Rodent bait causes other animals to suffer needlessly

I lost a Welsh corgi who got into rat poison. We got her to the vet within 24 hours but he said the vitamin k was given too late to reverse it.

Whatever you do don’t toss the freaking poison straight on the floor or outside on the ground where anything and anyone can come in contact with it!

I absolutely agree! It’s possible it has been reformulated since my loss but who is willing to take the risk?

d-dbriefoct2002.pdf (226.9 KB)

Welcome to the forum, and dang! That is quite a story.

Many places are attempting to further restrict anticoagulant poisons. The one my mom keeps leaving out is a nerve toxin. There is no antidote if something does ingest too much besides inducing vomiting and trying to use activated charcoal to absorb it but it takes a whole lot more to impact other animals.

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I’m trying this approach to control pine voles in my nursery - has anyone done something similar? This was shared with me by a grape-grower who had their entire planting decimated by voles, and this seemed to work. I’m planning to place traps outside of tunnel entrances, perhaps with a large box covering them to prevent any other animals to get to the bait.

You can eliminate ground squirrels and rodents without harmful poisons by using a bait of one
part plaster of paris to three parts raw oatmeal and placing about a cup at a time in the upright
tube of this simple Rodent Bait Module built out of PVC pipe. The mixture constipates and kills
squirrels and other rodents, but has no harmful effect on predators that may eat the dead animals.
The traps have been used for years by wildlife biologists in California and other areas. Some
designs use an upside down T made out of 4-in. PVC. This design includes a 30-degree angle
fitting to keep the bait inside and to protect non-target species. The trap can be buried in the
ground (or in feed lots or feed storage areas for other rodents) with only the openings exposed.
Caps can be screwed on the ends when rain is expected to protect the bait from getting wet.

As I mentioned, we will use oats and plaster of Paris.

  1.   First we will fill the bait stations with oats ONLY.
  2.   Second after a week a good feeding, we will add the plaster.
  3.   The stations will be in PVC in shape of a upside down T with a cap on top so that

the bait remains dry, is only accessible to ground squirrels and will be easy to monitor
for bait depletion.
We will use a total of 8 stations in our fields.

  1. Add oatmeal, plaster and sugar or chocolate powder as 1:1:1/2 ratio into a bowl
    and mix it well.
  2. Then, place 1 or 2 cups per bait station.
  3. Check level of bait daily.
  4. Refill station as necessary.

Years ago, I used - and advocated for - peanut butter/Plaster of Paris ‘bonbons’ as a tree rat ‘poison’. I had placed those little pb/PoP balls where they were readily accessible to squirrels. Pilfering seemed to abate significantly, but I never saw any dead or distressed critters.

Seems like someone in this group live-trapped a squirrel and fed it pb/PoP exclusively for a couple of weeks…with no ill effects noted. Kinda burst my bubble…

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Yeah, that was me who fed a squirrel Plaster of Paris mixed with peanut butter. It was 50/50 mix.

The experiment was rightly criticized for only having a sample size of one (and one control squirrel I fed acorns) but it was more than anyone else had done. The squirrel seemed to have no problem digesting the plaster of Paris. It did slowly turn the squirrel’s poop white as the plaster of Paris worked through his digestive tract, but never killed it. I think I fed it the Plaster of Paris concoction for about 2 weeks and gave up. I kept both squirrels in two large separate dog cages. I took pictures and recorded the whole thing on internet. It’s been over 10 years ago.

I did the experiment because there were a lot of people using the plaster of Paris for squirrel control, but no one could confirm that they saw any dead squirrels, from the bait (as Lucky mentioned above). So there was a sort of debate among backyard fruit growers whether the Plaster of Paris worked or not.

There were some people reporting on fruit forums that were feeding purchased rat bait (I don’t know if they were using anticoagulants or bromethalin) to squirrels and they were seeing dead squirrels, so I, and others, wondered why no one was seeing dead squirrels from Plaster of Paris. I tried to offer some small amount of testing to have any any idea if it worked or not.

It is possible to die from bowel/stomach obstructions. Below is a case study where a woman tried to commit suicide by eating 450g (1 lb.) of straight/undiluted Plaster of Paris. It caused a digestive blockage. I’m of course not a physician, but I would guess she would have most certainly died had the blockage not been surgically removed. Probably a very long painful death. I used to be a pig farmer, and pigs are sometimes born with a “blind anus”, meaning they have no anus. They will live a surprising amount of time before they eventually bloat up and die. Of course once these pigs are identified, we would euthanize them to spare them the painful death.

