There was an unexpected* emergence of periodical cicadas in Jim Thorpe, Pennsylvania this spring. Experts believe it is a disjunct brood related to Brood XIV. Brood XIV is found in the area, according to entomologist and Pennsylvania-based periodical cicada mapper Marten Edwards, but perhaps not in the exact same specific locations. Brood II is also in the area, but on the other side of the mountain.
The terrain of the Jim Thorpe area is comprised of mountains & valleys belonging to the Appalachian Mountain system of the Eastern United States. I observed cicadas on mountain sides and in lower valley areas. They seemed most plentiful and gregarious on the edges of the forest, preferring small, young maple trees where they gathered, sang, paired off, mated and died. Although their numbers were lesser deep in the woods, I did find exit holes and exuvia there. The most interesting discovery was finding a fully sclerotized, but dead, adult cicada within an overturned tea cup left in the shade of an old tree. I discovered a few “cicada chimneys”, vertical structures made of soil surrounding exit holes, under pine trees where the cicadas seemed to need to extra hight to get above the thick layer of pine needles that littered the forest floor.
The best populations seemed to be along the Lehigh Gorge Trail from its entrance on Main Street to the Lehigh Gorge, and north, up the mountain the Lehigh Gorge Trail circumscribes, all the way to to Lehigh Gorge Drive. The trees along Route 903, starting at Old Pipeline Road and heading south, were loaded with active cicadas — so many, that it was hard to avoid their flying bodies as I drove towards downtown Jim Thorpe.
Here is a map of where I saw them. If you want to see them, go this weekend (June 24-26). They were plentiful in the Lehigh Gorge area:
The population seems to be entirely made up of Magicicada septendecim. No Magicicada cassini or septendecula were found (so far).
The annual cicada species are out now (now means May to September) around the United States. Not all annual cicadas are out yet — some won’t arrive until late summer — but many are currently out in the southernmost states, and will soon arrive in northern states.
We’re getting reports that their numbers are beginning to decline. Expect for them to be gone by the first week of July.
An unexpected population of periodical cicadas was found in Jim Thorpe, PA. They are thought to be derived from Brood XIV. Sometime within the last 10,000 years Brood V itself descended from Brood XIV.
Les Daniels found a small relic population of cicadas in Sandusky County, which isn’t supposed to have them.
Elias Bonoros found a population in Wildwood Park in Suffolk County, Long Island.
Just got back from West Virginia, Ohio and Maryland. Morgantown West Virginia, Hocking Hills & Vinton Furnace in Ohio, and Friendsville Maryland offered some great cicada observations for me.
The Noise! The Magicicada cassini species can be particularly loud, and we’ve seen reports in the 88db range. Don’t spend too much time around them when they’re that loud — like using a leaf blower or lawn mover, you could damage your hearing. Wait until July to have your big family barbecue. Here is a reference to noise levels. The frequencies of their call are particularly annoying for some people. And never put a cicada in your ear — they will get over 110db (see this video).
How much longer will they last? As of today (June 15th) their numbers should start dwindling and by the first week of July, they should be silent. Cherish them while they’re still around.
The Stink! Yes, if you don’t sweep them up, they will stink up your yard. They are fatty dead animals, after all. And like a strip of bacon left under your car seat, they will rot and produce a putrid bacony, cheesy odor.
The emergence is going strong, everywhere but Long Island. Report your sightings to Magicicada.org and it will be added to their map:
When: Generally speaking, these cicadas will begin to emerge when the soil 8″ beneath the ground reaches 64 degrees Fahrenheit. A nice, warm rain will often trigger a emergence. So, definitely May, but something might happen in April if we have a particularly hot spring.
Although the cicadas will emerge in MD, NY, OH, PA, VA and WV, the area is limited and patchy. No Brood V cicadas for D.C., Cincinnati, or NYC (people have asked). Their range is closer to this map (with cicadas in the orange areas):
Specific locations in L.I.:
Wildwood State Park – Confirmed!
Counties:Suffolk (Long Island).
Specific locations in Ohio:
The emergence should be good in the south eastern part of the state and in Summit, Medina, and southern Cuyahoga counties1.
Hocking State Forest, Hocking county, which is where James Edward Heath performed his investigation of periodical cicada Thermal Synchronization2.
Tar Hollow State Forest, in Laurelville, Hocking County, Ohio.
Strouds Run State Park, in Canaan Township, Athens County.
Read the paper: The 1999 Emergence of the Periodical Cicadas in Ohio (Homopetera: Cicadidae: Magicicada spp. Brood V) by Gene Kritsky, Jessee Smith, and Nicola T. Gallagher, published in 1999 in the journal Ohio Biological Survey.
Is it possible to raise cicadas? It is, but it requires patience and commitment.
The master of raising cicadas is a Japanese amateur cicada biologist named Shougo Murayama. Shougo has raised more than 1,000 cicadas of six or more species from eggs to adults in his backyard by growing them in see-through pots in clay soil with Aloe or Yucca plants. You can visit his website for more information (tip: use Firefox for better display of the text & then cut and paste it into Google translate). According to Shougo Murayama’s website, the cicadas he raised had 2 to 5 year life cycles.
