The arrival of summer in the midwest this year aligns with the much anticipated emergence of the notorious, and celebrated, 17-year cicada. While this large, vociferous insect’s arrival is always significant due to its infrequency, this year in parts of America’s Midwest two of the overlapping broods will emerge  at once. While some dread the cicada’s arrival for their hungry, buzzing ways, others laud the synchronicity of their short-lived stay above ground and their important contribution to local ecosystems. 

The Periodical Cicada

The 17-year cicada, a type of periodical cicada, gets its name from their lengthy life cycle (most of which is spent underground) and the predictable timing of their mass emergences. Although the brood in Wisconsin (brood XIII) emerges every 17 years, other species of periodical cicadas emerge after only 13. In fact, there are 7 different species of periodical cicadas, often sharing physical characteristics and geographic locations. Different from the blackish-green annual cicada whose distinctive buzz can be heard throughout mid and late summer, their periodical cousins are black with orange wings and legs, and red eyes.

Why the Great Emergence?

Likely developed as a unique evolutionary strategy, periodical cicadas emerge en masse from their nymphal stage underground after 13 or 17 years in order to complete their life cycle in a few short weeks, molting into their adult form, mating, and laying eggs. As herbivorous, non-poisonous insects with few defenses, scientists hypothesize their mass emergence is a strategy of over-abundance; in such large numbers, predators quickly become satiated on a small portion of the total population, allowing the rest to finish out their lifecycle. This grand entrance not only benefits hungry predators, but also adds nutrients back to the soil as their bodies return to the earth, and increases oxygen flow through the soil as nymphs dig down to eat from tree roots.

Cicada Broods

Although annual cicadas are found worldwide, periodical cicadas are unique to North America. Concentrated in the central and eastern portions of the US, periodical cicadas are divided into 15 broods–regional groupings of multiple species of periodical cicadas who have a synchronized timing of emergence. The 17-year broods tend to live  in a more northerly location, while the 13-years prefer the south. In some places like Iowa and Illinois, these broods overlap and can occasionally emerge simultaneously.

Image Source: Liebhold, A. M., Bohne, M. J., and R. L. Lilja. 2013. Active Periodical Cicada Broods of the United States. Active Periodical Cicada Broods of the United States. USDA Forest Service Northern Research Station, Northeastern Area State and Private Forestry.

What to Expect in Wisconsin

Southern Wisconsin is home to Brood XIII, one of the 17-year cicada broods emerging this year that won’t be seen again until 2041. According to the Wisconsin DNR, the first sightings were confirmed on May 17th in the Lake Geneva area. If you are lucky enough to encounter a periodical cicada in our state, it will most likely be the species Magicicada septendecim. Brood XIII will continue to emerge through the beginning of the June and is expected to be gone by the end of the month. While we won’t see any in the Madison area, this was not always the case. A once periodic resident of the area, the last known recorded sighting of these cicadas in the area was roughly 70 years ago.

Threats to Cicadas

It can be easy to assume that animals with large populations are safe from environmental and human-caused threats. However, habitat loss is as serious a concern for these creatures as any other animal sharing the world with humans. Periodical cicadas get their food and make their homes in the deciduous forests of North America, both above ground feeding and laying eggs, and below ground in their long stay as a nymph. As trees are cut down, pesticides sprayed, and soil paved over, periodical cicadas become unable to complete their life cycle. Additionally, Like other insects, a warming climate can  disrupt their periodicity.

Engage with Cicadas

With that said, the time is nigh to enjoy our buzzing neighbors! Visit the Cicadapalooza Pop-up Event on June 8th from 12-4:30 at the Lake Geneva Public library for a fun, family-friendly and free pop-up event. Enjoy tours and talks by UW-Madison entomologists, cicada merchandise, food, and more!

For More

• Checkout The Buzz About Wisconsin’s Periodical Cicadas Webinar featuring UW extension entomologist PJ Liesch to learn more about the biology and ecology of the periodical cicadas in Wisconsin.

• Learn more about the biology of periodic cicadas and listen to their buzz here.
• Record a cicada sighting with iNaturalist or the Cicada Safari.

In Case You Missed It…

News from Nature Net Members​​

Welty Environmental Center	Olbrich Botanic Gardens	Dane County Parks
Welty is looking for volunteers interested in helping with their The Sky’s the Limit STEM Camp, a summer camp hosted in collaboration with UW-Madison Nelson Institute Center for Climatic Research. This camp provides autistic youth with safe and positive experiences in outdoor, hands-on learning. Please reach out to Michael Notaro (mnotaro@wisc.edu) for more information.	Interested in beautifying your garden and supporting pollinators? Olbrich Botanic Gardens is hosting their online only Summer Pollinator Plant Sale from June 4th-June 21st, with plant pickup on June 26th. Attract important pollinators with nectar-rich perennials ranging from milkweeds to delphiniums! Learn more and shop the sale here.	This month, Dane County Parks is kicking off their summer ‘Parks Alive’ series, hosting free evening events at local parks with fun, family-friendly activities to build community. The season begins with Allied Park on June 10th,  followed by Aldo Leopold Park on June 11th, and Meadowood Park on June 12th. Learn of all the Parks Alive events here. ​

For Families:	For Educators:	Upcoming Events:
The Nice Age Trail at the Madison Children’s Museum is now open and ripe for exploration! Inspired by nature and designed to teach kindness, this exhibit is the biggest indoor addition to the museum in seven years. The Nice Age Trail offers an interactive experience that invites kids to explore four Wisconsin seasons across four habitats–and the world of the animals who live there.  Entrance fee is included in admission cost to the museum. Learn more here.	The end of May marked a momentous occasion: Madison hosted the world’s largest gathering of children and nature leaders for the Children & Nature Network’s Nature Everywhere Conference. Over 600 people from around the world came to celebrate work focused on providing equitable access to nature to children from Mary 28-31st. Learn more about the Children & Nature Network here.	With summer in full swing, opportunities to engage with our local member sites. From regular work days to manage healthy native plant communities at places like UW Arboretum, Lussier Family Heritage Center, and Schumacher Farm Park, along with guided education tours at favorite spots like Cherokee Marsh, there are many ways for everyone to get involved with nature this season. Stay tuned by checking out the Nature Net calendar.

Nature Net News: Funding & Content Creation