Trillions of Cicadas to emerge in the US after 17 years of hibernation

The bugs are commonly, but incorrectly known as "locusts," and will appear for the first time since they underwent hibernation in 2004 throughout more than 15 US states. 

After nearly two decades underground in an immature state eating tree root sap, the bugs will crawl out in mid-May to late June when soil hits 17 degrees celsius, likely after the first warm rain. 

During their short time alive, Cicadas will need to find a mate to reproduce, escape predators intent on eating them, and avoid an STD-like parasitic fungus that turns them into zombies and controls their actions. 

The precise cicadas emerge is largely dependent on the weather, but if you leave nearby, you’ll know when they do. The first thing immature cicadas do when they're out of the ground is climb the nearest vertical surface, and shed their skin as they transform into their adult form.

Noisy announcement

After moulting, they announce their readiness to mate with deafening mating calls. In a chorus, their calls can exceed 100 decibels, enough to drown out a car blasting its stereo at maximum volume or drown out a passing airplane. 

To put that into context, normal human conversation is 60 decibels on average. Some cicadas such as the Greengrocer, native to Australia, can reach 120 decibels. That’s as loud as industrial or construction equipment, or standing next to emergency sirens. It’s also as loud you can get without injuring human ears, which occurs at 130 decibels.

The cicada makes its nose using a ‘tymbal’, which works like a drum. The stretched skin of this natural drum vibrates quickly through muscle movement, which is further amplified with a hollow abdomen.

Depending on their brood, cicadas can remain in hibernation for 13 or 17 years.

"Densities can be as great as 1.5 million per acre. So, between Georgia and New York there will surely be trillions emerging," says Michael J. Raupp, professor of entomology at the University of Maryland speaking to Newsweek.

After mating, the newly born brood will fall to the ground, hatch and burrow to begin the next 17-year hibernation.

Historical Symbolism

Historically appreciated by East and West, cicadas have an iconic shared cultural story with human beings. 

The Greeks thought the “tettix” was carefree and harmless. The Chinese, thought the “tchen” was noble, but humble.

Greek literature describes their song as “sweet”. In one Greek legend, the cicada filled in for a missing musical note, when a string broke on a musician’s instrument. Most importantly, the cicadas’ noise heralds the arrival of summer and heat. 

China’s ancient Tang dynasty (618 to 906 AD) made it practice to catch and sell caged pet cicadas to enjoy their song. They also inspired jewellery. 

During the Chinese Han Dynasty, (206 BC to 220 AD), carved jade cicadas were symbolically placed in the mouths of the dead, because of their ability to resurrect themselves. Greek nobles would also wear gold cicadas, as an affectation of their ties to Athens.

While no one is likely to wear them anymore, cicadas may still announce the arrival of a summer that’s hopefully better than the one we got in 2020 during the height of the global covid-19 pandemic.