There is a new paper out about Brood XXII, titled Evolution and Geographic Extent of a Surprising Northern Disjunct Population of 13-Year Cicada Brood XXII (Hemiptera: Cicadidae, Magicicada). I helped with the field work for this paper, traveling through Ohio and Kentucky with Roy Troutman, recording the locations of periodical cicadas.
Brood XXII, a brood of Magicicada periodical cicadas with a 13-year lifecycle, exists in Louisiana & Mississippi, and Ohio & Kentucky with no geographic connection between them (the two groups are geographically isolated). The paper discusses the similarities and differences between the two groups.
Citation for the paper:
Gene Kritsky, Roy Troutman, Dan Mozgai, Chris Simon, Stephen M Chiswell, Satoshi Kakishima, Teiji Sota, Jin Yoshimura, John R Cooley; Evolution and Geographic Extent of a Surprising Northern Disjunct Population of 13-Year Cicada Brood XXII (Hemiptera: Cicadidae, Magicicada), American Entomologist, Volume 63, Issue 4, 12 December 2017, Pages E15–E20, https://doi.org/10.1093/ae/tmx066
Update: After emailing with Dave Marshall and John Cooley today (July, 17th), I learned that the ‘decim cicadas in this brood are Magicicada tredecim (not neotredecim), based on their lower-pitched sound and very-orange abdomens! This means that this brood is not related to Brood XIV or X at all, that these cicadas are truly 13-year cicadas, they might be related to Brood XXII and perhaps were once part of the same larger brood thousands of years ago.
Back in 2013 Roy Troutman and his wife Michelle visited me in New Jersey to experience the Brood II cicada emergence. At that time, Roy extended an invitation to visit Ohio in 2014 to experience & map a mysterious brood that emerges every thirteen years near his family campsite. A year later, I took him up on his offer.
A very orange M. tredecim found by Roy in Ohio.
On June 1st I made the long drive from the Jersey Shore to south-west Ohio. The trip went smoothly, thanks to a well maintained car, a flash drive filled with 37 Gig of music, Red Bull, Monster Energy Drinks, some M&M candies and a tank and a half of gas. Sunday night I met Roy at his family home. After a quick dinner, we immediately went looking for cicadas in Point Pleasant, Ohio. Most of the cicadas had emerged from the ground a week or two ago, but we were able to find a few newly emerged specimens:
The following morning we visited the Crooked Run-Robert J. Paul Memorial Sanctuary in Chilo, Ohio, which is primarily a hardwood forrest along the Ohio River. The nature sanctuary was loaded with Magicicada tredecassini, healthy pockets of M. tredecula and a few M. tredecim. The cicadas were chorusing, feisty and already ovipositing (laying eggs).
So, why spend a week researching cicadas? Why ride in a car for dozens of hours tracking the locations of cicadas? Well, this mysterious Ohio & Kentucky brood is unique, and this would be the first time it was thoroughly mapped.
Why is this Ohio Kentucky brood unique?
These cicadas have a 13-year life cycle. No other brood of periodical cicadas in Ohio has a 13-year life cycle. Note that two 13-year broods (XIX & XXIII) exist in Kentucky, but they are geographically isolated from the OH/KY brood.
The OH/KY brood is also geographically isolated from Brood XXII, a brood of 13-year cicadas that emerged in Louisiana and Mississippi this year (2014). The OH/KY brood might be grouped with Brood XXII just by virtue of the fact that they emerge in the same cycle of years, but the two broods seem to be too far apart, geographically and probably genetically, to be related.
They occupy a relatively small area of south-western Ohio, and north-central Kentucky.
They are in relatively the same area as two 17-year broods, Brood XIV and Brood X. Brood XIV more so than Brood X.
The mystery is: why does this small, isolated brood of 13-year cicadas exist?
