Why this summer's cicadas are noisier than usual

Buzzing cicadas, crickets and katydids are normal sounds of summer, but lately, they've been awfully loud.

Suburban bug experts say the singing bugs are unusually noisy this summer, and the hot, wet weather's to blame. The excessive heat and moisture is prompting male cicadas, crickets and katydids to “sing” their mating calls louder and more frequently.

“It's perfect weather for courtship. What you're hearing are guys who are crazy in love. They're singing like Mick Jagger and doing all they can to get a lady friend,” says Valerie Blaine, the Kane County Forest Preserve District's nature program manager and a Daily Herald Neighbor section columnist. “It does indeed sound like there's a tremendous amount. Anywhere there's trees, it's been loud.”

Cicadas are noisiest during the day, and the crickets and katydids take over in the evening. The early evening is the loudest time because of the overlap.

“It's cool because you'll hear the cicadas simmer down as the katydids and crickets rev up,” Blaine said.

Whether they sing, sting or just flutter around, it's been a buggy summer overall. This summer's heat and rain has led to a population boom for most bug species, especially mosquitoes.

The wettest July on record has triggered what the Northwest Mosquito Abatement District calls a “severe mosquito problem,” which has led to nightly sprayings. It's also caused more flowers and plants to bloom, bringing out more bees and wasps.

“Insects are kind of solar-powered, so if the sun is shining and it's hot, they are going to be more active,” said ecologist Tom Velat, of the DuPage County Forest Preserve District.

Devin Kraftka, an assistant entomologist at the Morton Arboretum in Lisle, said she's seen more butterflies, grasshoppers and lightning bugs.

For the most part, there's no harm in having all of these extra bugs flying around the suburbs.

The cicadas we're hearing are known as the “dog days cicadas” because they come out in the dog days of summer — in late July and August, says entomologist Phil Nixon, with the University of Illinois extension in Champaign. “When your nights or evenings are warmer, they're going to be more active and do more singing,” he said. “That evening time span has been pretty consistently in the low 80s or upper 70s, which is ideal temperatures for most insects. Acoustic-wise, it may be such that higher humidities help the sound resonate more.” The dog days cicadas are not as loud as the periodical 17-year cicadas, which Blaine says can hit decibel levels that exceed the sound of a lawn mower.

People who are more annoyed than charmed by the summer bug sounds can take heed: when the temperatures cool down, the “singing” will stop.

“Enjoy the music,” Blaine said. “It's a wonderful sound of summer. And it's something we don't hear when the cold winter is back.”