Tag Archives: sugar

Yeast-and-sugar mosquito control devices

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In the United States, nine companies are selling containers filled with water, sugar, and yeast for mosquito control. The marketing pitch is that mosquitoes are attracted by carbon dioxide (produced by yeast consuming the sugar), enter the device through holes, crawl inside, ingest some of the fluid, crawl back up to the holes, exit the container, and then die (e.g., by exploding) due to the effects of a chemical (table salt, boric acid, garlic oil, etc.) dissolved in the fluid. Some of the companies claim their tubes will rid a yard of mosquitoes for three months. I summarize the devices below. You can skip to the end if you just want to know whether they work.

1. Spartan Mosquito Eradicator

First sold in 2016 as the Spartan Mosquito Bomb, the company says these tubes will eradicate up to 95% of mosquito population for up to 90 days. Ingredients are sugar, yeast, and salt (purchaser adds water). I reviewed it in 2019. Below is an infomercial featuring Spartan Mosquito’s Chief Chemist, Chris Bonner:

2. Sock-It Skeeter

It’s identical to the Spartan Mosquito Eradicator except it’s a bag instead of a tube. Contains sugar, yeast, and table salt. Made by Spartan Mosquito but listed under a shell company in Florida (details). Here’s one of the commercials:

3. Donaldson Farms Mosquito Eliminator

Like the Eradicator, the Eliminator is marketed to rid yard of mosquitoes for 90 days. Contains sugar, yeast, citric acid, calcium carbonate, salt, and sodium lauryl sulfate. This device doesn’t appear to registered in any of the states that require registration. Based in Chattanooga, TN.

Donaldson Farms Mosquito Eliminator

4. Mosquito XT

The Mosquito XT contains sugar, yeast, baking soda, and salt. This device doesn’t appear to registered in any of the states that require registration. Based in Paragould, AR (details), the owners run an insurance agency. Here’s a pic from the website:

Mosquito XT

5. Spartan Mosquito Pro Tech

This device is uses boric acid instead of salt as active ingredient, but still contains sugar and yeast (both as unlisted, inactive ingredients). Company says tubes kill mosquitoes for up to 30 days. California banned it after reviewing efficacy data. I reviewed it in 2020. Here’s the inventor, Jeremy Hirsch, on a 25-min Q&A with one of the retailers (note that video glitches out several times):

6. Aion Mosquito Barrier

Company says the tubes “kill and repel” mosquitoes for 90 days. Contains sugar, yeast, and table salt. It was first marketed as The Mosquito Eradicator (picture below). Based in Memphis, TN. Website. Here’s an ad:

7. Skeeter Hawk Backyard Bait Station

Contains sugar, yeast, citric acid, calcium carbonate, and garlic oil. Based in Grand Prairie, TX (details). Below is an ad:

8. Grandpa Gus’s Mosquito Dynamiter

Company claims the device will eradicate up to 95% of mosquitoes for up to 90 days and asserts that mosquitoes “literally explode”. Contains sugar, yeast, and table salt. Made by Vic West Imports of Austin, TX. Here’s an ad that I found on Facebook:

https://twitter.com/colinpurrington/status/1301506601644421120?s=20

9. Tougher Than Tom’s Mosquito TNT

Company claims that mosquitoes explode after drinking the fluid (sugar, yeast, salt). Owned by Simply Strive (Zachary Collins) of Austin, Texas. This device doesn’t appear to be registered in any of the states that require registration of minimum-risk pesticides. Below is an ad followed by a review.

10. Solution X

Per the box, “clears away 95% of mosquitoes.” Based in Memphis, TN (details). Parent company is EnviroChem, a distributor of cleaning compounds. I couldn’t find a commercial or a website but here’s the box layout that they send to state pesticide regulators:

11. Greenerways Mosquito-Bite FreeZone

Claims to lure mosquitoes and then jam their receptors, creating a mosquito-free area with 100-foot radius for seven days. Lists soybean oil as the active ingredient, but also has sucrose, yeast, and essential oils. Available on Amazon and many other online retailers. Greenerways LLC is based in Yardley, PA. Here’s a video ad (screenshot below).

Do they work?