David Logan of New Zealand successfully raised Kikihia ocharina cicadas from egg to adult. The details of this study can be found in the article Nymphal development and lifecycle length of Kikihia ocharina from 2006. It is important to note that K. ocharina have a short 3 year lifespan, and Logan raised the nymphs in pots with live plants. Logan’s study includes a section about care of the cicada’s egg before they hatch; hatching can take months, so this part is important. Logan placed the twig with eggs in a vial which he blocked with a moist material.
Logan conducted another study in 2014, this time with Amphipsalta zelandica (Boisduval), proving his methods work.
Richard Karban raised 15-year-old Magicicada nymphs to adulthood using peach trees as hosts for his study of how periodical cicadas keep track of time. This is not quite the same thing as raising cicadas from eggs, but it shows they can be raised outside of their natural habitat. Karban observed a high rate of mortality from the difficult process of transferring cicadas to new roots.
Most people who visit this website (Cicada Mania) are looking for American periodical cicada (Magicicada) information. Raising Magicicada would be quite a commitment. You’ll need an environment that mimics the Magicicada’s natural habitat, including the right soil & host plans, and you’ll need to maintain for at least 13 years (for the 13 year species, 17 years for the 17).
If you’re serious and live in the United States, a cicada with a short lifecycle like Diceroprocta apache will require less of a commitment.
Should you decide to raise cicadas, be sure to read the resources mentioned in this article, and consider the following tips:
Expect 95% of the cicadas to die
Care of the eggs is critical
Use host plants and soil preferred by the species
Use a species that has a short life cycle
Use see-through pots so you can see the cicadas as they develop
I might consider doing this experiment myself, but I would definitely choose a species with a short life-span. I might place some grasses in the pot, in addition to a larger host plant, to give 1st instar nymphs more tiny roots to choose from. I have a (perhaps irrational) fear of a house guest dumping a cup off coffee into my cicada host plant and killing the entire experiment.
Thanks to Chris Simon of The Simon Lab at UConn for pointing me to many of these references.
Logan, DP. 2006. Nymphal development and lifecycle length of Kikihia ocharina (Walker)(Homopetera:Cicadidae). The Weta, 31:12-22.
Logan, DP, Rowe CA, Maher BJ. 2014. Life history of chorus cicada, an endemic pest of Kiwifruit (Homopetera:Cicadidae). New Zealand Entomologist. 37:2:96-102.
Karban, R, Black CA, Weinbaum SA. 2000. How 17-year cicadas keep track of time. Ecology Letters. 3: 253-256.
The point of this article is that you should be on the alert for Magicicada periodical cicadas, no matter what year it is, and if you see or hear them, report them.
Stragglers, in terms of cicadas, are periodical cicadas that emerge in years prior to (precursors) or after their brood is expected to emerge. Most often, 17 year cicada stragglers emerge four years prior to their expected emergence date — but it is possible for periodical cicadas to emerge between 8 years earlier and 4 years later than expected. Read more about cicada stragglers.
This year (2016) Brood IX stragglers should emerge in southern West Virginia, western Virginia and the north-middle part of North Carolina that connects with western Virginia. See a map here.
Looking at the live map on Magicicada.org, it is obvious that most reports come from Brood V and stragglers appear to be emerging in the Brood IX & VI areas as expected — however, there are a fair number of reports in the Brood II and X areas, which is odd.
Red: Brood V
Orange: Brood IX, 4 years early (most probable)
Yellow: Brood VI, 1 year early (probable)
Green: Brood II, 3 years late (rare, but possible)
Dark Green: Brood X, 5 years early (rare, but possible)
As stated before, it is common for periodical cicadas to emerge 4 years early, but 5 years early is rare. So why Brood X be stragglers this year? That requires a little more thought.
Now we enter the realm of conjecture…
Rick Karban in the paper How 17-year cicadas keep track of time1 demonstrated how you can get cicadas to emerge earlier than expected if you alter the seasonal cycles of their host trees. Make the tree experience two cycles in one year, the cicadas will read this as “two years have passed” and they’ll emerge a year earlier. So, in the case of Brood X stragglers, it could be that their host trees experienced weather fluctuations that caused them to do something that signaled the cicadas that 2 years had passed. Add the 4 years they would likely straggle + 1 year caused by fluctuations from the host tree, and that makes for a 5 year straggler.
Growing Degree Days tell us why the Northeast had such an early surge in plant growth but then slowed. From late February to early April temperatures were near record warm in the Northeast with the 2nd most Growing Degree Days (GDD) in 25 years (chart/map left). This allowed plants to emerge way too early and then the freezes came!
Perhaps this early surge in plant growth, then a freeze, then growth again seemed like two years had passed to some cicadas. Perhaps.
1How 17-year cicadas keep track of time, Richard Karban, Carrie A. Black1 and Steven A. Weinbaum, Ecology Letters (2000) 3 : 253-256.
The media (news papers, bloggers, etc.) sometimes use terms to describe cicadas, and periodical cicada emergences, that range from simply incorrect to grossly hyperbolic. It is unclear if they do this to match reader expectations, to get more clicks, to write a more entertaining article, or simply because they don’t have all the facts. It bothers me when the media uses a photo or video of the wrong species, which is why I have the use the correct image page.
