Abatement district launches 2 new programs to control mosquito population in Clovis

Bzzzz.

The Aedes aegypti mosquito is rearing its ugly head as the weather warms up in Clovis.

But the Consolidated Mosquito Abatement District is launching two new programs this month to control this invasive species of mosquito that was first detected in Clovis in 2013.

Aedes aegypti is different from other mosquito species because it bites during the day — causing a huge nuisance for residents in affected neighborhoods.

This mosquito is also a vector for several diseases, including dengue, chikungunya and zika viruses.

Search and destroy

The first program involves a monthly outdoor inspection and elimination of any possible mosquito habitats in a neighborhood near Ashlan and DeWolf.

This will be a bit tricky, since it requires every household in the Braden Court neighborhood — all 122 homes — to comply, said Jodi Holeman, the scientific-technical services director with the district.

“We need 100 percent cooperation, or it’s not going to work,” she said. “We’re attempting 100 percent source elimination — so the mosquitoes have nowhere to breed.”

Once a month, Abatement workers will inspect the outside of each home, including the backyard, to empty all containers holding water, drain unmanned ponds not containing mosquitofish, install screens on yard drains to prevent egg-laying mosquitoes from entering and disconnect conduits attached to rainwater spouts at ground level. At the end of the project, such spouts will be reattached.

“These are control strategies that every Clovis resident could do if they wanted to — just go around their yard regularly and look for any standing water,” Holeman said. “They should also screen every yard drain so Aedes aegypti cannot get down there. They’re very difficult to treat because they’re underground, so keeping the mosquitoes out is best.”

Through the Braden Court Project, abatement personnel will try to guarantee that every single property in the neighborhood is not producing mosquitoes, Holeman said.

“We hope it’ll be as close to a mosquito-free neighborhood as possible,” she said. “If it works, we hope this will encourage other Clovis residents to be diligent in eliminating mosquito habitats as well. Because they can do these things in their yard, but if their neighbors aren’t doing it, they’re going to have mosquitoes around.”

There are two possible outcomes to the Braden Court Project, Holeman said.

“These people are either going to have a great summer, or we’ll fail miserably, which means these mosquitoes are coming from somewhere else, somewhere we can’t find and we need to figure out where,” she said.

Sterilize the skeeters

The district’s second, simultaneous project is a mosquito release similar to one that was done last summer.

In August, mosquito abatement workers released 10,000 male mosquitoes per week in a Clovis neighborhood north of Shaw Avenue and west of Temperance Avenue.

The males, which don’t bite, acted as double agents, working against their own kind. They were dusted with insecticide and then released to mate with female mosquitoes and deposit insecticide into containers of water where the females laid their eggs.

It took a while to tell if the Auto-Dissemination Augmented by Males (ADAM) project had worked because the insecticide didn’t kill adult mosquitoes; it prevented eggs and larvae from maturing into adults.

ADAM saw some success.

It was the first time male mosquitoes survived being shipped in large quantities to an abatement district, Holeman said. The insecticide-laden mosquitoes were raised in a University of Kentucky laboratory and then shipped to Clovis in cardboard tubes.

Insecticide also successfully made its way into the water sources set out in the Clovis neighborhood.

However, the results weren’t as significant as the district would’ve liked.

“We know we were killing some mosquitoes, but it was not enough for residents to say that they noticed a reduction in the mosquito population,” Holeman said. “We need to have such an impact that people notice there are fewer mosquitoes.”

But the district isn’t giving up.

“We still think it is a great idea; it just wasn’t effective as we needed it to be,” Holeman said. “So now we’re going to do something similar, but at the same time, completely different.”

Once again, male mosquitoes will be released into a Clovis neighborhood, but this time they’ll have bacteria, called Wolbachia, instead of insecticide.

“Wolbachia are common bacteria that you can find in a lot of insects, like dragonflies, butterflies, mosquito species and flies,” she said. “The bacteria alters an insect’s ability to reproduce.”

This time around, the district will release 40,000 Wolbachia-laden male mosquitoes per week — from May through October — at 20 sites within a neighborhood west of Dewolf Avenue between Barstow Avenue and Shaw Avenue, Holeman said.

“When they mate with the wild female mosquitoes in Clovis, the hope is that the Wolbachia will make it so that the offspring are not viable. The eggs won’t develop,” she said.

This Sterile Insect Technique has been approved by the California Department of Public Health, the state Department of Pesticide Regulations and the federal Environmental Protection Agency, Holeman said.

This story was originally published April 29, 2016 at 10:23 AM with the headline "Abatement district launches 2 new programs to control mosquito population in Clovis."