxing.

To use the iki jime technique:
Hold the fish firmly and insert a spike into the brain. This should be done as soon as possible after capture.
Bleed the fish by cutting through the top of the gills. Access the gills by lifting the gill cover.
Place the fish in an ice slurry. Use mostly freshwater and freshwater ice to produce a slurry with the consistency of wet concrete and a temperature between –1°C and +4°C for no more than 2 hours.
Remove fish from the ice slurry and process further or store as required.

[blueboy]

Hi Tony, Like you I try to be as humane as I possibly can. I am happy to say I am releasing more and using barbless hooks. As I also like a feed of fish, as soon as I have a "keeper" in the boat, I immediately cut it's throat and break it's neck by firmly bending it's head back. Sounds gruesome but it's all over in seconds. Cheers, Greg

[Ryan.S]

I just slit the throat with a fillet knife, seams to be a quick way. The brain spike method would be quicker i guess, a sharpened screwdriver in the boat sounds a bit dangerous but. No more than a knife i guess but.

[wilcara]

I wonder what is the difference between the icky jimmy thing and just a poke with a fillet knife to the same spot?

[Poodroo]

I have always struggled with the fact that I have to kill a beautiful creature in order to put a feed on the table but I love eating fish too much to not go through with it so I made some inquiries as to what would be the best way some years ago. I have worked in the Aquarium industry for several years (recently returning back to the industry) and I have had the pleasure of working alongside one if not the best and most knowledgeable men in the business. What this man doesn't know about fish is simply not worth knowing. He has taught me several things over the years including how to determine the cause of death via autopsy. Now occasionally we are faced with people bringing in their most adored prize aquarium fish which they have nurtured for several years and grown to near full size but the fish has developed a debilitating disease and needs to be humanely put down. So I ask my mentor just how do we acheive this without making the fish suffer any further? Next I get this long winded and very interesting lecture on the fish nervous system including diagrams produced from his age old collection of books (He is around 80 years of age and still sharp as a tack) and he also covers the metobolic system that fish have. Now he assures me that the fish do not feel a lot of pain but they do sense discomfort. His short answer was the most humane way to distroy a fish was to freeze them because it slows their metabolism right down and they do not sense pain during this process but rather go to sleep. I trust his judgement and wealth of knowledge and have been putting my catches into an ice slurry in the esky since.


Poodroo

[Outsider1]

Thanks Poodro,

I use that method for crabs. Put them in a plastic bag and tie it up to effectively truss them and then into the freezer so they can go off to "sleep" Works a treat and no thrown claws or legs.

A bit hard to do out on the boat though. I have thought about keep them (fish) alive in the bait well but from what I have read this can stress them and reduce the quality of the flesh. So I break the throat and bleed them. Seems to be the quickest and most humane way other than Iki Jimi which needs to be practiced to get right.

Cheers

Dave

[revs57]

The Iki jimi spot is like a temple - there is a soft spot that is located just behind the eyes between the lateral line and the top of the head, it is pretty hard to miss, results are instant, then cut their throat and whack them in the slurry - you'll get the best quality fillets every time. Aparantely fish have an enzyme that caues the flesh to detiorate very quickly if not killed, bled out and chilled almost immediately. The only fish i don't bleed are whiting and flathead - I've never seen blood on the lateral line in those species. As for anything else, Iki Jimi spike it, bleed it out in the slurrey - the results are amazing

cheers

Rhys

[gunna]

I wonder what is the difference between the icky jimmy thing and just a poke with a fillet knife to the same spot?

Not a good idea to 'poke' with fillet knife. Blade is too flexible and you also run the risk of your hand slipping down onto the blade. In my opinion.

[mik01]

I wonder what is the difference between the icky jimmy thing and just a poke with a fillet knife to the same spot?

I do this - use the fillet knife - works a treat.
should get a quantity of clotted blood come out (maybe brain?) and its all over.

I have also simply used the ice slurry - you hear the fish do a couple of jerks and kicks in the esky but they very quickly 'go to sleep'.

I prefer the ice slurry, as I don't have to 'kill' the fish but who knows what is best? everyone has their own method and its what you are comfortable with I guess.

I guess when you look at abbatoirs, they kill with their own version of a 'brain spike' - a bolt bullet to the head, then drain the blood, cut it up and straight to the chiller. its the most humane and keeps the meat in the best condition possible.

therefore the fishing equivalent would be IkeJime

[rhycebullimore]

fillet knifes i have seen snap and if you slip very quick end to what should have been a good days fishing.

