You have probably heard of Mosquito Dunks. But how do Mosquito Dunks work? The answer is simple—even though it involves some science. Summit Mosquito Dunks kill mosquito larvae, before the larvae can develop into adult mosquitoes.
I will explain exactly how Mosquito Dunks kill mosquito larvae in just a moment. But first it’s helpful to learn a little bit about mosquitoes.
How Do Mosquito Dunks Work: Fast Facts About Mosquitoes
It has been said that, ounce for ounce, mosquitoes are the deadliest creatures on planet Earth. An adult female mosquito weighs just 1/15,000 of an ounce (that’s about 2.0 milligrams). But despite mosquitoes’ tiny size, mosquito bites kill an estimated 1 million people worldwide each year. That’s because mosquitoes transmit some of the planet’s most deadly diseases including malaria, dengue, yellow fever, and West Nile virus.
Only female mosquitoes bite—and they bite people, animals, and birds. (Male mosquitoes feed solely on flower nectar.) When a female mosquito bites, she removes a tiny bit of blood. She needs the protein in the blood to develop eggs, which turn into the next generation of mosquitoes.
Where Do Mosquitoes Lay Their Eggs?
Female mosquitoes lay their eggs in standing water. Basically, any standing water will do. Ponds, puddles in low areas of a landscape, birdbaths, child swimming pools, an abandoned tire, or a bucket left out in the yard can all serve as mosquito breeding grounds.
Some species of mosquitoes can lay their eggs in as little as a bottlecap full of water.
A female mosquito lays her eggs in shallow, stagnant water. It can then take as little as a few days for the eggs to hatch into larvae. The larvae develop into pupae, and the pupae develop into adult mosquitoes. The entire life cycle from egg to adult takes about 8-10 days.
So, How Do Mosquito Dunks Work?
The active ingredient in Mosquito Dunks is a naturally occurring, microscopic bacterium called Bacillus thuringiensis israelensis. BTI for short. The BTI bacterium is deadly to mosquito larvae but harmless to other living things. Unlike chemical insecticides, BTI is target specific. It ONLY kills mosquito larvae.
Mosquito Dunks are made in the USA by Summit Responsible Solutions, based in Baltimore, Maryland. As Summit has been saying for many years, Mosquito Dunks kill mosquitoes before they can become flying, biting, disease-spreading adults. Basically, BTI is Mother Nature’s own mosquito control.
To kill mosquito larvae in any standing water, simply drop in a Mosquito Dunk. As the Dunk floats on the top and slowly dissolves, it releases the BTI into the water. A mosquito larva eats the BTI spores, which release toxins into the larva’s gut. This causes the larva to stop eating. It dies before becoming a pupa.
There are approximately 2,500 species of mosquitoes. The BTI in Mosquito Dunks will kill the larvae of ALL these species.
How Long Do Summit Mosquito Dunks Last?
Mosquito Dunks work for about a month. A single Mosquito Dunk can effectively treat about 100 square feet of water for 30 days or longer. While floating, a Mosquito Dunk continually releases the BTI into the water.
In cases where there is a large population of mosquito larvae and a quick kill is needed, a product called Mosquito Bits is effective. The active ingredient is Mosquito Bits is also BTI. But the BTI on each small granule of Mosquito Bits is immediately released into the water. Mosquito Bits can be particularly effective in swampy areas where the Bits can be broadcast over a large area. Mosquito Bits need to be re-applied every seven days.
How Safe are Mosquito Dunks?
Mosquito Dunks are approved for organic production and organic gardening, under National Organic Program guidelines. The EPA has registered Mosquito Dunks for use in animal watering troughs and fish habitats. Yes, a wild animal or a pet could eat a Mosquito Dunk or drink water treated with BTI. When it does, it essentially gets a large dose of protein and calcium.
The U.S. EPA doesn’t use the word “safe.” But I can. Mosquito Dunks are safe to use, because BTI only targets mosquito larvae. (Plus the larvae of fungus gnats, which are genetically very similar to mosquitoes. That’s why the BTI in Mosquito Bits kills fungus gnat larvae in potted plants.)
A 6-pack of Mosquito Dunks sells for about $13. Mosquito Dunks and Mosquito Bits are available online and at hardware stores and garden centers. For additional information visit Summit Responsible Solutions.
For your convenience, the product links in this story connect to Amazon where you can buy the products. HG&H receives a small commission from these sales.
Tutua Boshell says
I need a lot of BTI or Mosquito Dunks for my farm is Saldaña Tolima, Colombia!
phillip smith says
are they safe to use where blandings turtle live.
Randy Schultz says
Yes. Mosquito Dunks won’t hurt turtles or any other animals. The BTI in the Dunks only kill mosquito larvae.
Lori says
Is this something you would put in a pool?
Randy Schultz says
Lori–
If the swimming pool is being properly maintained (water kept clean, water treated with chlorine, etc.) you don’t need to add Mosquito Dunks. If it’s a kids’ swimming pool (filled with clear water and left out for a period of days without being used), putting a Mosquito Dunk in the water will keep it from becoming a breeding ground for mosquitoes.
Randy
Charisse Lewis says
I have used Mosquito Dunks for several years now and I can’t recommend them highly enough. They really work and they are safe for animals because I had them in my horse troughs and my horses were Not adversely affected..
Jamie says
Can these be used in bird baths? If so, what is the application?
Randy Schultz says
Jamie–
For bird baths, break up a Mosquito Dunk into halves or quarters and float a piece in the water. Dunks are harmless to birds, animals, pets, fish, and beneficial insects. The BTI in the Dunk targets ONLY mosquito larvae and nothing else!
Randy
Linda Stewart says
I get standing water in my back yard in very small places. I don’t have horse troughs or koi ponds. I however, I do breed mosquitoes in planter saucers and other small containers in the yard. Will the Mosquito Dunks “donuts” still work if broken into halves or quarters for these spaces?
Randy Schultz says
Linda–
The Dunks work great to kill mosquito larvae in standing water such as in plant saucers. As you suggested, just break up a Dunk into smaller pieces for small amounts of water.
Randy
Henry says
Will Mosquito Dunks harm honey bees?
Randy Schultz says
Henry–
No, Mosquito Dunks will not harm honey bees or any other beneficial insects. Nor will Dunks harm animals (including pets), birds, fish, or humans. The BTI in Mosquito Dunks and Mosquito Bits is harmful ONLY to mosquito larvae.
Randy Schultz