Roy Troutman and John Cooley have collected specimens, and the insects genetics will be studied to try to find an answer. Along with the results of genetic testing, the results of mapping will be considered, along with the past work of researchers like Lloyd and White, and local legend Gene Kritsky.
Mapping cicadas requires that you drive hundreds to thousands of miles, listening for cicadas, and recording the species and location. The hard parts are 1) picking out the individual species (particularly hearing individual deculas in the midst of loud chorus of cassini), and 2) driving slow enough to hear the individual species, without enraging local drivers. Discerning the songs of individual species is easy enough when you’re moving slowly or standing still, but at 55mph, you can hear the roar of a cassini chorus, but a more subtle ‘decim chorus, set deeper in the woods, will go unheard.
Thanks to John Cooley’s Map O Matic — a combination of a tiny laptop, Ubuntu Linux, a numeric keypad, a GPS puck, and some clever programming — marking the locations of Magicicada species is now a simple task. Drive around, and when you hear a heavy ‘decim chorus, you hit the 9 key, and the location is recorded. Hear a ‘cassini individual; hit a 4, and the location is recorded. Genius. I suppose the next best thing would be an app version.
The Cicada Map O Matic
Each day Roy planned the route and we started mapping. Roy driving; me pressing buttons. We traveled highways, and single-laned roads; through heavily populated suburbia with convenience stores selling Pork cracklings and fireworks, as well as, farm and forrest roads. Straight and fast. Winding and bumpy. Each day was amazing road trip for the sake of cicada research.
Mapping can be frustrating. Time limitations are frustrating. The cicadas only sing for a few weeks, so there is only so much time to hear and map them.
Google Maps, often used to visualize cicada mapping data, is frustrating as well. Google maps omits unincorporated towns and villages from their maps. Want to find Utopia, Ohio on Google Maps? According to Google Maps, it doesn’t exist.
Also, if you use an old map, beware; a road that existed 10 years ago, might now be a rocky field. One time we headed down a dusty road that looked like it connected to a major county road. Instead, Roy ended up breaking some part of his car on some bowling ball sized rocks, which I had to get out and move so we could backtrack to civilization. One positive: while rolling boulders, I heard an individual Magicicada tredecim, which are rare in this brood. Hit the 7 on the cicada Map O Matic.
The data from all this cicada mapping will be used by cicada researchers like Gene Kritsky and John Cooley to decode the mystery of this brood. If you’re curious, you can see the map here, or take a look at this short video, which crudely demonstrates the geographic proximity of Brood XIV, the OH/KY Brood and Brood X:
My trip to Ohio and Kentucky, was fantastic. I got to spend dozens of hours helping to map an important brood, hang out with a good friend, and even meet cicada research legend Gene Kritsky for breakfast. For a cicada fanatic, it doesn’t get much better.
A Magicicada tredecassini found in Kincaid Park, Kentucky.
I had such a good time, I headed home via Kentucky (which is not the way to go, if you’re going back to New Jersey). I stopped by Kincaid Park so I could hear all three species in one location. I even drove down the shoe road, and visited the Jim Beam distillery (which has little to do with cicadas, but why not).
After spending a week mapping cicadas, my respect for cicada researchers like Gene, John, Roy, Chris Simon, David Marshall and Jin Yoshimura has grown measurably. Mapping is not easy. It takes concentration, patience, a lot of expensive gasoline, and energy drinks. It’s worth it though. Hopefully I’ll get to do it again next year as well.
Magicicadas with a 13-Year life-cycle are emerging in Ohio & Kentucky, along the Ohio river, in 2014. This particular group of periodical cicadas last emerged in 2001 and 1988.
July 17th: I got confirmation from Dave Marshall and John Cooley that the ‘decim in the brood are Magicicada tredecim!
June 5th: Roy Troutman and I completed 3 days of cicada mapping in Ohio and Kentucky. This map includes our findings, Gene Kritsky’s findings and sightings submitted to Gene from local residents.
