Aedes aegypti mosquito, a day biting species. Credit: CDC/James Gathany
by David Goldstein
According to weatherspark.com, the rainy season in Ventura County usually starts this week and lasts 6.6 months, peaking in February. Although Ventura County has been hot and dry recently, now is a good time to start preventing mosquito breeding, a problem usually coming in tandem with our wet season.
According to Cary Svoboda, Vector Control Program Lead with the Ventura County Environmental Health Division, small, day-biting, invasive Aedes mosquitoes were recently found in several cities in Ventura County. The problem will get much worse if we do not take precautions before the rains start.
One precaution is to be sure proper screens are attached to rain barrels that capture rainwater. A 1/16 inch mesh is necessary to keep out all mosquitoes, according to Svoboda.
Tire swings, tire sandboxes, tire obstacle courses and other reuses of tires can also pose mosquito breeding dangers. No matter how a stored tire is angled, if it is uncovered, it will collect water. Worse, when the rain is over, the tire’s curve shades collected water, preventing rapid evaporation, and the tire’s black rubber heats the water, making it even more attractive to mosquitoes. Puncturing tire walls for drainage is difficult, and because cutting tools bounce off tires, it can be dangerous, so covering tires to prevent water collection is essential, if not always practical.
Also, keep an eye on potted plants to avoid a problem my parents faced last month. Plagued by mosquitos, they called a vector control specialist who examined their backyard and found pools of water in their overgrown, root-bound, potted orchids. Roots were preventing drainage out of the bottom of the pots, so water was pooling under leafs at the top of the soil, and mosquitoes were breeding. Re-pot to avoid problems.
A similar problem with potted plants relates to over-watering. If you over-water, you can create puddles in the drainage plate under the pot.
The Vector Control Program for Ventura County, managed by the Ventura County Environmental Health Division, has a website on the topic, at www.vcrma.org/vector-control-program, which mentions other tips. For example, fill a hollow tree stump or tree hole with sand to avoid water accumulation; store wheelbarrows, small boats, children’s toys, wading pools, and empty pots upside down; and avoid accumulation of lawn cuttings or raked leaves in gutters and storm drains to ensure water flows rather than pools.
You should also stock ornamental ponds with mosquito fish, which are available free by calling 805-662-6582. Bacterial larvicide, such as MosquitoDunks, is another control measure targeting mosquito larvae.
If you see a danger on someone else’s property, the best option is to politely inform them. Another option is to contact the Ventura County Vector Control hotline at 805-658-4310. You can leave an anonymous report, including only the address of the danger, but if you also leave your name and phone number, staff can follow up with you in case they are unable to find the danger you noticed.
David Goldstein, with the Ventura County Public Works Agency, can be reached at 805-658-4312 or firstname.lastname@example.org.