Rat Baits

Within the pest control industry, rat bait generally refers to the use of poisons to kill rats.

Toxic substances, often scented and flavored to appeal to the rodents are set out in traps or stations. The rats ingest the products and die—a process that can take up to a week to occur.

There are non-toxic rat baits as well, which are used primarily to lure the rat into a trap to be killed, or into a live capture trap from which the animal is later released.

Non-toxic rat baits

Rats are amazingly canny and cautious creatures with a powerful sense of smell and an acute sense of taste; baiting rats can be challenging in the extreme as a result of these characteristics. Rats are also adept at freeing easily portable types of food from snap traps without activating the mechanism. They avoid “new” objects in their environment and have been observed “testing” food sources by ingesting small amounts and waiting to see if they grow sick before eating more.

Non-toxic baits are generally used to lure rats into traps, be they the classic snap trap; other lethal types of traps or capture and release devices.

Because rats are scavengers by nature the most effective rat attractants are food baits; some of the most successful (depending on the species of rat) of these are:

Peanut butter: Whether creamy or chunky, the taste and smell of this childhood food favorite is irresistible to rats. Peanut butter has the added benefit of being difficult to remove from a trap, unlike a seed or cheese morsel which may be snatched and carried off to be eaten. The consistency of peanut butter when placed strategically in a trap forces the rat to stay at the bait to ingest it. Peanut butter is particularly efficacious when used in concert with snap-traps
Fruits and vegetables are particularly appealing to roof rats. Because of high rates of spoilage these baits must be changed out frequently, a rat will not approach or eat rotting or spoiled foods.

Meats and fish are attractive to the Norway rat, but if used must be swapped out frequently and not used in traps to be placed in locations unreachable by humans.

Seeds, particularly pumpkin seeds are known rat attractants but must be carefully placed as they are easy for the rats to snatch from the trap without activating the mechanism.

Dog food is usually irresistible to rats; dry foods may be liberated from traps, a dab of canned food must be changed out frequently to avoid spoilage. Canned food, like peanut butter is less portable and more likely to keep the rat eating in place.

Bacon is nearly as mouthwatering to rats as it is humans, whether offered alone or mixed into peanut butter, dog food or other bait mixtures.

There is some strategy involved when using food baits. It is more effective if a trap put out but is not set for several days while baited; this will accustom the rats to eating safely at the trap location reducing the incidence of “trap shyness”. Baited traps should be placed in or along the rat’s regular line of travel (detectable from droppings and urine stains); rats are cautious and will not break their normal routine to investigate even the most attractive baits.

The use of nesting materials as bait has also proven effective. Cotton balls dipped in vanilla extract are said to be particularly attractive to female rats; other soft materials work equally as well. The trick is securing the cloth, cotton ball or string to the trap in such a way that it will lure the animal in close enough to activate the mechanism and not just be snatched away.

The Middle Ground

1) Instant potato flakes set out along a rat trail with small bowl of water nearby is said to be a highly successful non-toxic way to eliminate rats. The theory is that the rats eat the dry potato flakes, which induces thirst; the rats will then drink the water. The potato flakes expand in the rat stomach, causing the stomach to rupture, killing the animal.There is anecdotal evidence that it is possible to kill rats without a trap or the use of poisons. While little authoritative information is available on the efficacy of these methods, many people swear by them. One of these methods (cement powder and corn-flour) has even been found on a rat bait website maintained by the government of Australia

2) Based on the same theory, a mixture of equal parts flour, sugar and baking soda placed on small disposable plates laced with peanut butter on the edges will cause a fatal buildup of carbon dioxide when the ingested mixture mixes with stomach fluids.

3) Another option is to mix corn-flour and dry cement powder and place the mixture in dishes along the rat paths. The effect is said to be the same as use of potato flakes, the mixture induces thirst and drinking additional water ensures the cement powder reacts becoming an indigestible mass in the stomach of the rat.

An issue with these non-toxic rat killers is the fact that the rat will not necessarily die where the bait has been placed, but may return to a nest or crawl away to die inside walls or other areas inaccessible to humans. The theory expressed in defense of this point is that the thirst inducing methods will drive the rats to find outside water sources, but there is no guarantee this will occur.

Poison Rat Baits

In times past one had only to pop down to the nearest general store and a choice of rat poisons was readily available to purchase. Arsenic, strychnine, thallium and cyanide have all been used at some point in history as rat poisons. As these substances became regulated and illegal to possess due to their great toxicity to humans, other presumably safer poisons have been introduced in their wake.


Anti-coagulants block the metabolic cycle of Vitamin K, an important factor in blood clot formation. When ingested in sufficient quantity, this class of rat bait induces massive internal hemorrhage and eventually, death.Anti-coagulant substances such as Warfarin (also known as Coumadin) were popular first generation rat baits. In fact, Warfarin was first developed in 1948 as a rat and mouse poison, only later was it found to be a helpful medication for humans prone to thrombosis and thromboembolism.

