Bat Poison is Ineffective

ALERT: Many state wildlife agencies are now mandating the senseless killing of bats in homes and attics due to fears over COVID-19.

Many people do not want bats in their homes and buildings for legitimate reasons.  Bat guano smells terrible, and bats can sometimes make noise.  However, regardless of what kind of bat it is, it poses no risk if no one attempts to handle it.  A fear of bats and diseases caused by bats has been wrongly exaggerated in our culture, although it should be noted that bats can contract rabies (like any other animal can).  In reality, only 1/2 of 1% of bats actually carry the disease, but humans must still be extremely careful when handling them.  

There are many methods that claim to work well for removing bats from your property, but poison is never the way to go. 

It is not hard to find recommendations of using bat poison online, despite the fact that you will not easily spot a poison that is designed to kill bats.  Using bat poison is inhumane, as well as ineffective, and there are much better alternatives available. 

Reasons Against the Use of Bat Poison

There is No Registered Bat Poison

To show just how ineffective bat poison is, consider the fact that there is no poison registered as being able to kill bats.  You can find poisons marketed for killing insects and rodents, but you will not find one that is specifically designed for killing bats. 

The most common poison pest control companies use to kill bats is Sulfuryl Fluoride gas, which is a central nervous system depressant that is extremely toxic to all life forms and kills bats.  Large pest control companies including Terminix, Orkin, and several others have been shown to use this gas to eradicate bats, sometimes accidentally, sometimes intentionally, often by a service tech who wants to make a sale and who doesn’t necessarily adhere to the company’s policies.  Terminix and Orkin and other companies have denied the use of this poison when I confronted them, but in talking to dozens of wildlife control and bat removal specialists, along with pest control technicians, it is clear that these poisons have been used many times, under the radar, to eradicate bat colonies.

Other poisons used to kill bats are contact spray poisons often used to kill insects.  Examples include poisons from the Pyrethroid group, which includes compounds such as Allethrin, Bifenthrin, or Cyhalothrin, from the Organophosphate group such as Acephate or Diazinon, and the Carbamate group, such as Dioxacarb or Methomyl.

Other pest control companies use those total release foggers or “bug bombs” which use pyrethroid, pyrethrin, or both as the active ingredients. 

Some people wonder if there is a poison bats will eat, similar to rat poisons.  This creates an obvious problem, as bats would need to consume the poison to experience its effects.  The colonizing bat species in the USA only eat live insects caught on the wing, and won’t eat anything similar to a consumable rodenticide, like a rat or mouse would.

The Bats Will Not All Die

Because you cannot use a bat-specific poison, as none exists, it should not be too surprising that using a poison will not kill all of the bats on your property. You may manage to kill a few of them with an insect spray poison or even more than that, but poison is unlikely to kill all of the bats.  This holds true even if you decide to tent your house, completely covering it in insecticide for a period of time.

If you want to remove an entire colony of bats from a house or any other building, poison will not work.  Luckily, you can remove 100% of the bats, fairly easily, and completely legally and ethically, by doing a live exclusion.  This is a method that allows all of the bats to fly out of the house through what are essentially one-way doors that they cannot use to re-enter the building.  More on that process below, in the EXCLUSION section. 

bat roost

The Doses Required to Kill Bats are Dangerously High

Although there are no official poisons to kill bats, some of the poisons designed to kill other animals could produce results.  However, you would need to use extremely high quantities for that to take place.  Using high quantities would lead to other problems, especially to your health and that of your family.  Any fumigant powerful enough to kill bats would easily be enough to send you to the hospital, or cause long-term or future health problems.

Killing Bats is ILLEGAL

You also need to consider the fact that it is illegal to kill bats. This is part of the reason that there are no registered bat poisons. After all, it would be fairly challenging for a company to hide the fact that it produces and sells a product that results in illegal actions. 

If you kill bats with poison, or in any other way, and are discovered, then you will at least face large fines. That is the best-case scenario. There may also be jail time involved, depending on where you live and your situation. 

Several species of bats are protected by federal law, and most states also have laws protecting bats, or against the wanton destruction of wildlife in general.

Poisoned Bats Suffer

stuck bat

As with any other animal that is poisoned, a poisoned bat will not die instantly. Instead, it will suffer as it dies a painful death. This is inhumane.  Bats do not deserve it.

You Would Have to Deal With Dead Bats

Assume for a minute that killing bats was not illegal.  What would happen if you used bat poison and successfully killed bats with it? 

You would end up with an entirely different problem. Now, you would have to figure out where the dead bats are and get them out of your house quickly. Dead bats will rot and lead to a very bad smell, along with being a biohazard. 

Finding a dead bat is not an easy task. You cannot follow sounds like you would if the critter was alive. This is further complicated by the fact that bats may crawl into walls or other tight areas thanks to their very small bodies. You will likely need to make guesses and cut holes in walls to find the bat. 

Hiring Someone to Remove Them is Tricky Because of The Lawbat on ground

In most cases, if a wild animal dies in your home and you cannot find it, you would turn to experts and hire a professional to find and remove the critter. Of course, taking that course of action assumes that killing the animal in question is legal. 