[TLewis]

I agree about fillet knives. I have bent the tip of my fillet knife trying to hit the brain of bream.

I reckon a sharpened screwdriver or a small ice pick would do the trick.

With Iki Jime it seems you kill first then ice slurry... what about the reverse of that and kill the fish after it's metabolism has been slowed down? I wonder if the fish suffer major stress as it suffers asphyxiation in the ice slurry.

I wrestle with the ethics of all this because I'm the one in control of this animals destiny. I wonder why it doesn't concern me too much when I pop down to the butcher and buy some steak or chicken? A bit of hypocracy going on here maybe.

Out of sight, out of mind I think. Still, I really want to do the best by the animal.

Tony

[rhycebullimore]

i don't know about you, but personally if i had to choose, i would rather a bullet to the temple,rather than having my throat cut or dying from asphyxiation any day of the week hands down.

[Braddles]

My friend who is an exotic species vet at Highgate Hill here in Brissy maintains an ice slurry. It induces a hypothermic coma. Freezing to death is painless, and some literature refers to a sense of euphoria prior to loss of conciousness. (a mountain climber's toes will freeze and they wont even know, its the DEFROST that is painful).

As temp decreases, basal metabolic rate slows, and sleep is induced. The fish is relaxed at all times, and goes into a deep sleep from which they never wake.

Therefore - an ice slurry is the most humane method of killing fish, that is not subject to error, like beating a fish in the head, cutting its throat and bleeding it to death or other methods described.

The brain spike literature is from the manufacturer - so question its validity... If you do get the pons / medulla (brain stem) - you will kill the fish, but I dont have an MRI on my boat , so I cant be sure I am not poking say the cerebellum proper, and merely inducing a severe head injury... .... All a bit hit and miss (pardon the pun) for me.

[For Steve]

Mmmmmm... the ice slurry idea does make sense. Especially if you're unsure of the ike jimi location for a particular species.

On the fishing knife idea - I have used this in the past but since buying a stainless steel iki jimi tool it's much easier. It slides in smoothly, doesn't bend and is easy to aim. Just a better tool for the job IMO.

Regards
Brad

[2manylures]

Bloody Barbarians.

It's the VET for me!

[wilcara]

Ha ha

I am surprised though, I thought when this thread started that anyone proposing humane treatment of fish would have been proverbially "tarred and feathered"!

I'm very pleased to see so many people at least treating them with the respect they deserve, and not one ridicule.

Except. of course, for 2manylures who has enough money to take a vet fishing with him every time. ;D

[2manylures]

Ha ha

I am surprised though, I thought when this thread started that anyone proposing humane treatment of fish would have been proverbially "tarred and feathered"!

I'm very pleased to see so many people at least treating them with the respect they deserve, and not one ridicule.

Except. of course, for 2manylures who has enough money to take a vet fishing with him every time. ;D

Thanx cobba!

In all seriousness, I don't kill fish for the table, only bleeders for obvious reasons.

Having said that does anyone really think that after X amount of time {drag & fish weight} being dragged around with a hook in the gob that a fish would worry too much about how it was actually put out of it's misery.

The other side to the humane story.

[mangomick]

maybe its time to find another sport or hobby.:-/
next you'll want to carefully wash them and have them face towards mecca

[Nic]

The fact that the Japanese invented brain spiking for tuna, to produce the best sashimi possible, gives the practice extra weight in my book. They're very particular about the quality of the flesh, which can fetch a lot of $$ if it's top quality, so I figure they must be on to something.

We have a stainless iki jime spike and it's really easy to use, you just line the eye up with the false gill plate.

Spiking is so very quick, I can't help feeling it must be better than cutting a fish's throat while it's still alive. We spike and bleed all our reefies and the flesh comes out very white, better than if you put them in a slurry without bleeding them first.

[KGW3]

Good to hear there are some Human's among to cruel dogs that seem to be around... A lot of anglers just throw the fish in the bucket and let if flap around for 20 minutes. When I decide to keep one or two.. I just kill it them at the beach with a sharp knife.. Still makes me feel bad though.. That's why I release 95% of what I catch. I find it hard to "spike" flathead as they have a ver hard skull. I find if you turn them over and cut deeply across the whole thoat, they die quickly..
Unfortunately. we are a meat eating animals... So there is a natural tendancy to need meat or fish in our diets.. You can't save the world from cruelty and also be healthy... Unless you become a Vegan.:'(

[2manylures]

FAIRDINKUM, This is the biggest load of hypocracy & bullshit I've heard/seen in a bloody long time.

