For the first time in 221 years, two distinct cicada broods will emerge at the same time, bringing a few billion red-eyed insects into our springtime air.
Cicada Brood 19 and Brood 13 will overlap this year, marking the first time they have come out at the same time since 1803. Alabama has over 20 species of annual cicadas, which appear every summer, but this summer’s broods are special: The insects are underground for 19 and 13 years, respectively, and emerge in the millions, all at once.
“It’s the first time they have overlapped in 221 years, which makes it a pretty rare event,” said John C. Abbott, chief curator and director of museum research and collections at the University of Alabama.
These cicadas will most likely emerge from the ground at the end of April or early May. They create rackets, mate, lay eggs in twigs and die within three to four weeks.
Brood 13 cicadas are expected in northern Illinois, Iowa, and northeastern Indiana, while Brood 19 cicadas are expected in southern Illinois, Missouri, Arkansas, Tennessee, Louisiana, Mississippi, Alabama, Georgia and South Carolina.
Why the difference between annual, 13- and 19-year broods? Abbott said the insects have evolved so that their emergences don’t coincide with the activity of their predators. Long periods of time underground help them outlive the competition, too.
With billions of small insects coming out of the ground; some people might be a little scared. There’s no harm to the average person, though: Cicadas feed on trees.
Even “zombie” cicadas, which are ridden with a parasite, massospora, don’t pose a threat to humans. The sexually-transmitted parasite just circulates within cicadas.
“What is really cool is it turns them into what sometimes people refer to zombie cicadas where it actually affects their brain, and they become more sexually active,” Abbott said. “So it’s just one more interesting way that nature has evolved for species to fight these battles.”
