# What's the most humane way of killing mice? **URL:** \ **Category:** Factual Questions\ **Created:** [March 22, 2012, 10:54am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481 "2012-03-22T10:54:56Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![jackdavinci](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackdavinci/32/3259_2.png) [@jackdavinci](https://boards.straightdope.com/u/jackdavinci)\ **Post date:** [March 22, 2012, 6:48pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/41 "2012-03-22T18:48:16Z")
> [@Alessan](#): > > But mice have evolved to live in human houses for the past 5,000 years. Humanity is their natural environment, not nature. Is there a cite for this? How do the mice get into the house in the first place if they can’t abide nature? ---
**Author:** ![Inigo\_Montoya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/inigo_montoya/32/124_2.png) [@Inigo\_Montoya](https://boards.straightdope.com/u/Inigo_Montoya)\ **Post date:** [March 22, 2012, 7:16pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/42 "2012-03-22T19:16:03Z")
> [@jackdavinci](#): > > Is there a cite for this? How do the mice get into the house in the first place if they can’t abide nature? Lotsa critters rely on learned behavior at least as much as instinct–it’s an extraordinarily useful ability because it allows an organism to make rapid changes in behavior to adapt to immediate changes in resources. If you wait for evolution to change your instincts, your species is toast within a generation of things change rapidly enough. Mice figured out humans are messy and leave lots of food lying around and they exploited that fact. Or to put it another way, how well do you reckon humans would do if, tomorrow, they were plonked down on earth 50,000 years ago with no houses, WalMarts or even calendars?That’s essentially what you’d be doing to a mouse if you let it go in the woods. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [March 22, 2012, 7:17pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/43 "2012-03-22T19:17:51Z")
Oh fer chrissakes. Y’all are being a bit literal here. In my house (wait, in my house are two cats, so lets talk about my house a year ago) there are no natural predators. The temperature and humidity are controlled for comfort. Food is abundant (pantry, crumbs under the fridge, dirty dishes left out overnight etc.) and water easy to find (faucets drip.) There are plenty of spaces in the back of cupboards which aren’t opened regularly to make a nest, and plenty of soft fluffy stuff like Kleenex and socks for nesting material. What’s not to love? It’s like mousey heaven. Surely you can see that a mouse living here (before cats) would have a comparatively sweet life compared to the mouse living outside my house in the alley. There are cats out there. And dogs, and it’s cold a lot, and while food and water are still plentiful, there are many other mice fighting for it - not to mention squirrels and racoons and opossums. There are cars to dodge, kids on bicycles to avoid. There are more mice out there, too, and while perhaps mice have some social tendancies that nurtures, that also means more mice to spread illnesses among one another and more fighting for turf or mate. Kicking a mouse out doesn’t mean he’s going to suffer and die in the next 12 hours, but it does increase the chances that he’s going to suffer and die more and sooner than a mouse snuggled in next to my cookie cutters in warmth and abundance. ---
**Author:** ![KCB615](https://avatars.discourse-cdn.com/v4/letter/k/ea666f/32.png) [@KCB615](https://boards.straightdope.com/u/KCB615)\ **Post date:** [March 22, 2012, 7:36pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/44 "2012-03-22T19:36:54Z")
Easiest on me? Drowning. I’ve been using a 5-gallon plastic bucket with an empty can on an axle inside, with a wooden ramp leading to the can. Back end of the can is covered in peanut butter. Bottom of the bucket has about a gallon of antifreeze. Critter goes up the ramp, and jumps onto the can to get the peanut butter. Can rotates, critter falls off into the antifreeze, and swims in circles until he can’t swim any longer. There are a multitude of ways to make it, [Google is your friend](http://www.google.com/#hl=en&sclient=psy-ab&q=5%20gallon%20bucket%20mouse%20trap&oq=5%20gallon%20bucket%20&aq=1&aqi=g4&aql=1&gs_l=hp.11.1.0l4.936l3198l0l4805l16l7l0l9l9l1l281l1187l1j4j2l15l0.cfis.1.&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=9487830796264a14&biw=1440&bih=772&pf=p&pdl=300)for designs. I have used that trap for a couple of years now. If there is a mouse in the attic, I can generally get him within a few hours. The mouse problem in my shed is gone. I emptied the trap several months ago with over 40 (deceased/marinated) mice in it. Wipe off the can, fish the mice out of the antifreeze with a basket strainer, apply new peanut butter, and its good to go for another few months. If you use antifreeze, the mice don’t even smell. Don’t let animals you like go near it, though. Most certainly not good eats for them. I’d rather have them floating in antifreeze than gnawing on the wiring harness in my lawnmower. ---
