Preliminary Mid-Atlantic periodical brood map
This map has been produced based on the results of an extensive search of Mid-Atlantic museum specimens and literature records as well as field research conducted to document the occurrences while the broods are emerging. I have found that the Periodical Cicada broods in the Mid-Atlantic states tend to fit together like puzzle pieces and while 2 broods may occur in the same county, I have not found them to overlap. Upon closer examination, many older records of overlap can be explained by 4-year or 1-year accelerations or decelerations of the existing brood in that area.
have received many inquiries from
area that most people are interested in is Southern Maryland and the
Eastern Shore. Saint Mary’s, Calvert and Charles counties had Brood II
emerge in 1996. Some areas of northern St. Mary’s, northern Calvert and most
of Charles county did not see the emergence of Brood
II. But, based on all the historical, literature and museum specimens for the
past 100 years, Brood X should not occur below a line from
Once the periodical cicadas emerge this month, negative records are also very important. Please report any areas in Maryland where you do not have periodical cicadas emerging. This will help document what is actually occurring out there. Thank you.