Flood waters, warmer temps may bring more mosquitoes
By Dan Moran Sun-Times Mediaemail@example.com April 29, 2013 4:30PM
Recent flooding has brought the area some of the highest levels of mosquitos in 20 years.
Updated: June 1, 2013 6:33AM
Just as some area residents clean up from flooding because of record rainfall, they could soon be rocked with another problem — hungry floodwater mosquitoes.
“We should be seeing an emergence of floodwater mosquitoes within the next seven to 10 days,” said Laura McGowan, a spokeswoman for Roselle-based Clarke, an environmental company that manages mosquito abatement programs for multiple communities in Cook, DuPage, Kane, McHenry and Lake counties.
Floodwater mosquitoes are known as “nuisance mosquitoes, (because) they tend to be aggressive biters and they can be very nasty,” McGowan said.
But they are not to be confused with the Culex genus of the pests, which carry the potentially lethal West Nile virus.
“The good news is (floodwater mosquitoes) are not good vectors for disease, so they are not known for carrying West Nile,” McGowan said. “It’s possible, it’s just very unlikely.”
Culex mosquitoes emerge from the hot, dry weather that finds insects and birds — the host carriers of West Nile — converging around the same limited supplies of water. That has not been the problem in and around Chicago this April, with O’Hare International Airport logging a record 8.6 inches of rain and both the Des Plaines and Fox rivers washing well out of their banks.
According to McGowan, floodwater mosquitoes “can lay eggs that literally last for years in grass, and when they’re flooded, you will get a nasty outbreak of nuisance mosquitoes. (So) we’re going to see an emergence from these hatch-offs in the next few weeks.”
Sure enough, there is even more rain in the forecast for later this week, but McGowan pointed to another weather feature that could slow mosquitoes: cooler temperatures.
“We’ve been up and down with the temperatures, and mosquitoes like it hot,” she said. “It’s supposed to cool down this week, and that could help suppress the hatch-off and make them less active. Temperatures will play a big role in how aggressive they are, because mosquitoes start slowing down when it’s in the 50s.”
Eventually, of course, the mercury will turn spring into summer — and slapping season will begin.
“Mosquitoes breed every five to seven days, so we can see (emerging hatches) before Memorial Day,” McGowan said. “Some people say April showers bring May flowers — we say April showers bring May mosquitoes.”