It is believable that a single bat may have died in your home by accident, but wildlife removal experts will recognize the signs of a poisoned bat and know that you used poison. Additionally, the number of dead bats present will be a giveaway that something is not right. 

Given that killing bats is illegal, you would not want anyone to know that you have used poison to kill the mammals. 

Disposing of Them is Also Challenging

Since it is illegal to kill bats, it is also impossible to just throw them out with your garbage. Yes, you could theoretically double or triple bag them and try to hide the dead bats among your other garbage. It may work, but if someone notices that you threw out dead bats, there will be questions and you will likely be caught and have to pay fines. 

Handling Dead Bats is Dangerous

Do not forget that even the act of handling the dead bats, whether to dispose of them or find them, is dangerous due to the risk of disease. You would need extensive protective gear, including a breathing mask. 

Poison Will NOT Solve the Problem

The bottom line is that if you use bat poison to kill bats, it will be highly ineffective, as well as illegal and inhumane. As mentioned, bat poison will not kill all of the bats in the colony, especially given that no poison is designed specifically to kill these animals. 

Additionally, other bats will just come and take the place of the ones you kill, if you do successfully kill any. To prevent bats and remove them once and for all, you need to actually take care of the root of the problem, which is how they are getting into your house.

bat in grass

Benefits of Bats

Even if it were legal to kill bats (it is not), it would not be a wise course of action due to their importance to our ecosystem. Bats are a beneficial species, so reducing their numbers is harmful for people and the planet. Instead of looking for ways to kill bats, you should be in search of a method to get them off your property without harming them. 

They Control Insects

One of the best benefits of bats is their ability to help control insect populations. The FDA estimates that each year, bats take care of about $3.5 billion of pest control from eating insects. The more insects that bats eat by your house, the fewer remain to bite you, spread diseases, or hurt crops, and the fewer the pesticides being used.

They Support Cave Communities

Although bats frequently invade human dwellings, they also support the complex ecosystems found in caves. Bats are responsible for bringing nutrients into these cave communities via their guano, supporting other organisms that grow in the ecosystem. 

They Encourage Plant Growth

Bats are also known for helping with pollination and spreading seeds. The pollination benefits of bats are more specific to certain regions of the world where the bats eat nectar. Their usefulness in terms of spreading seeds comes from the bats that eat fruit. 

They Are Part of the Ecosystem, Including Prey

Additionally, bats play the role of prey in the ecosystem. Owls, falcons, and hawks all eat bats. It is also somewhat common for ringtail cats, raccoons, and weasels to attack bats.

They Help Make Alcohol

Bats are pollinators of the agave plant, which is used to make tequila.

What NOT to Do When Trying to Solve a Bat Problem

Some people may think that if bat poison is ineffective and inhumane, maybe they should try a different method of killing bats. But even if you think the law does not apply to you, there is no effective and humane way to kill bats. 

Stay Away From Glue Boards

Glue boards are a particularly problematic method of killing bats – or any other animal for that matter, such as rats, mice, and snakes. Glue boards never kill animals instantly.  Instead, they leave them out to die slowly stressed, hungry, and thirsty. Glue boards are also painful, especially when animals like bats try to twist out and escape. 

To make glue boards an even worse option for bats, it is unlikely that bats will ever land on them, so they will probably not be effective. 

Don’t Try to Kill Them

Some people may feel tempted to try to kill bats using a garden tool or a heavy object, but this is inhumane. In addition, you simply will not be successful unless you both have good aim and are very lucky. There is also a good chance that you will just anger the bat in question, leading to scratches or bites. 

Do Not Try Trapping and Relocating Bats

When it comes to non-lethal bat control methods, it may be tempting to try trapping and relocating bats. This can work temporarily, but it will never be a long-term solution.

  • First of all, this is incredibly labor-intensive.  You would need to trap and move every single bat.  Given the potential size of a bat colony, this can be impossible.  
  • There is also the fact that bats have strong homing instincts, so they will likely just go right back to your house. In other words, your efforts to trap them and release them in a new location will be for nothing. 
  • Finally, trapping and relocating bats does not get to the root of the problem. To get rid of bats permanently, you need to make sure they cannot get inside your house. 

Other Methods to Avoid

In addition to the previously mentioned lethal methods of controlling bats, there are some non-lethal methods you should avoid. Unfortunately, less reputable sites may suggest these methods, so you should be aware of them and the fact that they are harmful, ineffective, or dangerous, either to the bats or to humans. 

Anything that Blocks Ventilation

You should never use any method that will block the natural ventilation of your home, either as a whole or the specific area that the bats are in. For example, do not place plastic sheeting over the entrance.  This will change the microclimate of the roost and make it unsafe. 

Caulks to Avoid

When you use caulk as part of your exclusion method, avoid non-water-based products, including those made from polyurethane or silicone. 

