What is Brood X?
Periodic crickets, as they are known, are different from annual crickets. They spend almost their entire life a few meters underground and live on sap from tree roots. Then, in the spring of their 13th or 17th year, depending on the type, adult cicada nymphs emerge for a short adult stage, synchronously and in huge numbers – really huge numbers – for a massive mating frenzy.
Groups of crickets that share the same emergence years are known as broods. This spring, it’s time for members of one of the largest broods of 17-year-old crickets, dubbed Brood X or the Great Eastern Brood, to crawl out of their subterranean hideouts and show off their black bodies and bold red eyes.
The insects will climb up the nearest vertical surface. They will shed their exoskeletons and inflate their wings. After resting for a few days and waiting for their shells to harden, mating will begin. The burst of activity is impossible to miss as hordes of males start broadcasting their high-pitched mating song. This is done through sound-producing structures called tymbals on either side of their abdomen.
“They can gather … in parks, forests, neighborhoods, and can seemingly be anywhere,” explained Michigan State University entomologist Gary Parsons in an MSU question and answer session on the phenomenon. “When they are so numerous, they fly, land and crawl everywhere, also occasionally landing on people.”
Where and when will Brood X come out?
Parts of 15 states, as well as Washington, DC, will hear the romantic serenades of males in trees trying to attract females. The states are Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, North Carolina, New Jersey, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia.
The return of the crickets usually starts around early to mid-May and lasts until the end of June. Sightings of adult crickets have been reported in some states, including Georgia, Kentucky, Maryland, North Carolina, Pennsylvania, Tennessee, and Virginia. The bugs have also surfaced in the Washington, DC area. Residents of those areas are busy sharing the evidence on social media, while other places are still waiting for the big arrival of the bugs.
How do crickets sound?
It varies by species, but it can sound like a high-pitched electric hum, a chirp, or a rattle (hear it below). The call of a group of men can be over 90 decibels, about the same level as a motorcycle about 8 meters away. The females respond to the males’ calls by clicking their wings, and all the back and forth movement creates a distinctive symphony.
Listen to the 17 year old crickets
Can crickets hurt people? How about trees?
No, the insects are harmless. They don’t sting, bite, or carry disease, and they don’t usually get in, although they do gather on outside walls.
“The only way they could get in is accidentally fly in through an open door or window, or because they landed on a person who then carried them in unnoticed,” said Parsons.
During dense emergence, females can lay enough eggs in branchesBut the abundant egg laying also prunes trees, of course, resulting in more flowers and fruit in the years that follow. Crickets also have other ecological benefits. Periodic crickets aerate large amounts of soil when they emerge en masse, and when they die, their decaying bodies enrich the soil with nutrients.
Can pest control agents help me?
When people ask for help during the crop of cicadas, those in pest control are largely in a position to educate customers on why the pest control workers don’t show up to spray their garden with pesticides.
“We really want people to understand and know that pesticides are not the answer, which sounds really funny if you come from a pest control company,” said Frank Meek of pest control company Orkin.. “Pesticides are not the thing to use for this insect. They don’t work for it, and it’s a waste of product, and it’s a hazard to the environment to spray on just because you’re afraid of the crickets.” ”
Why do so many crickets appear at once?
It is thought that by showing up in such large numbers, enough of them can evade predators and live on to mate – in fact, force in numbers.
The crickets usually start hatching when soil temperatures reach 64 degrees Fahrenheit (18 degrees Celsius) 20 inches below ground. “That seems to be the trigger that makes them all show up in one area within a few days or weeks,” says Parson. A warm rain often causes their emergence.
Because periodic crickets are sensitive to climate, patterns of different broods and types reflect climate change, note John Cooley and Chris Simon, professors of ecology and evolutionary biology at the University of Connecticut.
“For example, genetic and other data from our work indicates that the 13-year-old species Magicicada neotredecim, which is found in the upper Mississippi Valley, formed shortly after the last Ice Age,” they write in a piece for The Conversation. “As the environment warmed, 17-year-old crickets consecutively emerged in the area, generation after generation, after 13 years underground, until they were permanently shifted into a 13-year cycle.”
What can scientists learn from cricket mapping?
Some people consider the mass of insects to be one, but others welcome it as an awe-inspiring natural wonder. Some in the latter category even regularly travel across the US to areas where cicadas pop up to experience the sights and sounds and help scientists map the creatures.
“It’s great because you’re surrounded by thousands, maybe millions of these creatures who weren’t there the day before,” said Dan Mozgai, one of those citizen scientists. “It’s like an alien invasion, like being in a movie.”
A free app created at Mount St. Joseph University in Cincinnati called Cicada Safari and available for iOS and Android lets the cicada-curious record periodic cicada sightings. They can also record sightings on the Cicada Mania and iNaturalist websites, a joint initiative of the California Academy of Sciences and the National Geographic Society. Cicada mapping helps scientists verify the periodic life cycles of insects, as well as their relationships with each other, to gain a better understanding of biodiversity, biogeography and ecology.
Because Brood X occurs four years after Brood VI and four years before Brood XIV, and because the three broods are adjacent in parts of their geographic range, cicada trackers may see “laggards” of other broods this year.
“From a biological perspective, four-year laggards of each of these broods are interesting because they can cause gene flow between them,” explains the University of Connecticut. “From a practical standpoint, the four-year laggards of all these broods complicate mapping efforts because it can be difficult to assign populations to a brood.”
Laggards may confuse map efforts, but the university insists that a “misleading map is worse than no map at all.”
How long will Brood X last?
Mass mating takes at least three to four weeks. Shortly after, the newly hatched nymphs will crawl to the edge of the tree branches where the females laid their eggs, fall to the ground, and burrow for the next 17 years. And so the cycle begins again. Godspeed, Brood X.