Mosquitoes – Yard Protection

Mosquitoes need standing water to breed. They do not need a lot of water, but they need about 10-14 days to go from egg to adult mosquito. And when mosquito pupae hatch to adults, they actually have to stand on the water surface and wait for their wings to dry and harden before they can fly[1]^,[2].

The good news is…

If you have puddles that dry in a week’s time or less, mosquito eggs and larvae will not survive to adulthood[3].

Chlorine is toxic to mosquitoes, so a properly maintained swimming pool will not be a breeding ground.

Ponds/waterfall yard features

Adding fish to your pond will provide a natural predator for mosquitoes and larvae. Also, anything that disrupts the surface tension of water will help reduce successful mosquito hatching, achieved by aeration in water fountains or ponds[4]^,5.

Check your yard for items that hold water

Tarps over yard furniture or equipment can sag and hold water for extended periods.

Unused flower pots or containers– overturn them or keep them in a shed so they can’t fill with rainwater. Even some plants and tree holes can hold water for extended periods of time.

Bird Baths

If you clean your bird bath about once a week, you will get rid of eggs and larvae before they can ever become adult mosquitoes. Just completely empty the bath and rinse it out with a garden hose[5].

Corrugated drain pipe is a favorite breeding spot for mosquitoes[6]. Check your drainspouts, they probably drain into black corrugated drain pipe that lies under your yard. Bacillus thuringiensis var. israelensis (Bti) – a naturally occurring soil bacteria that selectively targets mosquitoes is the preferred larvicide[7],[8]. It is non toxic, and environmentally safe. “Mosquito Dunks” is a readily available brand of Bti that is donut-shaped; this enables you to tie a string around the dunk and drop it into a drain pipe, then stake or tie it so it will not wash out of the other end.

Marshy areas

Bti (“Mosquito Dunks”) can be used in marshy areas of your yard, or in streams that cross your yard. According to Joshua Smith, a biologist with the Fairfax County Health Department’s Disease Carrying Insect Program, you can use Bti anywhere on your property, even if your yard backs up to park land or streams, or if water run-off from your land empties into County parks or streams. The Park Authority does not use any larvicides in any County parkland. Fairfax does use Bti in catch basins throughout the county.

Most permanent bodies of water, such as lakes, creeks and streams have established eco-systems that include the mosquitoes’ natural predators, such as fish, dragonflies and damsel flies.

Rain cisterns or catch basins – also use Mosquito Dunks.

For other yard protective measures, see Mosquito Control Product Recommendations

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[1]Los Angeles West Vector & Vector Borne Disease Control District. Mosquito Ecology. Retrieved from http://www.lawestvector.org/mosquitobiology.htm.

[2] Dallas Ft. Worth Pest Control. Mister Mosquito. Retrieved from www.dfwpest.com/mosquitoinfo.htm

[3] Virginia Department of Health. Frequently Asked Questions About Mosquitoes. Retrieved from http://www.vdh.virginia.gov/epidemiology/DZEE/Vectorborne/mosquitofaq.htm

[4]Ladd, B., Frankenberger, J. Management of Ponds, Wetlands, and Other Water Reservoirs to Minimize Mosquitoes. Retrieved from http://www.ces.purdue.edu/waterquality/resources/mosquitoes1.htm

[5] “Mosquito Hygiene” throughout the Life Cycle of Culex Mosquitoes, 2002, Cornell University Center for the Environment, retrieved from http://cfe/cornell.edu/ERAP

[6] Fairfax County Health Department, 2008. Protecting Yourself From Disease Carrying Insects. Fairfax County, VA.

[7] Lacey, L.A., 2007. Bacillus Thuringiensis Serovariety Israelensis and Bacillus Sphaericus for Mosquito Control. Journal of the American Mosquito Control Associaion, 23(2), 133-163.

[8] Fairfax County Health Department, 2008. West Nile Virus Larvicide. Retrieved from http://www.fairfaxcounty.gov/hd/westnile/wnlarvicide.htm.