Mosquito Abatement Tips for San Diego County

by Kim Schultz, UC Master Gardener

 

The high-pitched “Bzzzzzzzzzzzz,” whine of a mosquito may be one of the least favorite sounds of summer. In San Diego County, mosquito season runs from April to October but long summer days may be when mosquitoes are most noticed by residents. During hot weather, a mosquito can go from an egg to a mature (blood-drinking) adult in one week.

Mosquitoes are more than simply annoying. In San Diego County, there are 28 types of mosquitoes; nine of those types can transmit diseases to humans, and  mosquitoes have been documented to spread both Dengue and West Nile virus to people. Here. Invasive Aedes mosquitoes can spread heartworms in dogs. These diseases can cause serious complications and even death, so it’s important to minimize exposure to mosquito bites and prevent mosquito breeding.

Fight the Bite

When trying to avoid mosquito bites, long sleeves, pants, and socks that fight those pesky, invasive ankle-biting Aedes mosquitoes among other types are always the first best method, but when summer temperatures rise, other mosquito-thwarting techniques come into play. Check screens on windows and doors for holes and gaps to keep mosquitoes out of your home. When you’re outside, insect repellents with EPA-approved active ingredients are your best bet, as long as they are used in accordance with the directions on the label. EPA-approved active ingredients include DEET, picaridin, oil of lemon eucalyptus, Para-menthane-diol, 2-undecanone, or IR3535. For more information, see San Diego County’s Fight the Bite page: https://www.sandiegocounty.gov/content/sdc/deh/pests/mosquitoes.html 

Prevent Mosquitoes from Breeding

Mosquitoes breed in stagnant water, and they don’t need much standing water to make a lot of mosquitoes; a bottle cap or plant saucer could provide enough space. Double-check all potential spots for standing water, everything from rain gutters, rain barrels, and children’s toys to old tires, abandoned water bottles, and plant saucers, inside of your home and out. Here’s a great video resource from the County of San Diego sharing many of the places standing water can hide in your home or garden:https://www.sandiegocounty.gov/content/sdc/deh/pests/wnv/prevention.html 

If an unusual number of mosquitoes persists after checking all potential standing water sources, request an educational mosquito inspection by contacting the San Diego County Department of Environmental Health and Quality’s Vector Control Program at (858) 694-2888. If there’s standing water like horse troughs, ponds, and fountains, pick up mosquito larvicides (sometimes referred to as mosquito dunks or mosquito bits) from a nursery, hardware or home improvement store, or pick up mosquito fish for free from the Vector Control program at locations throughout the county: https://www.sandiegocounty.gov/content/sdc/deh/pests/mosquitoes/mosquito_fish/mosquito_fish_locations.html 

Mosquito Bucket Challenge

You may have seen the Mosquito Bucket Challenge on social media, where folks put standing water in a 5-gallon bucket with a mosquito larvicide, then attach screens or other barriers over the top of the bucket which allow mosquitoes to get to the water while preventing entry by small animals who may not be able to get back out (including small children). There are variations where folks add sticks, plants, or other material to the bucket, but the goal is to create an environment conducive to mosquito breeding while applying a larvicide to neutralize the mosquito’s ability to reproduce. While the concept works in theory, there isn’t any UC research-based evidence at this time to show the efficacy of this method. Keep in mind that if you create a mosquito breeding ground and forget to reapply the larvicide, the effect will be a spectacular backfire: Mosquitoes mature so quickly that forgetting to add the dunks will create swarms of hungry mosquitoes. Best research-based Integrated Pest Management (IPM) practices recommend eliminating standing water wherever possible and using mosquito larvicide in standing water that can’t be eliminated or minimized, such as horse troughs and ponds.

Report Potential Mosquito Activity

Mosquitoes travel, so even if you’ve eliminated all the risks in and around your own home, you may still be bothered by mosquitoes from your area. If there is an unmaintained, green, or otherwise neglected swimming pool or pond in your neighborhood, report it to the County Vector Control Program by submitting a request here: https://www.sandiegocounty.gov/content/sdc/deh/pests/InspectionRequest.html 

Another helpful route that you may not have considered is reporting any dead birds you find. One of the ways scientists track mosquito-borne diseases is by tracking bird deaths. Crows, ravens, jays, hawks, owls, and falcons can all contract diseases like West Nile virus from infected mosquito bites. If you find one of these types of dead birds, do not touch it with your bare hands, but report the dead bird to the County Vector Control program by calling (858) 694-2888 Mon-Fri 8:00 am - 5:00 pm or (858) 505-6657 on weekends, holidays, or outside business hours, or emailing them at vector@sdcounty.ca.gov during business hours, 8am-5pm, M-F only. More information is here: https://www.sandiegocounty.gov/content/sdc/deh/pests/wnv/report_dead_birds.html 

Conclusion

Mosquitoes may be ubiquitous in the summer, but knowing what to do to minimize their effects and breeding is the first step towards diminishing their impact. Once you know what to look for, it’s simple to eliminate or neutralize mosquito breeding grounds. Protect yourself and your family with appropriate clothing and mosquito repellents to make sure you can enjoy all the outdoor summer activities that San Diego offers without getting those annoying mosquito bites.