**Author:** ![wheresmymind](https://avatars.discourse-cdn.com/v4/letter/w/91b2a8/32.png) [@wheresmymind](https://boards.straightdope.com/u/wheresmymind)\ **Post date:** [March 22, 2012, 7:38pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/45 "2012-03-22T19:38:45Z")
> [@WhyNot](#): > > Jeezus. I with humans would stop being so selfish and get over our own squeamishness. Humane for who? The mouse? Is that why we humanely kill people who need killing by leaving them out in a snowbank? Sure, eventually you fall asleep and die, so I suppose you could consider the death itself technically humane, but the minutes or hours of torturous cold and frostbite before that, where you feel your toes stabbing with burning pain, and then you don’t feel them at all, and the air is scorching your lungs with its cold fingers and you’re coldcoldcold bone cold and this sucks and why can’t you just get warm? > > I mean, I’ve never frozen to death, but I’ve spent some cold nights in a tent, and it’s pretty damn torturous. The rationale for this method that I’ve heard is that it’s supposed to trigger hibernation, which _would_ presumably be painless, if it were true. Unfortunately I think you’d have to slowly decrease the temperature, reduce the amount of daylight, and ration food over a period of weeks to achieve this. Somewhat related off-topic anecdote: In undergrad a professor of mine used bats in his research. He went through a lot of them but they’re messy and difficult to care for. To avoid caring for hundreds of bats all year, he kept most of them in hibernation in a styrofoam cooler in his fridge, “waking up” only what he needed at any given time. He said they’d keep for ~6 months or more if he properly prepared them. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [March 22, 2012, 7:58pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/46 "2012-03-22T19:58:05Z")
unless you provide all the food and water then mice are outdoor creatures. in a cold winter climate you might find them only in your home (even big city) when it starts getting cold outside. they are looking to nest in the warmth and may bring seeds in for a cache. in the country they might do likewise in unheated buildings. they will tear up a lot of material to make food cache and nest areas. ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [March 22, 2012, 8:12pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/47 "2012-03-22T20:12:51Z")
Kill them softly. With your song. ---
**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\ **Post date:** [March 22, 2012, 8:56pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/48 "2012-03-22T20:56:40Z")
> [@araminty](#): > > Cite? I believe the large rodent providers usually gas their rodents with carbon dioxide prior to being frozen for storage/shipping. Just an acquaintance of mine who does this as a side-line and told me that live freezing is the standard way. Perhaps he was wrong, or he was talking only about mom-and-pop rodent killers such as himself. ---
**Author:** ![Biffy\_the\_Elephant\_Shrew](https://avatars.discourse-cdn.com/v4/letter/b/e47c2d/32.png) [@Biffy\_the\_Elephant\_Shrew](https://boards.straightdope.com/u/Biffy_the_Elephant_Shrew)\ **Post date:** [March 22, 2012, 10:02pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/49 "2012-03-22T22:02:37Z")
> [@Scumpup](#): > > I like using a humorously over-sized wooden mallet. I think your [truck](http://www.flickr.com/photos/batgrl/5394257481/) was parked next door to me yesterday. ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [March 22, 2012, 10:56pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/50 "2012-03-22T22:56:54Z")
My dad used to work in the food supply department for a large zoo- the feeder mice (and rats) there were despatched by picking up by the base of the tail, and smacking them hard on the floor or a concrete slab. That was the fastest, most humane way they found in 20 years. Incidently, he did tell me they tried the car exhaust method once, and several hours later, everything was still alive, just grubby. Obviously, that’s not going to work for a wild mouse unless you too have scary reflexes- I really think the snap traps are the best option overall. I know freezing is no longer recommended as a humane way of killing ornamental fish, as they apparently chill so fast the outer blood vessels can burst, from the formation of ice crystals, before brain function ceases; I’m not sure if this would be the case for mice too. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [March 22, 2012, 11:32pm UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/51 "2012-03-22T23:32:37Z")