What media mistakes have you witnessed? Let us know in the comments.
Professor Chris Simon, of the University of Connecticut Simon Lab, is one of the premier cicada experts in the world. She provided us with her list of Magicicada Media Faux Pas (below). How many of these have you seen? Can you think of more?
Incorrect Descriptive Words
“swarm” They don’t swarm—i.e. fly around in large groups.
“invasion” They don’t invade. They have been there the whole time.
They are not a plague like grasshoppers that come in and eat everything–they don’t chew leaves. They suck.
“overrun” Implies that they are imposing us when in fact we are much more of an imposition on them–clearing their trees and building Walmarts on top of them.
Here are some more funny ones…
“lurking underground” They are not lurking or threatening, they are innocently feeding on tree roots.
“hatching out of the ground” They don’t hatch out of the ground, they hatched from eggs in tree branches 17years ago.
Soil temperature triggers periodical cicada emergences:
James Edward Heath in his paper Thermal Synchronization of Emergence in Periodical “17-year” Cicadas (Homoptera, Cicadidae, Magicicada)1 discovered that periodical cicadas will emerge, on average, when the soil 8 inches below the ground reaches 64 degrees Fahrenheit:
Soil temperature at 20-cm [7.87 in] depth in seven locations averaged 17.89 C [64.202 F] at the time of emergence, regardless of date. Cicadas emerging from burrows had average body temperatures of 18.04 C [64.472 F]. Synchrony in emergence may be due to animals reaching a critical threshold temperature.
The soil warms their bodies and that triggers the cicadas to emerge.
A warm rain, which will seep into the earth and warm the bodies of cicadas, can trigger a “particularly intensive” emergence.
Alexander and Moore (1962) noted that emergences were par- ticularly intensive following warm rains ( > 2 0 C ? ). I believe this suggests that the soil temperature probably was near emergence tem- perature and the heat transported by the water percolating into the ground warmed the soil sufficiently to raise soil temperature above the emergence threshold.
Some unanswered questions I have are: 1) how long does the temperature have to be 64°F+ – just a moment, or a certain number of hours, and 2) because we know not all cicadas emerge instantaneously, what is the maximum temperature that for certain will clear them from the soil?
This is an example of a temperature probe use to study the emergence temperature of cicadas. The probe in this picture is held by cicada researcher Gene Kritsky:
Note that males typically emerge before females, and that the larger ‘decim species emerge before the smaller cassini species.
I think I know what you’re thinking: “I don’t own a temperature probe, how can I guess when the temperature is 64°F 8” below the soil? Direct sunlight, air temperature and rain warms the soil. Southern facing land will warm sooner than northern facing land. Land in direct sunlight will warm faster than land in shade. Rainfall on a 80°+ day will quickly do the trick, but two weeks of temps in the 70°’s should work as well. So keep an eye on the 10-day weather forecast and watch for those days in the 70s, and especially the 80s.
Minimum Flight Temperature:
Their body temperature needs to be a little warmer than that to fly. Their minimum flight temperature (MFT) is 18-21°C / 65-70°F. The temperature varies depending on the Brood and species. They’ll need a few more degrees before they’re fully functional, and start singing and mating.
So, until their bodies are about 72°F (“room temperature”) they won’t be flying, singing and mating.
Maximum voluntary tolerance temperature:
Maximum voluntary tolerance temperature (MVT) for periodical cicadas is 31-34°C / 88-93°F, again depending on Brood and species. Maximum voluntary tolerance is the point at which cicadas seek shade and when thermoregulation takes precedence over other behaviors.
If you’re writing an article about the coming emergence of the 17-year periodical cicadas, please use the correct genus & species of cicadas.
The genus of all 17 year cicadas is Magicicada, and they are never green. The three species of 17-year cicadas are M. septendecim, M. cassini, and M. septendecula. They’re all black with orange wings and legs and red eyes (some exceptions, but they’re never green).
An adult Magicicada septendecim by Dan Mozgai/cicadamania.com:
A newly emerged, teneral, Magicicada septendecim by Dan Mozgai/cicadamania.com:
A mating pair of Magicicada septendecim by Dan Mozgai/cicadamania.com:
Today I came across a paper about Brood VII called The Periodical Cicada Brood vii Revisited (Homoptera, Cicadidae) by L. L. Pechuman, published in 1985 in the journal Entomology News (link to the article). Brood VII will be back in New York in 2018 (not too far away) so I’m glad I found this now. Brood VII is interesting because it is geographically isolated from other broods, near the Finger Lakes area of New York. This always makes me wonder what happened that led to their isolation (glacial melting, a massive die off of host trees… who knows).
The article is a quick, but melancholy read — unfortunately Brood VII is a small and dwindling brood; it has gone extinct in many areas, and has suffered over-predation by birds in recent emergences. “Populations were just not high enough to support ‘predator satiation'”, according to L. L. Pechuman.
People who witness massive periodical cicada emergences would never think that they were a fragile insect, but they are and papers like this make that fact abundantly clear.
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