June 4th: Audio of a Magicicada tredecula call from the Ohio/Kentucky brood.
June 3rd: I spent the last last two days looking for cicadas in Ohio and Kentucky with Roy Troutman. Mostly ‘cassini, some ‘decula, and a very small amount of ‘decims. We found ‘cassini chorusing in Mason, KY, in the west, and so far as south as Neurls Run, KY. JoAnn White & Monte Lloyd’s paper 17-Year cicadas emerging after 18 years: A new brood?1 mentioned emergences in the Mason location, going back to 1975 (three 13 year generations ago).
May 31th: Cicadas are reported to be “loud and plentiful” in the Germantown KY area, as well as, Harrison county KY.
May 30th: Roy Troutman confirmed that ‘decula, ‘cassini and ‘decim type Magicicada have emerged in Ohio.
May 23th: Gene Kritsky wrote to let us know that “the emergence is now in full swing” in Ohio and Kentucky. Roy also shared a photo of an adult 13 year cicada.
May 14th: Roy Troutman has reported that the emergence began last night in Chilo, OH according to a Clermont County Parks director. Cool weather this week (in the thirties!) will likely prevent more cicadas from emerging until next week (highs in 80s).
I know what you’re thinking: are these cicadas part of Brood XXII? Time and research will tell. Brood XXII emerges in Louisiana and Mississippi, which are geographically isolated from Ohio & Kentucky, so the two groups of cicadas are likely to be genetically distinct (belonging to different mitochondrial haplotype groups at least). That said, Brood II, which emerges mostly along the east coast of the U.S., also emerges in Oklahoma, which is geographically isolated from the rest of that brood. So, the Ohio/Kentucky cicadas could logically be part of brood XXII.
Back in 2001 Roy Troutman, Les Daniels and Gene Kritsky reported this group of cicadas to Cicada Mania. Les reported both cassini and decim.
My guess is these cicadas are somehow descended from Brood X or Brood XIV 17-year cicadas, and that if they are 13-year cicadas.
I wrote Roy for a list of towns where these cicadas emerged in 2001, and he said:
Cold Springs, KY
New Richmond, OH
Point Pleasant, OH
Woodland Mound Park, Cinncinati, OH
Roy Troutman, Gene Kritsky and his wife Jess witnessed a Magicicada emergence in Finneytown Ohio tonight. It is believed that this could be an acceleration of a new Brood VI, or an eight year acceleration of Brood X.
We had an unexpected emergence in parts of the Cincinnati area last night & I got some pics with my new Canon t4i. Gene [Kritsky] & his wife Jess came out to witness it as well. I would say hundreds emerged in a very small suburb of Cincinnati called Finneytown. This could be 4 year acceleration of the new brood VI that Gene has been talking about verifying in 2017 or 8 year acceleration of Brood X.
Gene Kritsky is one of the leading periodical cicada researchers. He’s asked that we help with his research regarding temperature and cicada emergence. He needs to know the date that cicadas first emerge, and then the date when they appear in large numbers in a given locality. To contact Gene with your findings, email him at email@example.com.
Here are the details:
I wanted to alert you to a paper that I published with Roy after Brood XIV. I had placed sensors at cicada depths in Roy’s backyard, and also hung others in the area trees. We recorded the temperatures at 10 minute intervals at all the locations. I was trying to find a weather model to predict soil temperatures without using probes. This would be cheaper for people wanting to monitor an impending emergence. This research is based on what potato farmers do to track the growth of their crop.
We found that the average of the running three day and two day mean temperatures was a good predictor of soil temps.
The formula along with the extended forecast can be used to forecast soil temperatures. Once we get the 64º F soil temps and a nice rain we got emergences. I am hoping to test this model again this year, which in part is why I emailing you. What I need to know is the date that cicadas first emerge, and then the date when they appear in large numbers in a given locality. I will then use weather data to check the soil model. Can you ask readers to send me that info? Many thanks.