It’s been shown that the best way to control mosquitoes is at the larval stage—stage two of four in the mosquito life cycle.
We take a look at some of the most widely used forms of larval mosquito control and why you might want to use one.
Quick Facts
- Controlling adult mosquito populations is often difficult due to sheer numbers and the fact that they are highly mobile.
- Mosquito larvae can only survive in water, and must come to the surface to breathe air.
- Midges, small biting flies, may be confused at times with mosquitoes, since they are both tiny, bite humans, and draw blood.
Why Does it Matter?
For most of us, mosquitoes are just mildly annoying. However, in some parts of the world, mosquito-borne diseases are a public health crisis. Thankfully, in the United States, there are many wide-spread mosquito control programs in place to keep these diseases from becoming epidemics here.
Believe it or not, mosquito larvae can be found in gutters, rain barrels, puddles, catch basins—really anywhere water can pool, including tire swings and playground equipment. There could be thousands of adults that hatch in these people-dense areas.
That’s why it’s so critical to nip the mosquito life cycle in the bud and prevent the larvae from maturing into biting adults.
So how is it done? We take a look at several widely used larvicides below, in addition to a few DIY methods of larval mosquito control you can try at home.
Types of Larvicides
There are several types of larvicides available; some are only for commercial or agency use, while others are available to the public.
Most of these are liquids that are applied by using sprayers, but you can also find some of them in pellet, tablet, granule, and briquet (or briquette) forms.
The best thing about the products noted below is that, as long as they’re used in the way the product labels say, they won’t harm non-target insects, humans, animals, or the environment—just those pesky mosquito larvae!
We list some of the most common active ingredients and larvicidal products below.
Bacillus Sphaericus
This bacterium is used to kill mosquito larvae by attacking their digestive systems when they eat it. B. sphaericus typically has to be introduced into the water source the larvae live in. These bacteria are not harmful to other animals. B. sphaericus can be found in some lawn and garden centers and hardware stores.
BTI
Similar to B. sphaericus, bacillus thuringiensis israelensis (BTI) is a bacterium that’s toxic to mosquito larvae when they ingest it. It does not harm other animals. Learn more about BTI >
“Mosquito dunks” (or pucks) often contain BTI and are used to treat ponds, drainage ditches, and other areas of water that aren’t drainable and aren’t used as drinking water.
Mosquito dunks can be purchased from some home improvement stores, hardware stores, and lawn and garden centers. Learn more about mosquito dunks >
Methoprene
Methoprene is an insect growth regulator, meaning that it disrupts the mosquito’s growth cycle and prevents it from becoming an adult.
One common brand that uses methoprene is Altosid® and Altosid® Pro-G. This product comes in pellet, briquette, liquid, and granule forms, for wide applicability.
Products containing methoprene can also be purchased by individuals from hardware stores, lawn and garden stores, and some home improvement centers.
Spinosad
Interestingly, this combination of soil bacterium (spinosyn A and spinosyn D) was discovered in 1982 and found to have pest control properties. It’s toxic to insects and used on multiple pests, not just mosquitoes.
Pesticides containing spinosad are available at a wide variety of sellers, including Walmart and Amazon.com, and not just hardware stores or lawn and garden centers.
Larviciding Oils
These oils cover the water surface that larvae and pupae live in and drown them because they’re unable to break through the oil level to get air to breathe.
Mosquito Larvicide Stations
These use a combination of an insect growth regulator and a fungus harmful to mosquitoes to contaminate eggs and kill adult mosquitoes after a few days. If enough of the right adult mosquitoes are enticed into the trap, then these can be effective.
Stations are typically only used by professionals, though they may be placed in your yard by a professional pesticide company.
Other Types of Mosquito Control
Of course, there are other ways of killing mosquito larvae that don’t involve chemicals or bacteria.
One easy way to get rid of unwanted mosquito larvae is by adding mineral oil to standing water (not used for drinking). It works in the same way as larvicidal oils, drowning the larvae and pupae.
All you need is 1/4 teaspoon of mineral oil per gallon of water. You can achieve the same results by substituting vegetable oil or neem oil for the mineral oil.
You can also try the same trick using dish detergent, but you’ll only need 1/16 teaspoon per gallon of water.
A few other DIY ways to reduce larvae/adult mosquitoes include:
- Eliminating any areas of standing water (including draining birdbaths) to prevent mosquito larvae from having any place to survive.
- Regularly maintaining outdoor pools by making sure the pump is in good working order and proper levels of chlorine are used.
- Adding goldfish or mosquito fish to decorative water features, ponds, or lakes since they eat mosquito larvae.
If you’re concerned about mosquitoes in your yard, start by removing all areas of standing water you can. For the rest, your best option is to use a larvicide, and there are many effective options available!
Sources
- Environmental Protection Agency, “Controlling Mosquitoes at the Larval Stage.”
- Illinois Department of Public Health, “Mosquitoes and Disease.”
- Centers for Disease Control and Prevention, “Mosquito Control: What You Need to Know About Using Larvicides.”
- Benton County Mosquito Control District, “Mosquito Larviciding.”
- Central Mosquito Control, “Altosid®.”
- The National Center for Biotechnology Information, “Effectiveness of Autodissemination Stations Containing Pyriproxyfen in Reducing Immature Aedes Albopictus Populations.”
- SFGate, “Homemade Liquid Solution to Kill Mosquitoes.”