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killing fish in the freezer?

11K views 81 replies 39 participants last post by  CatSoup 
#1 ·
hi all,

more of a discussion point than anything else.... i have read many many forums where its suggested that if you need to kill a fish you should put it in the freezer......

why is this? wouldnt knocking it on the head be quicker?
 
#3 ·
+1 with the above comment. Some people see this as a "more humane" way to put their fish down. I've seen quite a few people do this with their larger fish, like discus or cichlids. If they have a large tank with an expensive stock, they will then take the fish to a vet to test to see what the fish had (if it was a disease and not old age), so they could treat their tank as such.
 
#4 ·
i'm not 100% sure, but it seems that it would torture the fish before killing it slowly. it would be easier to get it over quickly, because if someone tried freezing the fish, it meas that that they probably cared for the fish and don't want to let it go so easy. they would check on the fish every few minutes, and they would suffer slowly too, though not like the fish. like i said, i'm not sure if what i said is true, but it makes sense to me.
 
#6 ·
I feel like "can't do it" shouldn't be an excuse for anyone to extend the time it takes to kill their fish. If it becomes necessary to kill your fish (or anything, for that matter) you shouldn't be concerned about how it makes YOU feel, instead you should be thinking about the quickest and most painless way to dispatch the poor creature. Anything else is incredibly selfish.

Put yourself in the fish's shoes. If you had a choice, would you rather go out quickly and painlessly or die a slow death in the freezer because someone "wasn't comfortable with killing?"
 
#8 ·
Fish are kind of like reptiles right? In the sense their body temperature is controlled by their environment.


As such a freezer is very humane their body cools and they slip into a coma so to speak before they die, so pretty humane.

Someone please correct me if I am wrong

Sent from a dark corner in my happy place
 
#11 ·
the thing about freezing is it slowly rips apart the cell structure as it works, think about how meat burns in the freezer... and try and decide if you'd want to die like that.

besides the pain factor, it's not instant at all and being instant is the only way to be humane. somewhere, there's an ASPCA (or someone? i forget who) official list of methods of putting animals down, i referred to it when i had to put down a very sick frog and freezing (for any animal!) was strongly discouraged...
 
#14 ·
When the water temps drop the metabolic rate lowers. At a certain point reduced blood flow to the brain induces coma, then the organs shut down and the the heart stops. There is no over stimulation to the nerves.(what we call pain)

As death go that's about as low drama as it gets.

Nothing other than instant traumatic destruction of the brain is more humane.

I put the fish in a small bag of water in the freezer before I leave the house for the day. When I return the frozen bag & the deceased go out to the trash and life goes on.

When I was breeding cichlids I had an Oscar that was my Quality Control Mgr. he handled the culls.
 
#15 ·
Euthanizing anything via freezing is painful and distressing. We had a client that put down a sick bird in the freezer then brought it in for necropsy (pretty efficient way to ensure we wouldn't be pulling accurate swabs!) and the horribly contorted state the bird was in gave every indication that it was NOT quick and painless. The only time I have ever used cold to euthanize was when I got a baby turtle that was so horribly mangled that it was a crushed mess. Rather than try to pull its head out to get to the base of its neck and cause it more pain I submerged it in an ice bath and the sudden shock of temp changes literally killed him instantly. I learner that from a visiting wildlife biologist at one of our clinics. This little turtle probably weighed 70 grams, though. The short of it is that freezing fish is not a desirable means of euthanization. There is also the fact that they can't breathe adequately adding to the pain of cellular destruction.
 
#17 ·
I don't think allowing a fish to slowly freeze, like going slowly from 78 degrees F to 30 over the course of a few hours is very humane because the fish's blood vessels explode. However, in my experience quickly removing a tropical fish from it's warm water and dropping it into ice water (literally, more ice than water) is humane. I once euthanized an ailing betta fish this way and in literally two seconds he had died. He jerked once, gasped, and then he was still. Still, just in case he was just in shock, I netted the unmoving body and thwacked it against the table. I'm not sure whether this would instantly kill goldfishes or other hardy fish however.
 
#19 ·
Fish, in water with rapidly falling temp. is hardly the same as putting a live bird in a freezer. i don't advocate tossing a fish into a freezer to flop around and freeze solid to the side of the Dove Bars.

I got the to the early stages of hyperthermia about 10 years ago. I got soaked while Elk hunting at 11K ft. I managed to keep my wits and hike just over a mile to camp. When I stumbled in I was shivering, exhaustion and starting to get confused. Fortunately, my friends we in camp to help. Dry cloths, warm water to sip, and I'm here today to take about it. I can honestly say I had no feeling of pain. I was/am experience enough to have know to force myself to stay calm & focused.
 
#22 ·
This.

In 2004 I fell in a lake while (foolishly) ice fishing in November. The water was about 38 degrees(there is the foolish part...). It took my friends about 4 minutes to get me out of the water. It was another 4-5 before we got to shore, another minute or two of fumbling to strip naked and get in a truck with the heat on and dry blankets. It was about 10 minutes to the hospital and my core temp was 94 degrees--still hypothermic despite 10 minutes of active warming.