It’s possible that my squirrel sample of one didn’t eat enough at one time, or that mixing with oats would somehow be more prone to cause a blockage, but I’d be skeptical that it caused a blockage, unless there was also visual confirmation of dead squirrels, preferably with some postmortem examinations of the stomachs to confirm blockage.

I know personally of one other backyard orchardist who had so many squirrels pilfering his fruits, he was getting no fruit from his fruit trees. He put out zinc phosphide bait and said he saw dead squirrels everywhere the next day His experience matches others that I had read on the internet. Namely that known lethal bait results in a visual confirmation of dead squirrels.

Still it’s possible Plaster of Paris and oats kills the squirrels so slowly from blockage, that they run away to die? But, I would have to see some controlled experimental confirmation (on a large sample size) before I’d believe it. Such a large sample size would be beyond my resources (or interest) so I won’t be doing any more Plaster of Paris experiments on rodents.


A few years ago we had a late freeze and we kept on finding dead squirrels in our yard. We found out that an unexpected frost can end up killing them as they cannot retrace their steps and that squirrels are very territorial. At first we thought the squirrels chasing each other was them playing but we learned that was them chasing the other squirrel out of its territory. Since they are territorial new ones often just replace the old ones kind of like rulers taking over kingdoms. We use the dehydrating mouse traps for things like squirrels and bunnies but try to not put them in open areas.

I’ve tried a lot of vole deterrents, traps, and other, to no avail.

We’ve had some success with this thing

I’ve also read that dry ice can work.

Dry ice works; if you happen to have a CO2 canister from home brewing or welding that works too.

Plaster of paris works on small numbers of rodents attracted to the chosen bait if refreshed often enough and they don’t have plenty else to eat that will counter the amount of plaster. Especially watery or stool softening foods, which fruit generally counts as. If they prefer to eat a ton of currently growing fruit or lots of new green shoots over eating the plaster it isn’t likely to work well. If mostly all they have is high fiber older plant matter, seeds, nuts, some harvested grains, etc… and reason to eat enough plaster bait it will kill some. Whether it kills them fast enough to eliminate the problem depends on the starting population, any sources for more rodents nearby, and species.

When we used it for the mass of house and shed dwelling non-native house mice it only slightly slowed them down. We started putting it out in late fall with the only food on our property being a few apple trees and berry plants that the birds had finished cleaning up whatever we hadn’t picked. The mice were coming inside due to the lack of enough food anywhere else before it got all that cold and we only noticed a few signs of them then. Despite being the only food source on our property though it did not work for such a rapidly reproducing species of rodent with no predators around. I think I went through 3 boxes of plaster with some mixed with peanut butter, some mixed with grains and other ideas people had that I don’t remember all of before giving up on it completely. It’s not like they weren’t eating it. They were just multiplying fast enough on I have no idea what for other foods that it didn’t kill more adults than the offspring they managed to raise.

For voles that both reproduce and move slower I’ve never had to do much except not chase off every possible predator and let the dogs sniff around where they are hiding. It worked on 42 and 80 acre farms. The latter having large trellises of hundred year old grapevines, blackberry bushes gone wild in a 10’ wide by about 200-300’ long area between where the grass was mowed and a creek bed, and lots of older, heavily producing nut trees. Rodents except invasive rat species were still easy to control with predators.

The dogs also completely stripped our new yard in a small town of all the native voles and shrews in the first summer all by themselves after the previous owners spent years trying to deter or poison the rodents without managing to get rid of them. The amount of rodent digging had them thinking there was a mole problem but there were no large mounds in the middle of the yard. Dozens of dead shrews and voles kept appearing though with increasingly fewer being younger ones.

For places you can let them roam chickens have to be the most efficient, least damaging, small rodent control (as well as some insect pests) I’ve ever had. My husband who grew up in town found it quite surprising the first time I told him to just go empty the live trap in the middle of the chicken flock. The whole flock went nuts fighting to get the mice and gulped them right down without a single one getting away. Very few things smaller than a rat will survive even a flock of most bantams left to wander the area. Japanese bantams were designed to be essentially living garden decorations so disturb soil and plants far less than most poultry, are not easily startled, and make very little noise. Aside from being the only ones I let around new plants and herb garden beds I even had a trio with a rooster in the spare bedroom on the other side of the wall from where I slept for some fresh winter eggs with hardly enough noise to let anyone know they were there. Too bad even the tiny bantam breeds aren’t allowed in any city limits I’ve lived in since then.


I’m curious, did you ever see large numbers of bodies of dead rodents immediately after setting out the Plaster of Paris (that you were certain were not caused by dogs or cats?)

