Each summer, Illinois residents can hear the sounds of annual cicadas in the trees day and night, but this year the state saw a rare emergence. Two groups of periodical cicadas, Brood XIII and Brood XIX, have appeared simultaneously for the first time in over 200 years, making Illinois one of only two states to see both broods this year.

Although cicadas can be seen each year, the emergence of the two periodical broods creates a once-in-a-lifetime experience as it is estimated that it will be another 200 years before more than one brood emerges at the same time.

Within Illinois, it is reported that Chicago and Northern Illinois have the highest counts of Brood XIII and Southern Illinois has the highest count of Brood XIX. Both broods can be seen across Macon, Sangamon, Livingston and Logan counties.

Cicadas spend a majority of their lifespan underground, roughly 13-17 years, before they emerge and die within just a few short days. During their time above ground, their buzzing sounds can be heard and their molts can be seen upon the trees.

Brood XIII is described to be a blue-eyed cicada, rather than the normal red eye that is seen more commonly in annual cicadas, and is a brood that emerges every 17 years. Brood XIX is a combination of four different species, and made its first above ground appearance in 2011, while only being discovered in 1998, and emerges every 13 years.

To learn more about Brood XIX, visit: https://dnr.illinois.gov/education/wildaboutpages/wildaboutinvertebrates/wildabouttruebugs/wai13yearcicada.html

To learn more about Brood XIII, visit: https://dnr.illinois.gov/education/wildaboutpages/wildaboutinvertebrates/wildabouttruebugs/wai17yearcicada.html