Monsoon Storms Bring An Increase in Arizona Mosquito Population

After the much-needed monsoon showers and enjoyable cooler weather, there is a potential for an increase in undesirable pests.

Maricopa County Vector Control is expecting the mosquito population to grow after the serious storms blanketed rain across most of the Valley last week.

Vector Control, which is within the Environmental Services Department, sets 823 traps around the Valley each week, to monitor for mosquitoes and know where the problem areas exist. “Usually the east side, Gilbert, Chandler area has the majority of mosquito issues that we find but this rain–I think pretty much the whole county got rain this time so we’re expecting to see problems throughout the county,” said James Will, the managing supervisor of Vector Control.

Will says for the last two years, the “nonsoon” reduced the mosquito population in the valley.  “Where we used to see three, four hundred mosquitos and we’d have a positive sample, now we have four, five mosquitoes in a positive sample, so the numbers have gone way down,” Will explained.

With the floodwaters from the recent rainstorms, Vector Control anticipates a drastic increase in mosquitoes that specifically breed in floodwaters. “They’ll come out in the thousands and thousands as they hatch, but we’re not worried about disease with them, but they’re a nuisance and they’re really ferocious biters,” Will said.

The other worrisome mosquitoes are the culex mosquitoes. They tend to bite at night time and carry diseases.

The third concerned type is aedes aegypti mosquitoes that breed in containers in people’s backyards. With all this rain, containers sitting around fill up with water and there will be an increase in those types as well.

It is recommended that residents with containers that contain standing water surrounding their yard should empty containers at least once a week. The containers should also be wiped down completely.

“The mosquitoes lay their eggs in the water and if you don’t rinse out the eggs, when you fill it back up with water, you’re basically just filling it up to let the eggs hatch,” said Will.

Not a lot can be done about the floodwaters except making an effort to get the low-lying areas to dry up as quickly as possible.

“For anybody that has low-lying areas around their house, fill them in with either rocks or dirt or something that can keep that water and make it drain faster,” Will said.

Peak mosquito season in Arizona lasts through November but starts up quickly again in the spring.