Although the great cicada emergence of 2024 may be coming to an end, the “summer of the cicadas” is far from over and the next cycle could look a little different.
This is because another emergence is on the horizon.
The season began with the emergence of not one but two large periodic broods of cicadas, which have not emerged simultaneously in more than 220 years.
But while the two periodic broods of cicadas emerge every 13 or 17 years, there is also one annual cicada that emerges each summer: the annual “dog day” cicadas of Illinois.
“Not only do we get cicadas every 17 years,” said Allen Lawrance, associate curator of entomology at the Peggy Notebaert Nature Museum in Chicago. “We get them every year. They’re our annual cicadas. They’re bigger and greener.”
There are other differences between Illinois periodical cicadas and annual cicadas, Lawrance said.
“Periodic cicadas are smaller than our annual cicadas,” Lawrance said. “You can see their bodies are a little thinner, a little more cylindrical.”
Lawrance noted that annual cicadas, which emerge each summer in Illinois, are more “robust” and generally noisier than periodical cicadas. But there is power in numbers, Lawrance said.
“(Periodical cicadas) are not as loud individually, but because there are so many more of them, their song is louder overall,” Lawrance said, as billions of periodicals from Broods XIII and XIX are expected in the Illinois.
When will “Dog Day” cicadas come out in Illinois?
Illinois’ annual cicadas can be expected to emerge in July, August and September, according to a University of Illinois Extension article.
“It typically takes 2 to 5 years to complete their development and their generations overlap and are not synchronized,” the article states. “On the other hand, periodical cicadas take 13 or 17 years to complete their development from egg to adult, and they emerge en masse in the spring.”
While periodical cicadas begin to emerge once soil temperatures reach 64 degrees, “dog day” cicadas emerge from the ground “during the heat of summer, or during the dog days of summer.” , explains the article.
The periodical cicadas will be gone by the time the annual cicadas appear, Lawrance said. Yet in Illinois, this spring and summer could look like cicada season.
“There’s really no way to escape them,” Lawrance said, especially on and around trees, where “heaps” of cicada shells are expected after the insects feast on the liquid from the branches and woody shrubs.
“You’re just going to see them flying around, hanging out in the trees,” Lawrance said. “And you will hear them wherever you go.”
What else is coming?
Beyond diurnal cicadas, there also remains the question of periodical cicada eggs.
Hatching occurs between six and 10 weeks after the eggs are laid, and while it’s rare to get a glimpse of this time, Kritsky said when conditions are right, this time could be visible in the area. from Chicago.
“If the sun is at the right angle, people have actually seen the nymphs fall to the ground,” Kritsky said, pointing out that the sun should be behind the tree where the eggs hatch, “illuminating them as they fall.” .
Trees in areas that have seen large emergences could have up to 40,000 eggs waiting to hatch, he added.
NBC Chicago
