Everything You Need to Know About Mosquito Dunks and Bits

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Mosquito dunks are an effective, natural and non-toxic way to get rid of all your mosquito problems. But when you read about them in the internet, you sometimes get a bombardment of words – words you might not even need.

So here, we’ve gathered only the most important things that you should know about this easy pest treatment.

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Mosquito dunks are a popular option for homeowners with water features in their yards. CC Image courtesy of Mike Mozart on Flickr

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What are mosquito dunks?

You can compare mosquito dunks to Insect Growth Regulators for fleas. This pest control product only kills the mosquito’s developing population. Specifically, it targets the mosquito larvae that live in stagnant water.

Mosquito dunks are tiny donut-shaped pellets that are considered as a biological pesticide. It’s not as poisonous as chemical treatments, but it’s not less effective either. That’s because dunks are made out of a naturally occurring soil bacterium called Bacillus thuringiensis (Bti), an active microorganism that produces toxins that can kill mosquitoes, fungus gnats and black flies in just a short amount of time.

What are mosquito bits?

Mosquito bits are roughly the same as dunks. They’re made from the same microorganism, and they work in the same way. However, they do differ in size and the time it takes for them to show results.

Mosquito dunks work slowly, taking a few hours to release its Bti. But its effect on stagnant water does last for at least 30 days. That means it takes that amount of days before that specific body of water will potentially be infested with larvae again.

In contrast, bits are formulated to remove mosquito larvae quickly, just within a couple of minutes. However, its quick-release formulation comes with a price because unlike dunks, bits only take 7 to 14 days before its effects wear off.

How do they work?

Using this product is simple. It only takes a few steps. Here’s a quick guide on how you should do it.

  • ​Place the mosquito dunks or bits on any stagnant water.
  • The dunks have “donut holes” in them so you can attach to something.
  • Bits can just be scattered over the water.
  • After a few minutes, they will gradually sink down, slowly releasing the Bti. This will also be the time that the larvae will start consuming the bacteria.
  • Finally, leave the products to completely dissolve in the water. The larvae will have started dying by then.

The treatment is that easy. And you can use it in any kind of still water, just as long as it’s not chlorinated. Old pools, barrels, gutters, ponds, and outdoor baths are only some of the places that you can use these products on.

Just remember the correct proportions. Here’s a short list from Insect Cop that details how much dunk you can use in one setting:

  • ​1/4 mosquito dunk for 1 to 5 square feet of large water areas (0.1-0.5 square meters)
  • 1/2 mosquito dunk for 5 to 25 square feet of large water areas (0.5-2.3 square meters)
  • 1 mosquito dunk for 25 to 100 square feet of large water areas (2.3-9.2 square meters)
  • More than 1 mosquito dunk in areas bigger than 100 square feet (9.2 square meters)

Are mosquito dunks and bits safe?

Generally, bits and dunks are safe when they’ve already been dissolved, so they’re not known to hurt humans and animals. However, their solid forms tell another story.

If these products have not been melted down, they can be dangerous when consumed by pets. The Bti can cause cats and dogs sever stomachaches and nausea. So if it’s been eaten, you should go to a vet right away.

Also, many experts still warn users to not use this product in drinking water. You shouldn’t get treated water near your eyes and open wounds either. Even if it hasn’t been thoroughly researched on, the Bti might wreak havoc on your body.

Mosquito dunks and bits may be useful when you’re trying to get rid of your home’s mosquito problems, but it should never be taken lightly.