Swatting away more mosquitoes lately? Michigan’s heat wave may be to blame

• Recent heat and rain have combined to send Michiganders swatting mosquitoes and reaching for bug spray
• Mosquitoes are usually the most active during July and August, but climate change can lengthen mosquito season
• Wear long sleeves, use bug spray, and get rid of standing water to avoid bites 

This holiday weekend, the air will be full of more than just fireworks. Michigan’s infamous insect, the mosquito, is out in full force, partially due to the record-breaking heat wave in Michigan and the eastern U.S. last week. 

Most of the state spent the last week under an extreme heat advisory with some areas experiencing a heat index, or “feels like” temperature, of over 100 degrees Fahrenheit. 

Mosquitoes thrive in these higher temperatures, said David Lowenstein, a consumer horticulture extension educator at Michigan State University.

“On average, it takes about two weeks for mosquitoes to complete their life cycle,” Lowenstein told Bridge Michigan. “But with higher temperatures, it can be as little as 7 to 10 days that they can cycle through egg to adults. So certainly that can lead to mosquitoes being more common because they're reproducing quicker.” 

Recent rainfall in many areas of the state can also provide the perfect breeding grounds for the insect in standing pools of water.

“Mosquitoes require standing water to complete their life cycle, so the larva develop within water, and we've had quite a bit of rain across parts of the state over the last few weeks,” Lowenstein said.

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The Michigan Department of Health and Human Services recommends eliminating standing pools of water such as kiddie pools, bird baths, buckets and old tires to reduce the number of mosquitoes. 

Michigan is home to about 70 different species of mosquitoes, some of which  carry the West Nile Virus. Although most people who become infected don’t show symptoms, people over 60 are at a higher risk of severe symptoms. These can include headache, high fever, neck stiffness, body aches, vomiting and rash.

West Nile Virus tends to show up in July or August in Michigan, Lowenstein said. Besides getting rid of standing water, residents are encouraged to apply a DEET-based bug spray and wear long sleeves around dusk or dawn to reduce mosquito bites. When inside, install or repair window screens to prevent mosquitos from coming inside the home. 

Mosquito seasons like these could become more common with climate change, according to Lowenstein. Although mosquitoes are most active in July and August, the insects come out when the temperature is over 50 degrees, and with warming temperatures, that means they can appear earlier in the spring and later in the fall.

“The greatest impacts of climate change would be lengthening the season,” Lowenstein said. “If the season started warm earlier, and we keep temperatures in the upper 80s, 90s, that means that mosquitoes can complete their life cycle faster, which could mean more generations of mosquitoes throughout the season.”