1) First generation anti-coagulant rat baits (Coumadin, Warfarin) are classed as chronic, meaning that the effects develop gradually and are dependent on several feedings to reach levels toxic to the rats. It can take a first generation anti-coagulant up to a week to kill the animal. In some respects this was considered an advantage, as rats were less likely to associate illness with feeding.

Although second generation anti-coagulants have been developed, first generation baits are still widely used. Some rat populations have developed resistance to this class of rat poison.

2) Second generation anti-coagulants were introduced to address some of the drawbacks of the first generation options. This class of rat bait is more toxic resulting in death occurring after a single dose rather than several sequential dosages. Because of their greater toxicity, smaller amounts of 2nd generation anti-coagulants are used in baiting the rats; and are particularly effective on rats which have developed resistance to first generations poisons like Warfarin.

Metal phosphides rat baits such as (zinc phosphide) are considered single dose effective and relatively fast acting alternatives to the anti-coagulant baits. Death of the animal occurs within 1-2 days.

The reaction of the phosphide to the acid in the stomach of the rat releases the highly toxic phosphine gas. Zinc phosphide based pellets exude a pungent odor similar to garlic which is attractive to the rats, but which tends to repel other mammals, making it safer for pets and non-target wildlife. Phosphides are not known to accumulate in the tissues of the dead rats, so the incidence of secondary poisoning is diminished.

Vitamin D rat baits specifically vitamin D2 (ergocalciferol) and Vitamin D3 (cholecalciferol), are another form of rodenticides found in rat baits. These two D family vitamins when ingested at toxic levels interfere with the balance between calcium and phosphates, resulting in a condition known as hypercalcemia.

Hypercalcemia kills by increasing absorption of calcium in foods with the end result being a calcification or mineralization of the blood vessels, kidneys, stomach and lungs. This in turn effects the myocardial action of the heart and results in hemorrhage and kidney failure. This class of rat baits need to be ingested only one time and can take anywhere from a couple of days to a week to kill the animal.

Secondary poisoning dangers

Nearly all of the toxic rat baits present a significant danger not only to family pets (and children if they get into the bait) but also to wildlife. Any species that preys upon rodents (owls, hawks) can and are often affected by poison rat baits through the consumption of affected rats. Federally protected species such as the Bald Eagle, the Spotted Owl and San Joaquin are particularly susceptible to population impact from these poisons.While it was claimed that these Vitamin D rodenticides reduced the possibility of secondary poisoning in pets and non-target animals, subsequent study has revealed this not to be the case. Dogs and cats are at particular risk when these rat baits are used; ingestion of a dead rat loaded with this class of rodenticidal bait will cause progressive renal failure in these animals.

If these baits are set out in areas accessible to deer, raccoons and squirrels, these relatively benign animals are prone to be exposed to and ingest these poisonous baits.

Rat bait poisons and the EPA

Due to the many dangers posed by toxic rat baits, the US Environmental Protection Agency (EPA) announced in 2008 that it was placing new restrictions on the sale and use of 10 rodenticidal rat baits. Scheduled to take effect in 2011, the new restrictions include the sale and distribution of the listed baits, minimum package sizes, use site restrictions, and making packaging tamper resistant.

The use of toxic rat baits has been controversial for many years. With the emergence of renewed environmental concerns among the general public, many pest control companies are forgoing the use of poisonous baits altogether and pledging themselves to “green” non-toxic rat control measures only.

20 thoughts on “Rat Baits”

  1. Thank you for this information. I think I’m going to chase my pest away with some strong orders. Ammonia. I’m thinking. Don’t want them dieing. In the walls. Lived here 4 years with no problem neighbors clean rd up bags of garbage. An now I have visitors. Had a chipmunk once he left on his own. Thanks again

    1. I think feeding bird seed to the wild birds has contributed to our now out of control rat problem. I’ve raised chickens for a many number of years with an occasional rat or mouse here or there and controlled it through snap traps. Now, with a hanging bird feeder in the yard, I have seen a rat running on the limbs of our fig tree at night, caught them face to face in the chicken house, and droppings every where in our barn storage area. They are smart…have only caught one juvenile rat in a snap trap baited with bird seed…I hot glue down the bird seed to make it harder for them to get it out of the trap. I’m going to try the instant potato flakes next. We have barn cats (that eat rats), a dog and my chickens so poisonous commercial bait is out of the question.

  2. So unfortunately we have a few rats in our garage living in there eating everything they can get theyre hands on
    we have caught 2 already and the others seem to have noticed rat traps arent friendly. we would love some help if you can get back to me at 209-606-0606

  3. I had rats in the attic 2 years back. It took ages get rid of them with poison. now they are back and will not go near the poison. What can I do.

