Preventing Mosquitoes in Your Backyard

Simple tasks done on a regular basis will help protect you around your property against mosquitoes.

Did you know that most mosquitoes lay "egg rafts" and that each one can contain between 100 to 400 eggs?

It only takes mosquitoes approximately seven days to go from egg to adult mosquito. Therefore, here are some easy steps to help control mosquitoes in your backyard. Every week, dump and scrub containers that hold standing water. Keep rain gutters free of debris, keep decorative fountains operational or drain the water, change water in animal watering dishes and bird baths often. 

Standing water locations around the home.

Ornamental Ponds

Stock with mosquitofish. Add goldfish for looks if desired. Avoid spraying with garden insect sprays. Remove leaves and thin out pond lilies. Keep water level up. Screen inlet of recirculation pump. Chlorine kills fish-- transfer fish to glass bowl when cleaning pond. If pond is no longer desired, break holes in bottom and fill with dirt or sand.

Concrete or Plastic Swimming Pools

Operate filter and skimmer everyday to remove mosquito egg rafts and larvae. Provide drainage for filter and pump sumps. Chlorine will NOT kill mosquito larvae. If pool cover is used, keep it tightly sealed. Remove rainwater from top of pool cover. Stock unused or "out-of-order" pools with mosquitofish. Report neglected neighborhood pools anonymously to the District. Call the District at (209) 982-4675

Boats, Kayaks & Canoes

Prevent accumulation of bilge water and rain water. Store small boats, kayaks and canoes upside down or cover to keep out the rain and water from sprinklers.

Other kinds of Containers

Remove and dispose of all unused containers that will collect rain or water from sprinklers.

  • Cans
  • Jars
  • Barrels
  • Old Tires
  • Buckets
  • Flower pots
  • Old tires
  • Rain Barrels/drums should have tight fitting small gauge screen to prevent mosquito access.
  • Toys.

Home gardeners rooting plant cuttings in vases, buckets, etc. should change water every week. Usable containers should be stored upside down.

Protect Yourself

  • Cover up: When practical, wear long sleeves and pants when outdoors
  • Screens: Make sure doors and windows have screens that fit tightly and do not have holes
  • Use insect repellent: Apply repellent with active ingredients DEET, picaridin, IR3535, or oil of lemon eucalyptus to exposed skin and/or clothing (as directed on the product label)

For additional repellent information, follow this link to Centers for Disease Control and Prevention

Call San Joaquin County Mosquito and Vector Control District for additional information or to request service at (209) 982-4675 or 1-800-300-4675.


When dealing with West Nile virus, prevention is your best bet. Avoiding mosquito bites reduces your risk of getting this disease, along with others that mosquitoes can carry. Take the commonsense steps below to reduce your risk:

  • avoid mosquito bites and use insect repellent;
  • clean out standing water from the places where you work and play;
  • Follow the four "D's" listed below;
  • work with your local mosquito control to stop mosquito development.

1. Defending Yourself Against Mosquitoes - The 4 D's

Drain standing water around the house weekly since it's where mosquitoes lay eggs, including: tires, cans, flowerpots, clogged rain gutters, rain barrels, toys, puddles and even unused fountains.

Dusk & Dawn
Dusk and dawn are when mosquitoes that carry the virus are most active, so limit outdoor activities or take precautions to prevent mosquito bites.

Deet is an effective ingredient to look for in insect repellents.  Always follow label instructions carefully.

Dress in long sleeves and pants during dawn and dusk or in areas where mosquitoes are active.

2. Avoid Mosquito Bites

Apply Insect Repellent Containing DEET (Look for: N,N-diethyl-meta-toluamide )
Apply to exposed skin when you go outdoors. Even a short time being outdoors can be long enough to get a mosquito bite. For details on when and how to apply repellent, see Mosquito Repellent.

Clothing Can Help Reduce Mosquito Bites
When possible, wear long-sleeves, long pants and socks when outdoors. Mosquitoes may bite through thin double layers of clothing are even better.

Get double protection: wear long sleeves during peak mosquito biting hours, and spray DEET repellent directly onto your clothes.

Be Aware of Peak Mosquito Hours
The hours from dusk to dawn are peak mosquito biting times for many species of mosquitoes. Take extra care to use repellent and protective clothing during evening and early morning hours. Consider avoiding outdoor activities during these times.

3. Mosquito-Proof Your Home

Drain Standing Water (View Home)
Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to develop by getting rid of items that hold water.

Install or Repair Screens
Some mosquitoes like to come indoors. Keep them outside by having well-fitting screens on both windows and doors. Offer to help neighbors whose screens might be in bad shape.  

4. Help Your Community

Report Dead Birds to Local Authorities
Dead birds may be a sign that West Nile virus is circulating between birds and the mosquitoes in an area. Over 225 species of birds are known to have been infected with West Nile virus, though not all infected birds will die. It's important to remember that birds die from many other causes besides West Nile virus.

By reporting dead birds to toll free hotline 1-877-968-2473. You can play an important role in monitoring West Nile virus. Check the Identify and Report Dead Birds page to find information about reporting dead birds in your area.

Mosquito Control Programs
To find your local mosquito control agency click here. The Mosquito and Vector Control Association of California (MVCAC) holds a wealth of knowledge on control and surveillance in California. More questions about mosquito control? A source for information about pesticides and repellents is the National Pesticide Information Center, which also operates a toll-free information line: 1-800-858-7378 (check their Web site for hours).

Clean Up
Mosquito breeding sites can be anywhere. Neighborhood clean up days can be organized by civic or youth organizations to pick up containers from vacant lots and parks, and to encourage people to keep their yards free of standing water. Mosquitoes don't care about fences, so it's important to control breeding sites throughout the neighborhood.

West Nile Virus and
Dead Bird Hotline

(877) 968-BIRD (2473)

or online at

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