Avoid Duct Tape

You also never want to use duct tape as part of your exclusion device or to attach it. This tape is very likely to do poorly in the environmental conditions of the area, thanks to mold, dust, rough surfaces, humidity, and/or rain. If the duct tape fails to properly attach or create your exclusion device, it will be worse than not working. Sometimes, the bats may end up stuck in the device or inside the space. 

Avoid Expandable Foam

You should also avoid the use of expandable foam as part of your exclusion or home repairs. The foam may block ventilation, which is already something to avoid. Additionally, the foam might break down when it gets warm, which would give bats a space to get back inside. Additionally, before it dries, the foam can kill bats. It is not uncommon to find bats entombed in this type of foam. 

Netting for Exclusion – Unless You Are a Professional

The average person should also avoid using netting as an exclusion device. This method does work, but you have to set the netting up carefully to ensure that it works and to minimize the risk that bats will get tangled. This method is best left to professionals who have experience using it, and even then, many prefer other exclusion methods.

Exclusion:  The Best Solution

If you are dealing with unwanted bats on your property or inside your home, then the absolute best method to remove them in a humane and legal manner is to use exclusion.  

With exclusion, you essentially seal up nearly every single entry point that bats can use to get into your home. In most cases, this means focusing on the attic or chimney, as that is where the bat colony is most likely to be. You leave one entry point open and cover it with an exclusion device, also known as a one-way door. This device will let bats out, but prevent them from getting back inside. Once you are sure that all of the bats are gone, you can remove the exclusion device and seal up the final hole. 

Do NOT Exclude During Maternity Season

Before you start excluding bats from your attic, chimney, or another area, make sure that it is not the maternity season. This is when bats give birth and mothers still care for the young. It is frequently illegal to exclude bats during this time. Even if it is not illegal, it is highly immoral. 

Keep in mind that if you were to use exclusion during this time, the young bats would not yet be able to leave, but the mothers would. This would result in you excluding the mother bat from her young with no way to reach them. Not only will this cause the mother unnecessary stress (and causing her to scratch frantically against your house, possibly damaging it), but you will also be sentencing the young bats to certain death as they will have no food. 

To avoid maternity season, avoid exclusions from April to late August. The season tends to start in mid-April in southern portions of the United States.  In the northern states and Canada, the season begins in mid-June. Expect the young bats to be ready to fly by the time August comes to a close.  

Do NOT Exclude Hibernating Bats

Although you may not realize it, not all bats that take up residence in houses will spend the late fall and winter somewhere else. Some may choose to hibernate in your attic as their safest option for a warm, dry spot. There are just several species that may hibernate in buildings, but they exist and should be considered.  

If you have hibernating bats and it is winter, then wait for a few months before excluding the bats. The weather is too cold for them to survive, and you will not be successful at excluding them while they are hibernating, anyway. Instead, wait until spring.  Once you see the bats have started coming out to feed, you can go ahead with the exclusion. 

Do NOT Exclude During Bad Weather

Even if you live in an area where bats do not hibernate indoors, avoid excluding them in poor weather conditions. In cooler weather, for example, there may not be flying insects around. As this is their food source, the bats would have nothing to eat if you exclude them. 

Additionally, you should not exclude the bats during any severe weather, including heavy wind or rain, or if severe weather is expected. This would dramatically reduce the bats’ chances of survival. 

Making an Exclusion Device With Tubes

If you choose to make an exclusion device instead of buying one, the easiest way to do so would be by using a tube. Tubes do particularly well for openings on buildings that feature rougher exterior walls, like a stone or brick house or a log cabin. Additionally, tubes do well in areas like corners, on soffits, or on other horizontal surfaces. 

You want to choose a tube that is about two inches in diameter and around ten inches long. Use flexible plastic tubing or PVC pipe. You could also take an empty caulking tube and cut off the ends, but make sure the tube is well-cleaned. The tubes will work well because bats cannot cling onto them, thanks to their smooth surface. The benefit of using a flexible tube of some sort is that you can squeeze the end, allowing it to fit into a tighter space. Alternatively, you could cut an end to create a flap that will fit over the opening.  Attach it with screws, staples, nails, or caulk. 

Place your chosen tube securely over the entrypoint.  Use clear, lightweight plastic to supplement it. This is not necessary, but when applied properly, it can ensure that the bats will be even less likely to reenter. You would tape this plastic around the outside end of the tube. 

How Long to Keep an Exclusion Device in Place

Any time you are dealing with bats, you need to make sure that you do not trap them inside your home or attic. As such, you want to ensure that you leave the exclusion device in place for long enough. Ideally, you will want to wait at least a week. If you only had a few bats, you may not have to wait this long. Regardless of how long you wait, you must always check that no bats are still inside before sealing up the final hole.

The Bottom Line

Bats are an important part of the ecosystem and a protected species in many areas.  There is no registered bat poison, and using any product to try to poison bats will be inhumane, ineffective, and illegal.  Instead, turn to exclusion as a method to get bats out of your property.  You can try exclusion yourself, but you will get the best results if you hire a professional, as they are experienced in this manner and know how to find the various bat entry points.