As cold-blooded mosquitoes begin hibernating for winter, the city’s contractor for insect control will be slowing down, as well.

Brandon Cobb, with Vector Disease Control International, said mosquito population numbers began dropping around the end of August and into mid-September, as expected.

Recent rain has been a help and a hindrance, he said.

“We can’t go out there and spray when it rains, of course, but the cooler weather is also keeping the mosquitoes down,” he said. “I’m hoping that through the end of November it’s just going to keep getting cooler, or stay cool at least. We’re still spraying every single night through the end of October, rain permitting, of course.”

They’ll do two runs in one night to make up for any rainouts.

Cobb plans for Vector to stop spraying by the end of the month, when mosquitoes are beginning their hibernation period. That’s based on weather and trap populations, he said.

Mosquitoes prefer temperatures over 80 degrees and at temperatures less than 50 degrees, the insects shut down for the winter. Cobb said some mosquitoes, that he calls scouts, may come out on warmer days during the winter thinking it could be spring, but then go back into hibernation. The Environmental Protection Agency doesn’t allow spraying for mosquitoes is the temperature outside is under 50 degrees and mosquitoes die or go into deep hibernation at 40 degrees and below, Cobb said.

Ward 1 Alderman Dorsey Cameron questioned what VDCI does from December through March.

“We don’t really have a shut-down. The mosquito season gets to a point that the mosquito population is so low that spraying for them doesn’t do any good,” he said.

However, they’re on call and ready even in the off-months.

“There may be a few mosquitoes out on warm days, but you’re not going to see the numbers that you need us out spraying the neighborhood. But if you do, we’re a phone call away,” he said.

Employees do full maintenance on trucks and sprayers during their down time.

Vector was awarded the city’s contract for mosquito spraying in June 2017.