Brood I Periodical Cicadas in the Virginias
News Category: Cicada General Info
Brood I Periodical Cicadas in the Virginias
As the 2012 spring and summer cicada season commences, we can expect the arrival of yet another periodical cicada event. As mentioned in 2011, there will be periodic cicada emergences somewhere in the eastern United States starting in 2011 and continuing each year until 2021.
The 2011 cicada season gave rise to perhaps one of the largest periodical cicada emergences in North America. The arrival of Brood XIX periodical cicadas included 16 southern and eastern states and contained 4 different species.
If you would like to read more about the Brood XIX event check out the links in the right-hand column under the heading "Brood XIX Information".
The spring and summer of 2012 is the scheduled emergence of the periodical cicadas from a different year-class known as Brood I. They are a 17 year variety of periodic cicada containing three distinct species.
Brood I periodical cicadas will not have as wide a distribution as Brood XIX. Brood I is a smaller brood with the majority of species expected to appear in the Appalachian Highlands. Specifically, along the Valley & Ridge and Blue Ridge Mountain physiographic provinces of western Virginia and eastern West Virginia.
What does this have to do with Massachusetts Cicadas?
Good question. One of the mandates of Massachusetts Cicadas is to document the different species of cicadas not only Massachusetts and New England but in other parts of the United States as well. One of our first projects involved documenting Brood X periodical cicadas in 2004 in the mid-atlantic states.
Since then, Massachusetts Cicadas has been involved with the distribution mapping of all subsequent periodical cicada broods and collaborating with other researchers around the country and sharing information.
In 2008, Massachusetts Cicadas spent a lot of time on Cape Cod because in that year, Brood XIV periodical cicadas made an appearance. As with previous brood emergences, Massachusetts Cicadas has been involved in a rather large effort to map the distribution ranges of all periodical cicada broods.
The previous year, 2007 Massachusetts Cicadas went to the mid-west and participated in a big distribution mapping project through a grant from National Geographic and the University of Connecticut at Storrs. That Brood was known as Brood XIII.
What Are Periodical Cicadas Broods?
Periodical cicadas are those cicadas from the genus Magicicada and contain 7 species. They have the longest juvenile period (nymph stage) and because of this they are considered some of the longest-lived of all insects. Three species of Magicicadas emerge en-mass every 17 years and 4 species emerge en-mass every 13 years.
Periodical cicadas appear in different geographic regions of the United States and are broken down by year-classes known as Broods. Today there are 15 different broods of Magicicadas. Twelve broods being 17 year Periodical cicadas and three broods being 13 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) to XVII(17) for the seventeen year periodical cicadas and XVIII(18) to XXX(30) for the thirteen year periodical cicadas.
Periodical Cicadas are small and are mostly black with clear membranous wings, orange wing veins and bright red eyes. Some hybrid Magicicadas have been recorded as having silver, blue or gray eyes and are considered quite rare.
Periodical Cicadas are Developmentally Synchronized.
That's the reason for these mass emergences. Magicicadas of the same brood in any given region will emerge at roughly the same time every 13 or 17 years. In fact since Periodical cicadas are so developmentally synchronized that, if all the Magicicadas of any given Brood were to be wiped out in the year of their emergence before the females could deposit their eggs after mating, then that particular brood would become extinct. It is believed that this happened with Brood XI which was from the Connecticut River valley region of the United States and was last seen in 1954.
Periodical Cicadas are predator foolhardy - a species is considered predator foolhardy when they overwhelm the problem of being preyed upon by their sheer numbers. In a brood year there are so many emerging Magicicadas (around 150,000 to 1,500,000 per acre) that they overwhelm local predators that normally prey on insects. The need to run from predators isn't necessary. Even if 1/2 - 3/4 of Magicicada numbers are eaten, a theoretical point known as Predator Satiation kicks in. That is after the predators that prey on Periodical Cicadas have eaten their fill, the predators will no longer be interested in eating them but there will still be many Magicicadas left over to mate and continue the brood for the next emergence cycle.
Look for the Early Signs
If you are in an area that is expecting a periodical cicada emergence, beginning in mid-May and depending on outside temperatures, you may be able to find early signs that soon Periodical Cicadas will emerge in your area if you know where to look.