I dislike cruelty also BUT, if ya feel that bloody bad about it DON'T GO FISHING as the CATCHING is FAR WORSE than the KILLING.

Join the greenies &/or animal liberation army and they'll educate ya about all the other things in your everyday life that inadvertantly associates you with various forms of cruelty.

YOU GOTTA BE GAGGIN

PS: How many of you use live baits of any description?

[Little grey men]

2 many lures...this site is about educating others who want to know. A lot of people who have landed a fish have thought..now what do I do with it.
Nothing wrong with wanting to know how to despatch of your catch as efficiently and humanely as possible. To some people that sort of thing is important.
Each to his own.

[2manylures]

2 many lures...this site is about educating others who want to know. A lot of people who have landed a fish have thought..now what do I do with it.
Nothing wrong with wanting to know how to despatch of your catch as efficiently and humanely as possible. To some people that sort of thing is important.
Each to his own.

I have no qualms with educating & do take other people's sensitivity into consideration as well as seriously. I will generally do my upmost to help anyone with a genuine honest problem.

However I cannot handle hypocrisy & that is what this is.

Here’s the scenario from a sensitive point of view.

A poor fish is swimming around watching it's back looking out for predators trying to have a feed when all of a sudden it picks up a morsel {possible live bait}

As it swims on to find a little more its head is almost ripped from the rest of the body. The tooth ache is far less painful than the almost broken neck

After a struggle it’s dragged to this great big thing sitting in the middle of the ocean and makes one last ditched effort to swim to safety, all to no avail.

Absolutely terrified this creature is lifted out its natural environment for the very 1st time in its life, hanging on the end of a hook by its mouth, staring at some humungous ugly big scary creature.

Gasping for breath & struggling to free itself from the sharp object tearing at the inside of its mouth etc, etc Need I go on? ...........................

How could anyone show any genuine concern regarding cruelty after committing horrendous acts as above in the 1st instance?

Get real or don't go fishing in the 1st place if ya fairdinkum.... NOTHING SHORT OF MORBID HYPOCRISY!

AND if releasing them makes you feel better then that's even bloody worse.

[Little grey men]

I can certainly understand your thinking...but I guess it's a case of ...don't think about it too much or it will drive you nuts.
I see that you practice catch and release fishing. Do you use a suitable landing net to protect the fish as much as possible? or do you gaff them all because they've already been through hell ? Do you limit their time out of the water or think, nah stuff it, if it can handle a hook in the gob it can hold its breath for another minute ? I think someone with your fishing years and knowledge would have to respect these fish a lot.
A lot of other people respect these fish as well, and that carries over to despatching them quickly and humanely.
Hypocricy or not.....it makes people feel comfortable, so let them feel comfortable.
Thats just the way it works.

ps "big humongous scary ugly face" speak for yourself mate..the fish always smile when they see me;)

[JIMBO99]

I've Personally Never Been Dipped Headfirst Into An Ice Slurry, But Judging By The Burning Hands When I've Dipped My Hands In I Guess It Would Be A Quick And Certain Death, Seriously Though If You Want To Kill A Flathead Quickly, Grasp The Body In One Hand Firmly And The Snout In The Other And Quickly Snap It's Head Downwards Not Upwards Until You Hear A Click Very Quick Death Mate.

[2manylures]

I don't actually boat fish these days {haven't for many yrs} as I don't keep them.

I use barbless hooks for quick easy removal.

I'm also very passionate about my fishing & not only respect the fish but those anglers who do the right thing.

[Nic]

I wouldn't call it hypocrisy, it's just that every human being draws the line somewhere. I don't eat veal because I don't like the way veal calves are treated, but I still eat beef because I feel those cattle have a better life. Don't know if that makes me a hypocrite or not... but I tend to think that hypocrites are the ones who boast about their lofty morals, and I don't believe anyone in this thread has done that. Some are just asking for suggestions, and others are providing them.

As an aside, one of my science colleagues did an extensive practical study on whether fish can feel pain as mammals do. All evidence indicates that fish can feel some discomfort, but not pain as we know it. If you think about it, if fish felt pain at being hooked, wouldn't they swim towards the pressure rather than away? And why do the same fish get hooked over and over, sometimes in the same session?