The only point I experienced pain was during warming. The shock of falling in the water and the near drowning experience scared the bejesus out of me, but it didn't hurt. As a matter of fact, after being pulled from the water, I remember basically none of it. I'm sure my recollection of being in the water is abbreviated. My brain was both hypoxic and hypothermic, so you're not really able to comprehend anything, even basic things like pain and temp.

I'm not advocating this method of euthanasia, but I think people have general outrage to things without generally understanding all of the science around it.
 
#21 ·
It seems that there isn't really going to be any consensus here about freezing being good or bad, but here are some alternative methods I have heard of.

Decapitation. Very quick if the fish is big enough to get a reliable grip on. Post decapitation it is necessary to somehow destroy the brain so that the head does not stay conscious in what I can only imagine as being what seams like hellish eternity, although probably only a few minutes.

Gassing. I've read that if you put the fish in a container with water and add an alka-seltzer tab or two the CO2 will knock them out and suffocate them. I'm not sure how quick and painless this is though. Doesn't alka-seltzer have lemon flavor? Would that burn the gills?

There are also instructions out there on using clove oil and alcohol. Some seem to think these are the best methods.

I always thought there must be some way to quickly do it with an electric charge, but that would bring same serious issues regarding safety into question.
 
#25 ·
The most recent consensus is that freezing is very painful and inhumane. Ice crystals form in the blood/cells.
The mind is the last to go (was reading this on reptiles) and they are conscious of what is happening while the rest of the body shuts down first. Im not entirely sure the difference with humans freezing and ectotherms, but maybe someone can find some sciencey articles on that.

Want to put a fish down?
Clove oil is an easy way to put a fish to sleep. Or quick physical trauma- get the brain/spine severed, crushed, destroyed using force. Its downright 'dirty' so it is easier for people to put a fish in a freezer and not worry about it vs using your own hands to end a life right there.
 
#26 ·
on a related subject (if the OP wants me to make another thread i can), does anybody know how painless suffocation by baking soda is?

i think it's related to gassing with alka-seltzer, but the last time i was at a friend's house we felt it necessary to put down one of her EXTREMELY sick fish (he was under a piece of driftwood with his tail down, shaking and he'd been that way for days) and we weren't sure how, so we googled methods and we found that you can put a whole lot of baking soda in water, mix, and drop the fish in and they'll die...

it seemed to pretty instantly take away his ability to swim, he floated to the top of the jar in seconds, and he stopped moving his body but his gills continued to move, which made me wonder if he wasn't in pain while alive? i'm not sure if there's any way to know what moment a fish stops feeling pain, but has anyone else used this method? what were your experiences?
 
#27 ·
no prob with the above staying in here, its all welcome.

my thoughts with the freezer are different to some on here, people say ripping apart etc but are they not basing that on a human body? th temperature range a human can suvive is very wide , say 60 celcius swing.

tropical fish have a fairly narrow livable temperature range so to go from 26-28c /82 f to -20C / -4F in a few seconds would result in a very quick bodily shut down i would say.

of course brainal injury would be the quickest but thats a tad difficult with a neon unless you bash it with a meat hammer !
 
#28 ·
+1 for clove oil...it is absorbed thru the fish's gills and the fish slowly goes to sleep, then you can freeze the body to make sure life has gone :(

I had to do this for one of my Bettas...it swam around in circles in the container for a few minutes then just floated on its side and I then froze it, and put it out in the trash.

You can use clove oil to anesthetize fish for surgery too, its the same when you have a toothache, rub clove oil on it and wham no feeling whatsoever (course the whole area goes numb too, but when its a toothache who cares :)) The fish just goes numb and its brain slowly shuts down.
 
#34 ·
I am new to this forum but not new to pets or the use of common sense.
If you claim to be an aquarist of at least moderate experience you should probably also possess enough common sense to see that there is no empirical evidence that putting a living fish in a freezer is 'humane' and that the fish does not suffer from this death. It is however, quite evident that decapitating a fish is the most efficient way to give it a quick death.
 
#39 ·
....
If you claim to be an aquarist of at least moderate experience you should probably also possess enough common sense to see that there is no empirical evidence that putting a living fish in a freezer is 'humane' and that the fish does not suffer from this death....
I would offer a reasonable person would try to educate themselves on the physiological effects of any method before adopting it as a solution or criticizing others for their choice. I do understand this can be a disturbing topic for the more emotional members of the community.

BTW - Welcome to the forum
 
#35 ·
Alright guys, now I have to ask, because all you have discussed begs the question, why does it matter?

If you're going to kill the fish anyways, why does it matter how you kill the fish? Because it feels less pain? Because you feel less pain?

You need to step back and realize that there are plenty more fish in the sea, and that's that is all it is, a fish you took from the sea. Sometimes when you love something, you have to just hit it with a hammer.
 
#40 ·
Because current research shows that fish feel pain, and you show compassion by being humane in killing an animal. Of course, some people wont care, to them it is just a fish. But to some, they are beloved pets just like any dog or cat. Would you put your dog in a freezer to humanely put it to sleep?
 
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