> [@](#): > > What’s the most humane way of killing mice? Old age. ---
**Author:** ![GavinB](https://avatars.discourse-cdn.com/v4/letter/g/ad7895/32.png) [@GavinB](https://boards.straightdope.com/u/GavinB)\ **Post date:** [March 23, 2012, 2:18am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/52 "2012-03-23T02:18:58Z")
Freezing mice to death? What the hell? No, that is inhumane… whoever said it is humane is an idiot. Take a look at this [link](http://www.aussiepythons.com/forum/herp-help-38/freeze-rats-humane-way-30144/) and see what snake owners think about such a method. As mentioned already, cervical dislocation is the most humane way if you know how to do it. But the main method is using a CO2 chamber, where the animal pretty much dies in its sleep. Freezing a mammal to death is completely inhumane and disgusting - and what the hell does body surface ratio have anything to do with how long something dies in a freezer?? It’d still be affected in much the same way a human of any size would - yeah, I’m sure frostbite and having ice crystals form in cells and burst is plenty of fun. Really now… for those who advocate freezing and torture the poor animals by doing this, go outside in a location where it is -20C and stand naked there for 10 mins. Then come back and tell me how “humane” that was for you. Incredible there are people out there who think such a method is humane, I’d assume people here are brighter or less ignorant than that. ---
**Author:** ![chacoguy](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@chacoguy](https://boards.straightdope.com/u/chacoguy)\ **Post date:** [March 23, 2012, 2:34am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/53 "2012-03-23T02:34:38Z")
I’d say gently overdose them on heroin. ---
**Author:** ![brainstall](https://avatars.discourse-cdn.com/v4/letter/b/35a633/32.png) [@brainstall](https://boards.straightdope.com/u/brainstall)\ **Post date:** [March 23, 2012, 2:40am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/54 "2012-03-23T02:40:11Z")
I think mice are cute and I do not like killing them, but when they invade my pantry, I bring out the snap traps. I hate doing it, but hate having mouse poop everywhere and finding food ruined because I didn’t put it in a mouse proof container more. So I suck it up and bait the trap with peanut butter. So far, I’ve only had one not dead mouse (must have tripped the trap by running over it, rather than going for the bait) and lots of very dead ones. I also hate having to empty the traps and if it’s the least bit icky, I toss the whole thing, dead mouse and all. They’re cheap enough to not bother me to toss one, though most times, I can release the body and rebait it and put it back in the pantry. I don’t know how anyone could use glue traps. I don’t like it, but I can deal with a quick kill for mice. I can’t deal with torturing them to death. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 23, 2012, 2:52am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/55 "2012-03-23T02:52:36Z")
> [@GavinB](#): > > But the main method is using a CO2 chamber, where the animal pretty much dies in its sleep. I don’t understand why this is a common meme, i.e. that CO2 just makes you go to sleep. Here are a few experiments for you to try. Experiment #1: hold your breath. Keep holding it. Feel that burning sensation in your lungs, the sensation that makes you want to gasp for air? That’s due to relatively low concentrations of CO2 in your lungs. Experiment #2: Take a 2-liter bottle of carbonated soda. Open it, pour a couple of glasses of soda. Cap it off. Shake it, or else let it sit for a bit, so that it reaches equilibrium again (resulting in a high concentration of CO2 in the upper part of the bottle.). Now uncap the bottle, exhale, seal your lips on the bottle, and inhale; you may have to squeeze the bottle a bit to collapse it and help the gas into your lungs. Feel that extremely strong, painful burning sensation in your lungs? That’s a significantly higher concentration of CO2. Experiment #3: Get a piece of dry ice, drop it in a 2-quart zip-loc bag, squeeze out all the excess air, and zip it shut. The dry ice will sublimate, filling the bag with almost pure CO2. Keep an eye on it, because you don’t want to burst the bag. When it’s fairly full, unseal a short portion of the top of the bag, exhale, put your lips on the bag, and inhale deeply. Be advised that _this fucking hurts_ (yes, I’ve done this). You’ll be in agony, probably unable to inhale a complete breath. Now imagine you’re a rodent, and you’re in a pure CO2 environment; nothing to breathe but CO2. Every breath is agony until you pass out, and that’s gonna take a bit; asyphxyiation due to oxygen displacement doesn’t happen immediately. Carbon _mon_oxide results in painless and rapid death in high concentrations, but of course that’s dangerous for the person involved in killing the animals. > [@](#): > > Freezing a mammal to death is completely inhumane and disgusting - and what the hell does body surface ratio have anything to do with how long something dies in a freezer?? Basic physics. Heat capacity is proportional to volume; both are proportional to the cube of the characteristic length of the animal. Cooling rate is proportional to surface area; both are proportional to the square of the characteristic length of the animal. So if you have a small animal exposed to cold, it tends to cool off very quickly. ---