I personally don't think we need to feel too bad about hooking and reeling in a fish, provided we don't use overly light gear and exhaust it. (Again, my own personal line drawn in the sand!)

[2manylures]

Post Withdrawn;D

[For Steve]

This is how I see it. A member has asked for suggestions on how to best kill his catch to minimise suffering to the fish. He appears to enjoy his fishing and must enjoy eating the fish he catches. If you have a suggestion for this member on how to best kill his catch, then give it.

Regards
Brad

[mik01]

yep - lets get back on track.

can anyone tell me where to get an ikijime tool from please? chandleries sell them?

[Nic]

I got mine from StrikeBack, here is a link to it so you can see what it's like:
http://www.strikebacktackle.com.au/store/TackleAndBoat.asp?cat=3&DocumentID=21

I believe L.Wilson (www.wilsonfishing.com) and Black Pete (www.blackpete.com.au) each do one too, although it may not appear on their website. If you contact them through, they may be able to tell you your nearest stockist.

[KGW3]

2manylures.

I don't understand your Point of view ? Do you fish or not ? If you do and you say catch and release is just as bad as as catch and kill.. You will be extremely outnumbered on this site. I also have a few problems with killing fish, but realise that I am just a member of the the most destructive, cruel and insensitive species on the planet... a Human Being.. And You are what You is...

[castlemaine]

yep - lets get back on track.

can anyone tell me where to get an ikijime tool from please? chandleries sell them?

I bought an cheap flat bladed screwdriver, drilled a whole in the blade then grinded the blade to a point.
I use the blade to brain-spike the fish (my prefered method) and other use is to thread a piece of twine into the drilled hole and spike a mullet and pull the twine through to to tie off as crab pot bait. The screwdriver hasn't badly rusted as yet.
Cheers8-)

[2manylures]

This is how I see it. A member has asked for suggestions on how to best kill his catch to minimise suffering to the fish. He appears to enjoy his fishing and must enjoy eating the fish he catches. If you have a suggestion for this member on how to best kill his catch, then give it.

Regards
Brad

For the very few fish I do kill I've found a quick hard blow to the brain using something with an edge {back of heavy knife, piece of steel or similar} visually seems to be the quickest, less stressful way including spiking

Surprised no-one has mentioned this. ;D

[2manylures]

The fact that the Japanese invented brain spiking for tuna, to produce the best sashimi possible, gives the practice extra weight in my book. They're very particular about the quality of the flesh, which can fetch a lot of $$ if it's top quality, so I figure they must be on to something.

Nic & others, Brain spiking is only for cosmetic reasons. It has absolutely nothing to do with flesh quality.
Prior to this method being used it was clubs or similar, if at all. The Japanese market dictated what they wanted fresh fish to look like when being sold in the wholesale markets. No other reason.

To produce the best sashimi, it was & may still be, best practise too, after cosmetically killing {spiking} the fish to insert a corkscrew into the brain & remove it. Apparantly the brain will transfer a small amount of heat for a short period of time to various parts of a fishes body & partially cook some flesh.

Bleeding of the fish is done by a small slit {app 1/2"} behind the pectoral fin.

Gutting of the fish is via the mouth.

Preservation is by means of ice slurry.

For sashimi, the Japanese prefer the larger/est Tuna as they have a higher fat content.

When all the above have been carried out immediately & correctly you have a fish that looks good, has no bruising, is clean inside, blood free, with pristine flesh & although dead looks as if it came straight out of the water.

[2manylures]

Toomanylures.

I don't understand your Point of view ? Do you fish or not ? If you do and you say catch and release is just as bad as as catch and kill.. You will be extremely outnumbered on this site.

The point I'm making if you cared to read & take it all in is the fact that the catching of a fish is more stressful than the killing. :o >:( :o >:( :o


I'm saying that if anyone has a fairdinkum, heart felt passion about any form of cruelty as has been mentioned here releasing the fish does not justify the cruelty of catching it.

I also believe in each to there own but at least be fairdinkum about your principles & morals.

[KGW3]

2many
I am not judging you on your principals and morals... i just can't see what point you are making.. If it is that fishing is cruel, I agree. Catch and Release.. I'm not sure but the fish gets to live.. But unless we become complete Vegans, we will always indirectly be responsible for some form of cruelty.

