Wildlife Control Methods

January 16, 2021 by Stephen M. Vantassel

Carbon Monoxide for Rodent Control

The combination carbon monoxide for rodent control may seem a bit forced, but the use of carbon monoxide devices for rodent control is growing throughout the country. There are several reasons for the growth in the use of carbon monoxide for control of rodents. Let me list a few.

Carbon monoxide devices are not regulated by the EPA. The EPA (Environmental Protection Agency) regulates the use pesticides in the United States. But the EPA does not regulate devices. Therefore, pest control operators (PCOs) and wildlife control operators (WCOs) do not need to obtain licenses to use carbon monoxide machines to control rodents. Now states can regulate devices but to my knowledge, none have done so as of January 2021. Colorado regulates how close these devices can be used to occupied structures but does not require a license to use the devices.
Carbon monoxide for rodent control is produced by this device called Burrow Rx
Carbon monoxide doesn’t cause secondary poisoning. More and more customers are concerned about the secondary poisoning risks of traditional anticoagulant rodenticides. They are worried (often with a concern greater than the evidence permits) that their free-range cat or dog or that of the neighbors will eat poisoned rodents and get sick or possibly die. Carbon monoxide leaves no residual in the animals it kills. So if a dog or cat eats a rodent killed by carbon monoxide it will not be harmed by the carbon monoxide. Now the dog or cat may get sick from something else (wildlife carry various diseases that may affect your pet) but it won’t be from the carbon monoxide treatment.
There are various devices available. Make no mistake, the easier you make it to do something the more likely that something will be done. Same is true for carbon monoxide devices. Manufacturers have created carbon monoxide devices with different features and price points. Products include, Pressurized Exhaust Rodent Control, Burrow Rx, Rascal Eliminator, and The Cheetah. There could be others.

Carbon monoxide for rodent control is here to stay as long as regulators don’t regulate the convenience out of the technique. While carbon monoxide for rodent control has many benefits, there are several disadvantages. But that is a story for a future blog.

Stephen M. Vantassel, CWCP, ACE, is the owner of Wildlife Control Consultant, LLC. He helps people restore their balance with nature through publishing, training, consulting, and the internet. He has published numerous articles in trade and academic publications available at {Stephen’s Academia.edu Page} along with several books {WCC Store}). Listen to his podcast “Living the Wild Life” at {Pest Geek Podcast}. Please subscribe to {Stephen’s YouTube Channel} He is a sought after speaker and trainer. If you would like to have Stephen speak at your event or use his consultation services, send an e-mail to [email protected] Copyright All postings are the property of Stephen M. Vantassel and Wildlife Control Consultant, LLC. Text (not images) may be reprinted in non-profit publications provided that the author and website URL is included. If images wish to be used, explicit and written permission must be obtained from Wildlife Control Consultant, LLC.

October 17, 2020 by Stephen M. Vantassel

Deer Repellents

With the end of the growing season, homeowners should be thinking about protecting their plants from hungry white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus). While population reduction (i.e. hunting) is an excellent way to reduce browse damage, many communities prohibit hunting. Thus the only options left are deer repellents or fencing. Homeowners choose deer repellents because of trust in chemicals and a desire to avoid unsightly fences and barriers.

Bottle of Plantskydd Deer Repellent — Plantskydd is a fear-based deer repellent.

Categorizing Deer Repellents

Deer repellents are categorized in two different ways: mode of action and application method. Mode of action refers to how the product deters animals. Deer repellents work in one of four different ways, pain, taste, fear, and aversive conditioning.

Pain-based repellents elicit some irritation in the deer when the deer bites the plant. Chemicals used to elicit pain include, capsaicin, ammonia, and peppermint.
Taste-based repellents try to make the plants taste bitter or unpalatable to the deer. Taste repellents are often combined with one of the other repellent types by manufacturers hoping to increase the product’s efficacy. Lots of chemicals used to achieve this end.
Fear repellents utilize predator-like odors to make the deer think that carnivore (meat-eating animal) is nearby. Chemicals in this category include, putrid egg solids and predator urines.
Lastly, aversive conditioning is a repellent that causes an illness in the deer following eating the treated plant. The deer remembers where it ate and how it felt and then continues to avoid the location. Chemicals in this category include, ammonium soaps of fatty acids and thiram.

Why Understanding Mode of Action Matters

Understanding deer repellent mode of action is important because many repellents with different names and brands are alike. Only by reading the label and understanding what the active ingredient is can you properly distinguish a product that didn’t work for you from another. Failure to read the small print may result in your purchasing the same mode of action under a different name.

Stay tuned for more information on deer repellents in an upcoming blog.

July 11, 2020 by Stephen M. Vantassel

Possible Snake Repellents

Did I just write the heading, possible snake repellents? Doesn’t that statement conflict with an earlier blog post about the relative inadequacy of mothball-based snake repellents, see Snake Repellents? Well the short answer to all that is, “Yes, but with a caveat.” An interesting article by Larry Clark and John Shivik, entitled, Aerosolized essential oils and individual natural product

white garter snake photo — White garter snake may cause some people to be frightened enough that they would buy a snake repellent.

compounds as brown treesnake repellents, published in 2002, in the Pest Management Science journal (58:775-783, DOI: 10:1002/ps525) shed some interesting light on several possible snake repellents.

Clark and Shivik’s Article in Brief

Brown tree snakes (Boiga irregularis) are an invasive (and dangerous) species that since their introduction to the island of Guam have been responsible for significant declines in the island’s native bird species. Since officials want to avoid transporting these snakes to other islands, finding an effective repellent would be an important tool in the tool box for managing this dangerous species. Since the cost of registering a non-food based repellent with the EPA is enormous, these scholars sought to evaluate essential oils. Essential oils, many of which are already used in food or air fresheners would require a lower barrier to EPA registration.