**Author:** ![jackdavinci](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackdavinci/32/3259_2.png) [@jackdavinci](https://boards.straightdope.com/u/jackdavinci)\ **Post date:** [March 23, 2012, 5:16am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/56 "2012-03-23T05:16:41Z")
Given the lack of cites or even a coherent argument I’m guessing the “house mice have evolved to be stupid if driven a block away” story is some kind of old wives tale. Just use a humane trap and deposit the mice somewhere with lots of leaves or other vaguely reasonable shelter. They’ll be fine. ---
**Author:** ![Dereknocue67](https://avatars.discourse-cdn.com/v4/letter/d/6de8d8/32.png) [@Dereknocue67](https://boards.straightdope.com/u/Dereknocue67)\ **Post date:** [March 23, 2012, 7:25am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/57 "2012-03-23T07:25:14Z")
I use a live trap and then take them to my neighbor’s house and he talks to them until they are bored to death. I have experienced it but it isn’t painless. ---
**Author:** ![GavinB](https://avatars.discourse-cdn.com/v4/letter/g/ad7895/32.png) [@GavinB](https://boards.straightdope.com/u/GavinB)\ **Post date:** [March 23, 2012, 9:11am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/58 "2012-03-23T09:11:58Z")
> [@Machine\_Elf](#): > > I don’t understand why this is a common meme, i.e. that CO2 just makes you go to sleep. > > \ Do you realise that none of your analogies are valid because the CO2 used to gas mice is introduced _slowly_ and in certain volumes? It’s nothing like what you described. CO2 is approved by vets and lab technicians the world over, it is certainly one of the most humane ways to go. Far more better than freezing to death. Of course an instant lack of oxygen (ie. choking) would be panic inducing, but that’s not how the animals are getting killed. > [@](#): > > Basic physics. Heat capacity is proportional to volume; both are proportional to the cube of the characteristic length of the animal. Cooling rate is proportional to surface area; both are proportional to the square of the characteristic length of the animal. So if you have a small animal exposed to cold, it tends to cool off very quickly. Yet it still feels the pain of having frostbite and ice crystals burst from their cells. I find it funny how you’re trying to put a cold, clinical slant on this when you’re completely neglecting the welfare of the animal. Freezing a mouse to death isn’t fast, it isn’t instant and it certainly is not painless. > [@brainstall](#): > > I don’t know how anyone could use glue traps. I don’t like it, but I can deal with a quick kill for mice. I can’t deal with torturing them to death. Glue traps should be illegal. Barbaric things, and the people who use them are barbaric, unfeeling people too. Torture is unacceptable, but I suppose with so many heartless morons around, I guess it’s acceptable for them. ---
**Author:** ![GavinB](https://avatars.discourse-cdn.com/v4/letter/g/ad7895/32.png) [@GavinB](https://boards.straightdope.com/u/GavinB)\ **Post date:** [March 23, 2012, 9:19am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/59 "2012-03-23T09:19:28Z")
> [@Little\_Nemo](#): > > Another consideration is the post-death clean-up. A snap trap can be pretty messy. Sometimes the mouse will essentially explode. And a glue trap isn’t messy, especially when you have a live animal thrashing around in it, splashing it’s piss and poop everywhere, being no doubt bloody from ripping its skin off? Then there are those that might gnaw a leg off, crawl around with blood everywhere and die in an inconvenient spot. Snap traps are CLEANER in comparison. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [March 23, 2012, 9:23am UTC](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481/60 "2012-03-23T09:23:51Z")
> [@isaiahrobinson](#): > > I’m not too squeamish about the mouse dying, as long as it dies quickly and painlessly. A big rubber mallet is probably the thing, then. You’ll want a face shield, though. [Previous page](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481.md?page=2) [Next page](https://boards.straightdope.com/t/whats-the-most-humane-way-of-killing-mice/616481.md?page=4)