To my knowledge, there’s no evidence that any of the above devices kill or repel mosquitoes when they are deployed outside. There’s evidence they don’t work, though. For example, scientists in Florida tested the Spartan Mosquito Eradicator and concluded it wasn’t effective. And scientists have also established that salt water doesn’t kill mosquitoes, so all the devices that list sodium chloride as the active ingredient (most of them) are not going to work at all. Finally, in my testing of the Spartan Mosquito Pro Tech, mosquitoes are not even attracted to the containers, which, if generalizable to the other products, makes it unlikely these products would do anything even if they had an active ingredient (like boric acid) that is lethal mosquitoes.

Here are photographs showing what is inside a Spartan Mosquito Eradicator (left) and a Spartan Pro Tech (right) after several weeks. Plenty of picture-wing flies, fruit flies, ants, and molds. But no mosquitoes. I’ve never even seen a mosquito come near these tubes.

Dead flies inside a Spartan Mosquito Eradicator
Fungal growth, dead flies, and dead ants inside a Spartan Mosquito Pro Tech

If you’d like to see the full array of insects and spiders that these tubes killed, I’ve collected them on iNaturalist.

Why are these companies still in business if their products don’t kill mosquitoes?

I think there are four reasons.

  1. Towns, municipalities, and regional health departments often spray adulticides from trucks and airplanes, in the middle of the night, without many residents being aware. And if some of those people have yeast-and-sugar tubes hanging in their yards, they might wrongly assume the lack of mosquitoes is related. This scenario is probably common because spraying happens pretty much at the exact time of the year that homeowners place the yeast-and-sugar containers around their yards. For those curious about Mosquito Abatement Districts, this article has a nice summary. You can also ask your local government for details on whether your house is being treated.
  2. Sometimes due to sudden and extended drought conditions, mosquito populations plummet. Again, people might not appreciate that the lack of water is preventing mosquitoes from completing their life cycle and will mistakenly attribute the drop to yeast-and-sugar devices they deployed around their yards.
  3. Many of the companies encourage homeowners to hang the tubes before the start of the mosquito season. It might seem to some that the tubes are keeping the mosquitoes at bay but in reality it’s because the mosquito season hasn’t started.
  4. Finally, some homeowners spray pyrethroid-based insecticides (like those used by Mosquito Shield and the like) in addition to deploying the yeast-and-sugar contraptions. I’ve seen comments on the internet suggesting that these people believe both are necessary even though in reality the tubes are merely decorative.

Once a person becomes convinced that the tubes work, they are unlikely to abandon that belief even when presented with clear evidence to the contrary. That’s probably especially true if a person tells multiple neighbors that the devices work. I.e., a person becomes personally invested in that belief. Indeed, when the tubes fail in future summers (or during gaps in municipal spraying), true fans of these tubes go to great lengths to blame themselves. For example, they might say, “I don’t think I used the correct temperature of water”, “I may have placed them too close to my house”, or “I should have used a few more tubes.” The companies use the same lines in response to consumer complaints, never acknowledging that the failure is with the tubes themselves.

It’s also worth pointing out that the majority of people who try these tubes conclude that they are ineffective and never buy them again. They lose $50 bucks, or whatever, and chalk it up as a mistake and get on with their lives. Some might pursue a refund but I think most people are too lazy to ask. One of the companies, Spartan Mosquito, even sets its return window to expire 30 days after product is delivered, not after 30 days of use — for a product that is supposed to kill mosquitoes for 30 days, that’s a pretty clever way to make sure nobody can get their money back. I.e., if people try it for 30 days and conclude it’s a garbage product, the return window is already over. And the companies still make a profit because the core subset of true believers (several million Americans in total) will keep spending hundreds of dollars each summer on new tubes. That’s enough to make the owners of these companies millionaires, and explains why more and more people are getting into the market.

People often mention that the reviews for these types of tubes are generally high, and use that fact to argue that the products must, in fact, work. For example, the Spartan Mosquito Pro Tech has a 4/5 rating on Amazon. I’m of the opinion, however, that even completely useless products can get ratings like that. For example, OFF! citronella candles get a rating of 4.2 even when “not intended to repel mosquitoes” is prominently displayed on the packaging (that’s correct: citronella candles do not repel mosquitoes).

Please consider sharing this post on Facebook or Nextdoor so that your friends and neighbors don’t get sucked into the scam.

Indoor mosquito trap made from plastic soda bottle

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Here are instructions for building a mosquito trap using a 2-liter plastic soda bottle. All you do is add some bait (honey, fruit, juice, sugar water, or some nectar-containing flowers) and place in a dark corner of the room. It works because mosquitoes seek out sugar, which they require to fuel themselves. Once inside the bottle they can’t get out.