    1. Hi i had a rat couple years ago cost over $2500 to replace water pipes it chewed (pipes actually have a soy product in them rat food) i have sealed the crawl space as good as possible. Now I have another rat. Norway/wharf rat. I looked on line found Motomco great product for killing and maintinance (QC supply 800-433-6340) also learned that BLUE CHEESE is lethal to rats (if you have a pet rat do not feed it blue cheese) I am in search of something i can throw under my house that willl kill the rat quickly. with out spending $50 or $10. Can you help me please ( I also purchased an electronic rat killer batteries purchased on amazon it works but hat wont go in it tilll they get use to seeing it for a while) I just need somthing to put under the house now. Thanks Lisa in Brookings OR

  4. Hi,

    I live with a stupid old man who likes feeding birds too much. Last year you would see the odd BIG rat but this year they are all over. I would say we have 40 plus rats in the garden. He will not stop and won’t let me kill the rats. I have mixed bird seed, cement and oats in a bait box out of view. Will this work? What else can I use to kill them without hurting the cats and dogs, (they watch the rats too). I am shocked at how clever the rats are, I saw them in the trees the other night. They will not fall for the bucket trap, I watched one pull the bottle towards the edge and eat the peanut butter.



  5. We have a rat problem in our back garden we have now put down 30 packets of pasta sachets poisen all have been taken over a period of 2 weeks last night we put down 10 packets and have all gone does this mean I have a very large problem ??? Should we put more down or do you think they are resistant to our poisen ??

  6. Have rats in a storage shed they won’t eat commercial bait such as tomcat. I’ve spent 100s on bait boxes and bait with no results. Doesn’t appear to be that many, but at nite they are coming out of shed and getting into are vehicles. I track them from shed in fresh snow. Tried a trap with peanut butter and only thing that happened was I lost my trap when took off with it. Put some fresh colostrum milk and anti-freeze in a pan and sprinkled powder sugar around it. They never came near it either. We are in Wisconsin if it makes any difference. Please help, thank you

  7. I have rats in my chicken house. I never see them in the daytime, but I can hear them. The chicken house is open all afternoon so that the chickens can free range, so plugging up holes is pointless. When I close the coop at night, sometimes I see the rats running across the joists and into the eaves. I have caught one with a Victor electronic trap, which electrocutes the rat. However, it never worked a second time. I have left numerous snap traps baited with peanut butter. Sometimes the bait is stolen (and it’s a large lump of peanut butter), and sometimes the trap is triggered, but no rat. I can’t use any poison because of the chickens and our other pets. I’m at my wits’ end. Any thoughts?

  8. JACK RUSELLS WILL KILL ANY AMOUNT OF RATS THERE BREED WAS FOR THAT REASON. There fast & kill the Rats Quikly. One Jack Russell kills over 100 rats in one minute if you check it out on YOUTUBE. See these dogs rating is unreal they rarely fail at there work & love it.

  9. My neighbor put ultra sound devices under his house and in garage now I have rats running everywhere never seen anything like it ive put down hundreds of dollars of poison and they are still out of control my ZEN garden is no longer ZEN HELP

  10. Rats chewed the cables on my outside washer multiple times. The repair man told me the best bait to kill rats and I will share it with you.

    He said “orange starburst candy” the other ones work well too but they can not resist the orange.

    Works every time and never spoils. Rats cant steal it unless they nuge the old style trap to set it off first. Drop a few near the trap to let them know it’s safe.

    I really wish they made the new Victor precision kill mouse trap in rat size. If you have a mouse problem use the new precision kill. They can push it and mess with it all they want and it won’t go off unless they press their face in a very clever trigger. Amazing trap but not big enough to kill a rat.

  11. I found that the best way to safely kill rats in our barn was to fill a large bucket with water and float cob (corn oats and barley) on top of the water. Rats climb into the bucket and can’t reach the bottom with their hind feet and can’t climb out if the water isn’t high enough for them to reach the top of the bucket. It works!

    1. Mr. Hamm, How much water? I have a Lowe’s bucket and I am curious about the water level to drown them and keep them from swimming and climbing out.

      I have some guests in my attic and they seem to be trap shy after snap traps took 3 and the electronic Victor scored 2. Camera has not picked up a thing and their traffic has shifted out of sight.

      I intend to attempt a rebait with starburst – 2nd recent recommendation for them. Peanuts and high sugar PB (Walmart Honey Roasted) is in a dry spell. Heard nutella is great (20+grams of sugar) but not sure it’s durability in a hot attic.

      Anyone try a coffee can, punctured lid with ammonia as a deterrent?

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