Spray on the repellent and wear light-colored clothing if you’re headed outdoors this weekend because mosquito larvae will be hatching and the newborns will be looking for lunch.
Recent heavy rains combined with warm weather will bring out a healthy brood of biting pests that are just itching to fly, said Mike McLean, a spokesman for the Metropolitan Mosquito Control District.
“We will see more numbers of them than we have so far,” McLean said. “We are on the cusp of them coming out.”
The insects lay their eggs in water and there has been plenty of that in recent days to generate a bumper crop.
The Metropolitan Mosquito Control District has been doing its part to stay ahead of the expected population burst by spreading granular pellets laced with a bacterium called Bacillus Thuringiensis Israelensis, or BTI for short. Larvae ingest the pellets that feature a texture resembling a Grape-Nuts flake, killing them on the spot. BTI, however, won’t kill any other bugs and it’s not lethal to humans, McLean said.
The district has used six helicopters to drop BTI over swamps, marshes and other areas prone to mosquito development. The district has treated more than 40,000 acres in the seven-county metro area in the past few days with airdrops and crews on the ground.
But larvae feed on the bacterium only while they are small and still in the water. Once big enough to fly they stop eating it and come after us, McLean said.
It’s kind of like fighting crabgrass, he said. It takes only seven to eight days for larvae to grow big enough to fly, so the window of opportunity to catch them is small. The treatment has to be put down at just the right time.
“We’ve been going overtime since the rain stopped,” McLean said. “Time will tell how many we have gotten.”
And if it rains again, as it might Monday and Tuesday, the district will have to retrace its steps. BTI breaks down and a new dose would need to be spread to keep the next batch from hatching.
While the agency is doing what it can, humans can lend a hand by emptying trash bins, old tires and any water-filled receptacles that turn into breeding grounds.
McLean also recommended wearing light-colored clothing because mosquitoes are attracted to dark shapes and colors. And go indoors at dusk when mosquitoes tend to be most active. Short of that, you may be doing a lot of slapping and swatting.
The buzzing pests are generally harmless at this time of year, bringing only that irritating itching to those they bite. As the summer goes, the on the risk of contracting a mosquito-borne illness increases, McLean said.
The number of adult mosquitoes generally drops by August, but those still alive may have picked up a disease from another animal or source and can spread it to animals or humans. Late summer also is the time of year people tend to stop putting on bug spray.
“They let their guard down,” he said