March 2008

Spotlight On…   Cicadas!

Cicada

For the past seventeen years, Brood X, a periodical cicada, has been living underground, feeding on tree sap waiting for this spring to arrive. As soon as the soil temperature reaches 64°, the nation’s largest emergence of insects will begin! Prepare yourself for this amazing natural phenomena with these resources.

What is a Cicada?

Adult periodical cicadas are plant-sucking insects that are approximately 1.5 inches long and have reddish-orange eyes, black bodies, and large amber wings. Periodical cicadas emerge once every 13 years in the southern states and once every 17 years in the northeastern states. There are twelve broods of 17-year cicadas; each brood appears in a different year. Brood X, the largest of all, will emerge in parts of fifteen states and will blanket most of southwestern Ohio. Each brood is comprised of three different species Magicicada septendecim, M. cassini, and M. septendecula. Pictures of each species can be found on the website of local cicada expert Dr. Gene Kritsky.

Additional reading:

The Periodical Cicada
William J. Gerhard

In Ohio’s Backyard. Periodical Cicadas
Gene Kritsky

Gene Kritsky, “They’re Back!: The Mount’s Periodical Visitors are Coming”, The Mount Magazine (Winter 2004): 2-4.

College of Mount St. Joseph: Cicada Watch 2004

University of Cincinnati Clermont College Biology: Periodical Cicadas

The University of Michigan Museum of Zoology Insect Division: Periodical Cicada Page

Ohio State University Extension Fact Sheet: Periodical and “Dog-Day” Cicadas

NationalGeographic.com: Quick Facts About Periodical Cicadas

The Life and Times of a 17-Year Cicada

The Life and Times of a 17-Year Cicada
Photo courtesy of Lester Daniels

Cicada nymphs spend the bulk of their life approximately eight to ten inches underground, sucking juices from tree roots. After seventeen years, mature nymphs starting to work their way towards the surface, waiting for the ground to soften and the soil temperature to reach 64°. After emerging, the nymphs climb on to nearby trees and molt into winged adults. The male cicadas then begin their frenzied, noisy search for a receptive female. After mating, the female deposits her eggs in the new growth of trees. Shortly thereafter, the adult cicadas begin to die off. In early August, the cicada eggs will begin to hatch and the nymphs will fall to the ground and burrow into the soil, where they will remain for the next seventeen years.

Additional reading:

The University of Michigan Museum of Zoology and the University of Cincinnati Clermont College Biology: Periodical Cicadas have more detailed explanations of the periodical cicada lifecycle.

The University of Nebraska Department of Entomology has compiled a gallery of photographs that documents each stage in the life of the cicada.

Strange but True

  • Magicicada Brood X, which will emerge in May, is the largest of the 17-year broods. For nearly six weeks, approximately five billion cicadas will blanket southwestern Ohio.
  • Their transparent wings are believed to filter out ultraviolet light. If you place a cicada wing on your skin before exposing your skin to the sun, it should protect your skin from tanning.
  • Each species has its own distinctive song, and each sings at different times of the day.
  • The song of just one periodical cicada can be as loud as nearly 90 decibels. That’s comparable to the sound of a blender or large truck driving down the street.
  • Not all cicadas have red eyes—in 1987, cicadas were found with white, pale blue, orange, and chocolate brown eyes.
  • Cicada Killer wasps capture and paralyze adult cicadas. The wasps then drag the bodies into deep burrows and lay eggs on them. When the eggs hatch, the baby wasps feed on the bodies of the stunned cicadas.

Sources: College of Mount. St. Joseph, University of Michigan Museum of Zoology, NationalGeographic.com , University of Cincinnati Clermont College, Encyclopedia Smithonsonian, and the University of Maryland.

Cicada Sounds

Singing Cicadas

The roar of noise in your backyard comes from male cicadas “singing” to attract females. They use drum-like membranes (tymbals) on their abdomen to produce this sound. Each cicada species has a distinct calling song, which can be easily distinguished if you listen carefully. You can listen to the chorus calls of the three species on National Public Radio’s website.

Delve more deeply into the science of cicada singing with one of the following articles from journals in our collection:

Henry C. Bennet-Clark, “How Cicadas Make Their Noise”, Scientific American 278 (May 1, 1998) 58-61.

Peter J. Marchland, “Jamming Cicadas: After Years Underground, These Insects Emerge on Cue and Sing in Concert”, Natural History 111 (June 2002): 36-39.

Susan Milius, “Cicada Subtleties: What Part of 10,000 Cicadas Screeching Don’t You Understand?”, Science News 157, no. 26 (June 24, 2000): 408+ .

T. Edward Nickens, “Insect Opera”, Audubon 102, i3 (May 2000): 25+.

Cicadas for Dinner?

Cicadas are eaten in Australia, Thailand, Japan, and Papua New Guinea and were considered a delicacy by the ancient Romans and Greeks. Like most other insects, cicadas are good source of vitamins and protein and are low in carbohydrates. (Most recipes call for using newly-hatched cicadas [tenerals] because their shells have not hardened.) A few adventurous local chefs plan to experiment with cicadas in the kitchen, but you don’t have to go to a restaurant to sample this local “delicacy.” Try your hand at cicada cookery with one of these recipes from an entomology graduate student at the University of Maryland.

Cicadas for Kids

The University of Maryland has prepared some suggestions for helping children enjoy cicadas. Salt the Sanbox has loads of fun resources for young scientists including a cicada hunt, puzzles, crafts, and booklists.

To pass the time while you’re waiting for cicadas to emerge from the ground, you can learn how to fold an origami cicada or color a picture of a cicada.

Try one of these resources from our collection:

Cicada Sing-Song
Densey Clyne

Cicadas and Aphids: What They Have in Common
Sara Swan Miller

Deborah Churchman, “Noisy Boys: Mating Calls of Crickets, Grasshoppers, Katydids and Cicadas”, Ranger Rick 29, no.9 (September 1995): 4-9.