On April 16th, it was reported that some parts of the United States are set to experience the largest cicada emergence in 221 years. During this event, trillions of cicadas will emerge from underground to engage in their unusually noisy singing and mating activities.
It is understood that the cicadas troubling the United States are periodical cicadas, including both the seventeen-year cicadas and the thirteen-year cicadas.
For the majority of their lives, they remain underground, surviving by feeding on the sap of tree roots.
After 13 or 17 years, they emerge from the ground, completing steps like molting, mating, laying eggs, and dying within a few weeks.
Because both 13 and 17 are prime numbers, these two types of cicadas only emerge simultaneously every 221 years. The last time this occurred was in 1803.
Experts predict that this year, in some areas, there will be at least one million cicadas per acre of land.
The mass emergence of cicadas can bring about unbearable noise for humans, as their chirping is among the loudest in the insect world, exceeding 110 decibels, which can be distressing.
In addition to the deafening noise, the sheer number of cicadas can also cause significant damage by feeding on tree sap and laying eggs, resulting in devastating harm to trees, with losses totaling millions of dollars.
Moreover, certain bird species that primarily feed on leaf-eating caterpillars may shift their diet to cicadas during such cicada outbreaks, leading to an increase in caterpillar numbers and further foliage consumption, resulting in plant losses.