Exit holes and mud chimneys. Right now Brood I periodical cicadas are just below the surface. Periodical cicadas especially the species known as M. septendecim dig exit holes and may sometimes build mud chimneys like the one on the right. They do this in preparation for emerging. If the soil temperature isn't quite right they will construct mud chimneys to get themselves out of wet areas because the nymphs do not like the wet and like to stay dry. You can find these exit holes and mud chimneys under old logs, rocks or old plywood boards. You can even find them in the crawl-spaces under your porch or deck. We looked for and experienced this in 2007 for Brood XIII Periodical Cicadas in Chicago on May 15th.
Immature Nymphs. Sometimes you can even see the little immature nymphs wallowing around in their tunnels and mud chimneys like the one on the left. You can tell an immature nymph from a fully mature nymph because they (the immatures) are usually light beige in color and lack the dark almost black patches on their pronotum.
If you spot them in this state please take the time to fill in the "Report Brood I Periodical Cicadas" form.
What to Expect During the Emergence
Crazy Emerging Nymphs - As the emergence gets underway you can expect to find Brood I periodical cicadas emerging from the ground in record numbers during the first week or so. You will find nymphs clambering for position on virtually any vertical surface or underneath leaves that they can find in trees. They tend to be pretty aggressive towards each other as they struggle to find a secluded spot where they can molt in peace.
During the Molting Process
The Teneral Stage - The molting process will take around 1.5 to 2 hours to complete. A newly molted cicada is known as a "teneral". They are very soft and white with bright red eyes. Have you ever had a soft-shelled crab? Like crabs, cicadas are arthropods and like most arthropods all go through a molting process to shed their old shell or skin. The new version usually comes out all soft. This is the state the newly molted cicada is in.
Eventually though, the cicadas will "harden up" and their bodies will turn black. Their wing veins will turn orange and their wings will become transparent.
Now it's Time to do a Whole Lot o' Nothin'
After the molting process and after they have sufficiently hardened AND if there are plenty left over after the local predator populations have had their fill, the periodical cicadas will just kind of sit there doing nothing. They will aggregate together though. You will find a lot sitting in low bushes, while some will be making their way to the tree tops by either walking or flying but there won't be much singing going on. It has been speculated that at this time, it takes a while (like a week or so) for the cicadas to become sexually mature. Until that time, you will see a lot warming themselves in the sun amongst their cast-off nymph skins. Similar to the picture above and to the left. Click the thumbnail to enlarge.
Once the initial week is over, you may hear some light singing going on. A few single males will start to sing. Eventually, this will cause other males to sing. Then that is when the fun really starts!! Click the thumbnail to the right to listen to a lone male M. septendecim calling.
Once the Brood I Periodical Cicadas are in Full Swing
In addition to M. septendecim, you may also experience the other two species, M. septendecula and M. cassini. These sound quite different from M. septendecim. Click the thumbnail to the right to listen to a singing chorus of M. cassini. What do they sound like to you?
The Brood I Distribution Mapping Project
Periodical cicadas may answer questions concerning speciation, species boundaries, and post glacial biogeography. If we can draw accurate maps - and we can with current technology - we can answer a lot of these questions. Distribution maps prior to this era are loaded with inaccuracies and really didn't address the question of early and late emergences (straggling), boundary overlap and periodical cicadas just being blown around on the wind! The data that we compile through this web site will be shared with others' research data in order to assemble these accurate maps.
How do I Report periodical cicada emergences in my area?
Brood I periodical cicadas will have a rather small distribution. However, if you happen to be within the expected distribution range, you can still fill in the Report Brood I Periodical Cicadas form. We have also added the option of uploading photos should you wish to share your periodical cicada sighting reports on Massachusetts Cicadas
A Collaborative Effort
The data that is collected through this web site is just the tip of the iceberg. Massachusetts Cicadas is just one of many sites that not only collects data for personal research projects but the data is also shared with other sites and research groups like Magicicada.org, a site that was just created to map all 13 and 17 year periodical cicada broods.
Still Want More? Join Entomology-Cicadidae
If you're curious to learn more about Periodical Cicadas or Annual Cicadas, please take the time to join Entomology-Cicadidae. Founded by Massachusetts Cicadas in 2005, Entomology-Cicadidae brings together people from all over the U.S. and around the world who are interested in learning about these amazing insects. Everyone is invited to join, from individuals who are curious and want to know more about cicadas to main-stream researchers who are discovering new things just about every cicada season. Ask your questions or join the discussion and contribute what you know.
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Click the like button in the right-hand column above and stay up-to-date on everything that happens with Massachusetts Cicadas. The fun doesn't stop once Brood I goes away. We are also out and about researching and documenting other cicada species from around Massachusetts, New England and the United States.