Just when you thought it was safe to go outside, peak mosquito season arrived.
Mosquito swatting is now in full force just as an off-the-charts season for gnats has finally tapered. That may not seem fair, but the good news — if there is any when it comes to bloodsucking bugs — is that one of the wettest seasons on record here in the Twin Cities isn’t pushing the mosquito population into super overdrive.
“It’s a challenging year,” said Mike McLean, spokesman for the Metropolitan Mosquito Control District. “But it’s not off the scales. … We’re trying to stay ahead of them.”
The control district has already treated about 100,000 acres to tamp down the mosquitoes. Before the July 4th holiday, it did its best to treat areas where the inland floodwater mosquito (Aedes vexans) would emerge. The species is abundant, fairly aggressive and loves to bite humans, McLean said. “They’re good at driving people crazy.”
On the bright side, they don’t live very long and their populations should be waning, he said. Unfortunately, Minnesota has about 50 varieties of mosquitoes. Most don’t prefer humans as their first meal choice, but that’s little consolation when you’re being swarmed and bitten.
Now comes the cattail mosquito (Coquillettidia perturbans), a large and aggressive mosquito that overwinters under ice and emerges whether it’s a wet year or dry one.
Over the last couple of years, wet seasons have expanded the habitat for those mosquitoes and the control district has done what it can to curb the population, McLean said. As the water table has risen, the control district is treating more areas — up from about 600 to 700 acres a few years ago to a few thousand acres today, McLean said.
“We try to lower the background level of human-biting mosquitoes where the average person can tolerate it,” he said. “It’s not like we can eradicate mosquitoes, but we try to give people the best shot of doing something on their own whether it be with a mosquito repellent or a citronella candle. Our goal is to make sure the mosquito population is not off the charts.”
But that doesn’t mean people don’t complain. Over the last month, the control district has received nearly 850 calls ranging from people who are merely annoyed to those who pinpoint mosquito breeding areas that they want treated, McLean said. Those numbers are on par for a wet year, he said.
The Twin Cities so far has experienced the ninth wettest year since weather-keeping records began in 1871, said Tyler Hasenstein, meteorologist with the National Weather Service in Chanhassen. March and April were wetter than usual, but May was a real soaker, with 6.68 inches of rain — twice the normal amount, Hasenstein said.
As usual, the mosquito population begins to drop by late July, McLean said. Unfortunately, people often get lax in protecting themselves at a time when mosquitoes are more likely to carry disease, such as West Nile.
“This is the time when you can’t let your guard down,” he said.