DIY plastic bottle mosquito trap
Printable version

The above instructions are a modification of a Taiwanese science-fair project that eventually went viral. The differences between the original instructions and mine are that (1) I don’t recommend adding dry active yeast, (2) I suggest sugar sources other than granulated sugar, and (3) I don’t wrap trap in black paper. The omission of yeast is because I don’t think the generation of carbon dioxide is necessary to attract mosquitoes to sugar. In fact, adding yeast likely reduces the attractiveness and causes the trap to fail faster.

The critical part of the original instructions is to deploy the device on the floor in a corner of a room. This is because mosquitoes love to hang out in corners — they are dark and relatively free of desiccating drafts.

Why it works

Mosquitoes are famous for sucking blood, but like many insects they spend most of their lives quietly ingesting sugar from flowers and rotting fruit. For example, here are some mosquitoes nectaring in the middle of the day:

Psorophora ferox
Aedes albopictus (Asian tiger mosquito) nectaring on swamp milkweed
Aedes albopictus

So when mosquitoes find themselves trapped inside, they will zero in on whatever you have on the countertops — fruit, puddles of syrup, cut flowers, or even a dirty sponge. I don’t have photographs of mosquitoes eating fruit inside but Justin Yoshida (Thailand) does: on jackfruit, on apple slices, and on eggplant. Mosquitoes indoors are likely not especially picky about fruit type because the option is starving to death. Mosquitoes even fall into juice containers and die, apparently, as one restaurant discovered. And here’s a mosquito eating brioche goop at my house:

Asian tiger mosquito

In case you’re skeptical that these traps can actually work, here’s a video by somebody who followed the original (science fair) directions and killed 9-10 mosquitoes in 24 hours:

Tips

  1. The original instructions suggest 50 g (~1/2 cup) sugar and 200 mL (~1 cup) water but the ratio probably doesn’t matter at all. Brown sugar is likely better than granulated (white) sugar because it has more impurities (some of which are volatile). A drop of rose water might make the sugar mixture more attractive.
  2. Make traps with different types of bait to see which ones are most attractive to the species that are local. Anopheles coluzzii, for example, seems to prefer papaya and banana juice over mango juice (Nignan et al. 2020). Other species might prefer oranges. Or, perhaps, durian.
  3. Replace your bait when it stops attracting mosquitoes. Perhaps every four days if you use fruit (Meza et al. 2020).
  4. If you use flowers, opt for ones that have nectar (if you know) and are light-colored. Or stick a small potted orchid inside the bottle — their blooms last for weeks.
  5. If you happen to have a plant with extrafloral nectaries, that’s a great bait that will likely last for a long time (when you’re on vacation, for example). Try a bunch of wild cherry leaves, for example.

Why it won’t work outside

Don’t bother using these traps outside (the recommendation of the viral versions). Mosquitoes prefer natural sources of sugar so they will likely ignore anything inside a container. The traps will also not work in rooms full of flowering plants or decomposing fruit. Similarly, if your kids spill juice and soda everywhere, the traps won’t work.

Adding toxins to the mix

If you have a house free of small kids and meddlesome pets, you can add bit of boric acid to the solution to create an attractive toxic sugar bait (ATSB) station. Then, when mosquitoes ingest the fluid they will die even if they manage to escape the trap (it can happen). In fact, once you have a toxin in the fluid you can and should just get rid of the funnel part of the trap — its presence is likely a barrier to some mosquitoes even though it’s relatively wide (~2 cm). Instead, cut a 3 cm hole in the side and keep the cap on the bottle. Note that because these devices are indoors you don’t need to worry about the boric acid (or whatever) poisoning the pollinators in your yard.

The above is nicely explained by Andy Lee Graham:

Anne Barone writes that blackberry wine pairs well with boric acid.

Note that fermentation will occur even though you haven’t added any yeast. Fungal spores are present everywhere.

Commercial, outdoor versions that contain yeast

In the United States the following “yeast and sugar” products are advertised to kill mosquitoes outside: the Spartan Mosquito Eradicator, the Spartan Mosquito Pro Tech, the Sock-It Skeeter, the Donaldson Farms Mosquito Eliminator, the Mosquito XT, the Aion Mosquito Barrier, the Skeeter Hawk Backyard Bait Station, Grandpa Gus’s Mosquito Dynamiter, Tougher Than Tom’s Mosquito TNT, and the Solution X. I’ve reviewed them all here (they don’t work).

© 2021 COLIN PURRINGTON