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There were some dead mice in the small plastic containers I used to contain the plaster so the dogs were less likely to accomplish eating any. I cut holes a mouse would easily fit through in the side and there is no way they simply got stuck. I don’t remember how many were in the bait containers but when refilling them I’d have to dump some bodies. There were also some dead in the basement and occasional smell in some rooms from likely dead mice in walls or between floors. The phorid flies that appeared most often get established as indoor pests due to dead animals under homes or in attics.

Nearly all dead mice found prior to putting out rodenticide were plaster baits or natural causes besides predation. I don’t know how many that was partially because the mice soon seemed endless in numbers. More than should have if we did nothing definitely died but at a slower rate than they made more or we gained more from where ever they started coming from.

Our cats at that time were useless. They accomplished one dead mouse and I’m not sure they killed it. The one we still have we bottle raised and the other cat at the time had been indoor only from 3 months old. While my family had a rat terrier mix on the farm my dogs have all been 50lbs minimum so in a house they can’t get rodents before they dash under furniture or behind things. Probably only 3-5 mice died to dogs indoors. If you want a yard or field stripped of rodents and don’t care about the holes that dogs up to 120lbs can dig they will spend all day and night obsessing about the rodents until they get to them. Indoors they just knock things over and stare under furniture insisting you get the mouse out for them.


Thank you. This is the first time I’ve ever heard anyone see dead rodents from Plaster of Paris.

Would you mind giving the formula of proportion of food and Plaster of Paris?

If Plaster of Paris truly kills rodents, then that would be quite helpful for me. We have voles that can be very damaging at our orchard we poison with zinc phosphide. It’s expensive and can be dangerous to handle. I would much rather use a safer and cheaper product, if it works. Baiting occurs during the winter, so the voles have no source of fruit or green vegetation, only seeds.

Even though I said I’d never do any more testing, I may try to test it first to see if it works, so I’m not putting out a benign product.

I have a friend who is a mouse farmer (yes there is such a thing). As I recall, he raises over 1000 mice per week, for pet food stores. I may try to get him to run an experiment and feed a few mice the Plaster of Paris concoction. That’s why I need the formula for exact ratio of food to Plaster of Paris. I know he’s not going to want to tinker around and do the experiment over and over to find what works. Since you already have the secret sauce, I just need to know the formula.

If Plaster of Paris really works, it would be an enormous breakthrough, not only for me, but for others as well.


I need it to work on fox squirrels. They’re hell on my plums and pears and even apples.

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I met someone years ago that was using Alka-Seltzer mixed with peanut butter to kill mice in a cabin.
Claimed that it worked well.
Since , I have seen claims on the internet,that Baking soda mixed with some thing edible, like oatmeal ?flour ? Peanut butter, etc… would kill mice.
The claim is that small rodents can’t burp ? / or fart.
Baking soda supposedly creates gas in their intestines.

The ingredients in Alka-Seltzer that creates the very active effervescence are “” baking soda and citric acid.””
The ratio in alkaline-seltzer is roughly 2parts baking soda / 1 part citric acid
( Both of which are dirt cheep. )

If the above is true ?
I visualize a experiment, , !
Something like a small pack of flat corn tortillas
With alternating layers of baking soda citric acid and peanut butter.
Such that the ingredients remain separate until chewed .
Could be cut into strips , chunks , rolled up ?
Like pieces of a layer cake .
Think ? …… vinegar / baking soda volcanos inside of mice / voles
May need earplugs ? Safety glasses? For heavy infestations :face_vomiting:

Anyhow , something I hope to try,
need some volunteer mice.
Should be pet safe , as long as can burp ,/ , fart ?
( , But you may want to kill them ? .)

@Olpea maybe a good experiment for your mouse farmer friend ?

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Then obviously Mentos and diet soda are the answer to my squirrel problem.


Sorry if this was already shared. This video shows a super effective and simple approach but also gives me the creeps

. Best Mouse Traps | The most effective simple homemade mouse trap | Traps with plastic buckets - YouTube


I used to have a Jack Russell mix who was heck on the rats. Then she discovered the joys of eating grubs. And now is a porky/ slow sausage roll of a dog. We wanted Chiweenies again. Superb ratters. But we do not think they would not get along with our LSG dogs. The LSG’s kill everything else bigger then a rat. We also shoot clear problem animals that seem sick. We see a fair amount of psuedo-rabies here in wild animals.

Turned down a beautiful Caucasian Shepard dog. He flat made our big race Pyrenees look puny. But those can be quite hard to rehome. Had to be around 200 pounds. Our big girls run about 150-160.

Much like Anatolians and Kangel’s, Caucasians can be scary animals. A bit too bullheaded and determined to protect too remain under control.

Creeps, no, funny, yes. Johnny dived right in, why not me.