Bat Extermination

How to exterminate bats with fumigants, and pesticides - People try many different methods for exterminating bats in buildings, including the use of fumigants. Since there are no poisons or fumigants that are made specifically for bats, some people will try things like spray fumigants meant for insects. A common method of treating for insects includes "tenting" the whole house, then using a fogging poison such as phosphine, 1,3-dichloropropene, chloropicrin, methyl isocyanate, hydrogen cyanide, sulfuryl fluoride, formaldehyde, or Iodoform. Some companies use poison agents such as DDT or RoZol, which are not legal for use in the U.S., and are just as harmful to humans as they are to bats. I've heard of a couple of cases in which people have tented their house with Vikane Gas.

It is very important that you know that these insect poisons are not meant for, and will not work properly, on bats. Bats are not bugs! Luckily it's rare that a person uses poison, but each of the cases I've heard about in attempting to gas bats to exterminate them has resulted in disaster, as distressed bats made their way into the living quarters, some bats died, some not, some bit the inhabitants afterward (necessitating rabies shots), and in one case, a $30,000 fine was issued by the state wildlife commission for and wanton destruction of wild resources.

Use of bat pesticides (well, there are none, legally and technically) or poisons is immoral, but most of all, flat-out ineffective! You wind up with worse problems than you had before you started! NEVER hire a bat extermination company that uses poisons or pesticides for bat control. That would be grossly ignorant. In fact, if you hear of such a company, email me or report that company to your state's wildlife commission or the Environmental Protection Agency. Seriously!



What is the cost to exterminate bats? Well, if you follow the below instructions, it's free, and better yet, you won't kill a single bat! If you do need to hire a professional, the cost can vary a great deal, depending on the size of the bat colony and the amount of sealing needed for your house. The price could be as cheap as $300, or as much as $1000 or more.

Here are instructions for how to remove bats without exterminating them:

STEP 1 - Inspection: You have to find out how the bats are getting in and out of the building, where they are living, what species they are, and what damage they have caused. They fly out at dusk, and fly back at dawn. Not all at once, and they make several trips in and out per night. They usually roost in tight, hot areas in the structure. They usually crawl down walls and wedge into gaps behind wood beams, fascia boards, etc. They can leave millions of droppings (guano) all over your attic. First you need to watch the house at dusk to see the bats flying out, then you need to inspect the house, on a ladder, to find all the entry holes.
STEP 2 - Pre-Sealing: The bats usually have several entry holes and gaps leading into the house. The key to a proper bat removal project is to find all of these areas. The holes and gaps are usually tiny, about a half-inch (yes, a half-inch), and very easy to miss. In order to remove the bats, you have to funnel them out. But if they can enter via dozens of spots, you want to seal off potential entry holes beforehand. Never seal a primary entry/exit spot before an exclusion. An expert can easily tell the difference. Read more about how to seal your house against bats here.
STEP 3 - Exclusion: Install one-way exclusion devices on the primary entry/exit areas. Depending on the architecture, this may be exclusion netting, screening, funnels, or cones. Every building is different, and the bats relate to the architecture in very specific ways that require selecting the proper device(s). The exclusion netting or funnels must be set perfectly to allow bats to fly out naturally at night, but then not be able to fly back in. That is the main principle. Simple in concept, but very hard to get right! And it is crucial that it is done perfectly, or you'll have a big problem on your hands. Read about the bat exclusion process.
STEP 4 - Seal-Up: After you are 100% certain that all the bats are out, remove the exclusion devices and seal the entry holes shut. Bats live a long time and remember for a long time, and will attempt to re-enter the building for a long time. Perhaps for the next few seasons. But they are fragile animals, and they can't claw or chew their way back in, so if you do your job right, you'll never have bats inside again. A variety of materials work well, from plastic or metal screening, to caulk, to high density polyurethane, depending on the situation.


HELP: If you need professional help in solving your bat problem, please click on my Hiring Advice and 2017 Directory of Bat Removal Professionals serving every city in the USA.

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Wildlife Education - Information and Advice for the Safe Removal of Bats from Attics