Cold weather stifles mosquitoes

Cold weather stifles mosquitoes


With a cold front pushing its way through Southeast Texas on Wednesday, Oct. 16, and with cooler weather coming with it, the question arises, “Are the mosquitoes going away anytime soon?”

“Hopefully we are seeing some relief,” Jefferson County Mosquito Control District (JCMCD) Director Kevin Sexton said. “At the very beginning of the month, we had some high tides along the coast that were due to the disturbance in the Bay of Camphece. It’s flooded our marshes a little bit, so we had mosquitoes from that. This last round was due to high tides and the rain we had.”

Sexton said the county is spraying for salt marsh mosquitoes as well as rice field mosquitoes, which tend to be larger in size.

Temperature also determines the size of the mosquito, he said.

“Different times of the year, a species may be different sizes,” said Sexton, who added that a bigger mosquito doesn’t necessarily mean a bigger bite. “The cooler it is, the longer it takes them to get through their cycle from the egg to adult. Because they are growing slower and longer, it means they are getting bigger. If it is warmer, they tend to be small and hatch out a lot faster.”

Sexton said JCMCD has been spraying the entire county, covering some areas of Jefferson County three times, and that the mosquito population count is going down.

“The phone calls are starting to dwindle off, so I think we are making some headway,” he said.

Whether the mosquito activity slows down or not is really dependent on the weather, Sexton said.

“It depends how much rain we have and what the temperatures are going to be,” Sexton said. “If we have a normal fall and winter and the temperatures start falling where they should be then that should slow the mosquito activity down. Also, when you start getting these north winds, the tides are going to tend to go out instead of coming in. Once we start getting some north winds and the water temperature starts cooling off, that should help us out.”

The mosquito populations begin to die off when the area begins to see significant cold fronts on a regular basis with temperatures in the 40s, Sexton said, usually beginning in November.

Sexton said Jefferson County has not had one positive pool of mosquitoes for West Nile in 2013. According to Texas Department of State Health Services data, there has only been one reported case of West Nile in 2013, compared to 10 in 2012.

Mosquito activity all together is down from last year, he said.

“It didn’t really start picking up until September,” Sexton said. “September and thus far in October, we’ve had more mosquito activity. … We should see mosquito activity diminishing if we have a normal winter and not a mild winter.”

According to the 2014 Old Farmer’s Almanac Long-Range Weather Forecast for Texas-Oklahoma, November temperatures are expected to be 2 degrees below average across Texas and Oklahoma with winter temperatures “slightly colder than normal on average” and “participation and snowfall a bit above normal in Oklahoma and north of The Metroplex.” However, “elsewhere across Texas, temperatures will be above normal, with below-normal rainfall and snowfall.”