Clark and Shivik investigated the effect of 14 essential oils not counting water on snakes followed by an analysis of 20 specific chemicals which were key components of those essential oils. Essentially the test was as follows. First snakes were tested to see if they reacted to a squirt of water. If they didn’t react they were used in the study. Reactions were evaluated as either vigorous motion, slow motion or no motion. Vigorous motion was when the snake reacted violently to the sprayed oil or chemical. Slow motion was the snake’s reaction was more investigative as if it was trying to look around. No motion should be self explanatory.

Results of the Snake Repellent Study

The authors found that snakes reacted significantly to cedarwood, cinnamon, sage, juniper berry lavender and rosemary oils. As for individual chemicals, snakes reacted vigorously to aerosols of m-anisaldehyde, trans-anethole, cineole, cinnamaldehdyde, citral, ethyl phenylacetate, eugenol, geranylacetate or methyl salicylate.

Bottomline

Before you go out and buy some essentials and start offering snake repellent services, you need to keep a few things in mind.

These products were tested on brown tree snakes. Not garter snakes, etc. Does that matter? It might.
None of these products/chemicals have been registered by the EPA for use as snake repellents. Don’t break the law!!!
None of these products were tested as barrier repellents. Meaning, they weren’t tested to see if a snake would avoid an area with these chemicals. The authors noted that these chemicals may be better characterized as flushing agents. In other words, these products may find a use as a way of seeing if a snake is present in a shipping container or crawl space. Fog the space and see if the snake emerges or shows himself. While developing flushing agents can be important for WCOs or PCOs, they are unlikely to do much for the bottom line even if the EPA did register them. So patience folks. As of this blog, there are no known barrier chemical repellents yet, at least for American snakes, that I know of. The search and the wait continues.

June 20, 2020 by Stephen M. Vantassel

Y Stick

The Y Stick

I had been fairly happy with using “y” sticks as holders for bait in my cage traps. They were cheap (free) and worked really well. But my honey moon was soon over when I started having some problems. Some times I would have to spend too much time searching for bait sticks. It seemed that some residents kept their property cleared of broken branches and trimmed their trees. It just didn’t look good raiding some bush for a usable “y” branch. Sure I would stock up on them when I had the chance but they would sometimes break as from the jostling they got in the back of my truck. Traps moving in and out, bait containers being tossed inside would be too much for the dry sticks to handle. I needed another option.

PVC bait stick and y stick — PVC bait stick (left) and the Y bait stick (right)

The other problem with the “y” stick was that the two ends protruded above the cage. You might not consider that a big problem. It isn’t when the weather is warm and dry. But I live in New England. I often want to protect my bait and trigger area from snow and rain. The “y’ stick prevented me from laying stones or boards above this area. Doing so would only break the sticks or roll the angle of the stick into a bad angle making it too easy for an animal to misfire it. I needed another option.

In comes the PVC bait stick. I think I learned this from Rob Erickson but my memory could be wrong as there was another gentlemen in the Massachusetts and Connecticut area that also mentioned it. Anyway, the principle of the PVC bait stick is the same as the Y stick but with additional benefits. First, it is durable. Second, it disperses odor from the paste bait better. Finally, being white, it shows up better in low light conditions, which I think enhances the enticement for animals.

If you would like to create your own PVC bait stick, just watch the video below.

Want to learn more about baiting cage and box traps, take our 1 hour training course.

May 30, 2020 by Stephen M. Vantassel

Mothballs as Repellents

How many times have you heard of people using mothballs to repel wildlife? I wish I got a dollar for every time I heard someone tell me that mothballs helped him/her or their neighbor resolve a wildlife complaint. Why do so many people think that these round white balls actually work?

Image of the cake version of mothballs — Mothballs are made from paradichlorobenzene or naphthalene. Photo: FarmerCarlos/Wikimedia 2009.

Do Mothballs Repel Wildlife?

Well, people think mothballs work to repel wildlife for a few reasons. First, sometimes they actually do work. Yes, you heard it from me. The fact is mothballs do, in certain situations repel wildlife. Mothballs, whether they are made from naphthalene or paradichlorobenzene, give off an odor that is noxious to animals. But they only repel animals if the gas concentration is high enough. Typically, gas concentrations can only get high when used in amazing quantities and within a closed space. That’s the rub. Tossing a handful of mothballs into the attic will not drive your squirrels out. If you pile mothballs every few feet in the attic, then you will likely drive the squirrels out. But in doing that, you will have not only violated the law (i.e. mothballs are pesticides and using them in a manner that goes beyond the label instructions violates EPA regulations) but you will likely be creating conditions that drive you and your loved ones out of the house to get away from the noxious fumes.

Why You Shouldn’t Use Mothballs

You shouldn’t use mothballs to repel wildlife because not only is it illegal to use pesticides in a manner that violates the label (mentioned above), but mothballs can harm your health and those you love. If your exposure to mothballs (naphthalene version) is high enough, such as through inhalation or ingestion, you can suffer from acute intravascular haemolysis. Acute intravascular haemolysis is a fancy term for, your red blood cells break down. If your exposure to mothballs (paradichlorobenzene version) is high enough you can suffer from anemia.

What about the effects of long-term exposure? This is a difficult question to answer but researchers believe that long-term exposure to mothballs (regardless of version) could cause cancer. Nevertheless, you never want to be in a situation where you are exposing yourself to a chemical unnecessarily. And to be blunt, you should never need to be using mothballs to manage wildlife.

There are plenty of effective alternatives available as contained in my book, The Wildlife Removal Handbook, 3rd ed. or through consultation.

Carbon Monoxide for Rodent Control

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