Why another cicada website?
This website has been created to act as a repository for information regarding annual and periodical cicadas found in the Mid-Atlantic area of the United States. This area includes Delaware, Maryland, New Jersey, North Carolina, Pennsylvania, Virginia, and West Virginia. Information such as life history information, distributional information for each species, color photos of males and females of each species, call files for each species, as well as calling phenology and temperature ranges during calling have been collected for species occurring in this geographic area. The purpose is to provide interested people, students and teachers the needed resources to understand the distribution and life histories of our local cicadas.
What is the difference between a periodical cicada and annual cicada?
Cicadas in our area can easily be divided into two groups according to when they occur; those that appear every year (or annually) from the end of June to the middle of October and those that do not appear every year, but occur every13 or 17 years (or periodically) generally from the middle of May to the middle of June. There is also a difference in their appearance. Annual cicadas vary in size from a ¼ of an inch to almost three inches in size. They tend to be black, brown and green and have a green coloration along their wing margins. The periodical cicadas are generally all black with red eyes and orange wing margins and are generally an inch in length. Periodical and annual cicadas would rarely occur at the same time. Some annual species can begin calling as early as mid-June here in the Mid-Atlantic, however most species tend to call as individuals and not the famous huge chorus that the periodicals are known for. The annual cicadas would only begin to call after all the periodical cicadas have died off.
What’s a Brood?
A brood is a group or age class of periodical cicadas that emerge in the same area during the same year. For the sake of tracking the emergences, Charles Marlatt in 1907 designated roman numerals for each of the potential year classes that could occur. He designated I (1) -XVII (17) for the seventeen year periodical cicadas and XVIII (18) to XXX (30) for the thirteen year periodical cicadas. However, there may not be a periodical cicada Brood emerging every year. Over the last 100 years, researchers have documented the occurrence of 12 Broods of 17 year cicadas (I,II,III,IV,V,VI,VII,VIII,IX,X,XIII & XIV) and the possible demise of Brood XI in Connecticut. (There is no Brood XII, XIII, XV, XVI or XVII.) There are only 3 existing Broods of 13 year cicadas; XIX, XXII, XXIII, the other ten don’t exist.
Here in the Mid-Atlantic States, the picture has been somewhat clouded for a number of reasons. One important reason is that periodical cicadas are not always punctual. Some populations for various reasons emerge 4 years or 1 year ahead of schedule. This can lead a great deal of confusion. There has also been some mis-identification of periodical cicadas for early emerging annual cicadas. Many authors over the past hundred years have also extrapolated the occurrences back for many cycles of 17 years, based only on one record. These records have been erroneously perpetuated through subsequent publications on a broods historical range. In the southern portion of the Mid-Atlantic, many emergences of Brood XIX of the 13 year cicadas were mistaken for 17 Year cicadas that were emerging elsewhere in the Mid-Atlantic. This is one reason why different broods have been reported from the tidewater area once and never reported again.
To locate information easier, this website has been divided into two basic sections; periodical cicadas and annual cicadas. These sections are further subdivided into individual species life histories, calling sound files and timelines, temperature regimes, photos of males and females, and distribution maps. Photos and sound files are currently not available for all species, but research is ongoing to provide these.
A number of individuals have been instrumental in making it possible for me to accomplish my research goals. Through their contributions of time, knowledge and encouragement, I have increased my understanding of periodical and annual cicada species. I would like to recognize them for their contributions.
Gaye Williams, Entomologist, Maryland Department of Agriculture, Annapolis, MD
Who for many years has always been available for questions and a great resource for information on periodical cicadas.
Dr. Thomas Moore, Professor Emeritus, University of Michigan, Ann Arbor, MI
Who has graciously supplied me with his outstanding collection of periodical cicada locality records that he has accumulated over the past 50 years.
Dr. David Marshall, Post Doc Graduate at the University of Connecticut, Storrs, CT
Who has tolerated countless hours of and e-mails with questions regarding periodical cicada broods and their distribution. He and John have always been available and encouraging in anything I was interested in knowing or studying regarding cicadas. Their willingness to share their research finding and methods has always surprised me.
Dr. John Cooley, Post Doc Graduate at the University of Connecticut, Storrs, CT
Who has also tolerated countless hours of and e-mails with questions regarding periodical cicada broods and their distribution. He and Dave have always been available and encouraging in anything I was interested in knowing or studying regarding cicadas. Their willingness to share their research finding and methods has always surprised me.
Dr. Alan Sanborn, Cicada Taxonomist, Barry University, Miami, FL
Who in my opinion is the leading expert on annual cicada species in North America and has tolerated my less than desirable museum specimen identification skills.