[Wahoo]

if its a spanish or a hoo, it gets a good wack on the head

[2manylures]

if its a spanish or a hoo, it gets a good wack on the head

And from a distance. A mate almost lost a finger to a barracoutta/couda showing how to remove the hook;D ;D ;D

[Nic]

Nic & others, Brain spiking is only for cosmetic reasons.
To produce the best sashimi, it was & may still be, best practise too, after cosmetically killing {spiking} the fish to insert a corkscrew into the brain & remove it. Apparantly the brain will transfer a small amount of heat for a short period of time to various parts of a fishes body & partially cook some flesh.
When all the above have been carried out immediately & correctly you have a fish that looks good, has no bruising, is clean inside, blood free, with pristine flesh & although dead looks as if it came straight out of the water.

Wow, that's interesting, I had heard that killing the fish instantly with a spike was invented to keep the flesh in better condition, rather than as a substitute for disfiguring smacks to the head. But I suppose it makes sense that killing a fish very quickly, however it is done, will achieve the desired result (unless you're looking to sell top-dollar bluefin!)

For me, unless it's a mackerel, I think I'll stick to spiking rather than clubbing. I find it a bit easier.

[castlemaine]

Wow, that's interesting, I had heard that killing the fish instantly with a spike was invented to keep the flesh in better condition, rather than as a substitute for disfiguring smacks to the head. But I suppose it makes sense that killing a fish very quickly, however it is done, will achieve the desired result (unless you're looking to sell top-dollar bluefin!)

For me, unless it's a mackerel, I think I'll stick to spiking rather than clubbing. I find it a bit easier.

2manylures does make a good point, never thought of it being cosmetic. I have found though that if I spike a fish in the right area Rigor Mortis is delayed. But then again, when we fish for Blackfish we spike them then bleed them as well. Flesh is perfectly white.8-)

[oldboot]

Now you have to understand that there has always and will always be a bleeding heart sentiment arround killing anything.

But we have to realise lots of animals especilay those at the top of the food chain ( thats us ) need to kill to eat properly.

( " If god wanted me to be a vegitarian, how come he put the wrong teeth in my mouth")

In our modern insulated lifestyle we have be so sepearated from the realities of life & death, many of us fail to realise or understand these realities.

another reality is that almost without exception all fish will come to a violent and grusome death in their natural situation.

Most people on this forum would be basicly humane in their outlook and would not intensionaly make an animal suffer excessivly.
So knowing how to kill a food item efficiently is a reasonable thing to discuss.

one hopes that a fish we catch may have a better death than it would otherwise have in the wild

SO

I think we need to understand that a fish is a long way removed from a human in its make up and its perception.

To start Fish are cold blooded, so their perception of cold will be vastly different to ours....... being cold bloded will make killing by ice slurry much more efficient and humane.

Fish have a much smaller brain that ours, so they don't have surplus capacity for all the emotional bagage that we carry arround.
Much of the fishes "thinking" would be more akin to a reflex and a survival instinct.........I doubt if a fish would have a concept of "terror"...... a whale yes, a fish no.

A fishes mouth is relativly hard and would not have the concentration of nerve endings we would expect in our lips or our hands...... consider that many fish crush shells and coral in their mouths and they have to withstand all sorts of sharp and hard bits on the things thay eat..........so considering what it would be like to have a hook in your mouth is not a usefull paralell.

SO
If we hook and land our fish reasonably quickly, then either kill it or release it efficiently, we should not have the great guilt trip the bleeding heart vegans would prefere we had.

I think what is important is that we kill the fish purposely and as efficiently as we can and not just let it die slowly.

A massive blow to the head kills most things quickly, so does seperating the head from the rest of the body.
Profuse bleeding may not be the quickest but it will get the job done.
A spike thru the brain, if you can do it accurately has to be efficient, if you can do it.
I supose it would be helpfull to cut open the head of the next dead fish you have to get some idea of how things are and where the bits are.

It occurs to me that the brain will not be all that big.
Again we are different... the primary function for our skull is to house the brain, where as the primary function of a fishes skull is structural, a means of mounting a set of jaws and terminating the spine.......next time you pick up a fish look at how much of the front of the fish is mouth.

Personaly I believe that all humans at some time should take responsibility for killing their own food.

Sorry about the deep & meaningfull, but thats the way I see it.

cheers