How to Identify Periodical Cicadas

Every thirteen and seventeen years, insects called Periodical Cicadas climb from the ground to sing, eat, find a mate and then die. They emerge by the thousands and the males sing several tunes to attract the females. Different groups, known as Broods, emerge at different times. To identify Periodical Cicadas, use these guidelines and tips.

Difficulty: Moderate

Instructions

1. Get a field guide with pictures. An insect field guide should have color photographs with different types of cicadas including the Periodical Cicadas.

2. Find a map of the different broods. Search the Internet for brood maps of the different types of Periodical Cicadas. National Geographic has some excellent information on this insect (see link in Resources).

3. Look for cicada ground holes. The cicadas emerge from the ground through holes, called chimneys, and climb trees to shed their shells and begin the race to mate. The females lay eggs under the bark of branches and then die soon after. Once the cicadas emerge as nymphs, they fall and dig under the ground. Here they will live for seventeen more years feeding off the sap of tree roots.

4. Distinguish between different species of cicadas by looking at their eyes, size and wing shape. Most Periodical Cicadas have distinct red eyes, but there is one group that has white eyes. The typical dog-day cicadas have darker colored eyes. Many Periodical Cicadas also have red or orange outlines on the wings. The wings are different on each species.

5. Determine the species of the cicada. The Periodical Cicadas are different from the typical yearly dog-day cicadas. Three different periodical cicada species have a life cycle of thirteen years and four different species have a life cycle of seventeen years.

6. Check out the calendar when you first see cicadas. Periodical Cicadas come out in May and June whereas dog day cicadas come out in late June through August.

7. Listen to the song of cicadas. Search the Internet for sound files of these loud cicadas. Each species has a slightly different sound.

Tips & Warnings

• Buy a hand lens to help get a closer look at Periodical Cicadas.
• Although cicadas are edible by many creatures including humans, be careful of domestic pets eating too many. It can cause digestive upset in sensitive animals.
• Cicadas don't do harm to most established trees. But they can cause problems with shrubs, young saplings and diseased trees.

[kikkilu]

on 12/21/2007 if only someone could explain to me why, inside of the city of chicago this past summer (not some of the suburbs, where they emerged in droves) the 17-year cicada wasn't seen! it can't be from cement placed over the roots of trees at least 17 years old. we were in the forest preserves! in my childhood neighborhood, no cicadas emerged either, and nothing has changed with the trees. what does this mean? certainly, acid rain would fall in the suburbs too. so why didn't we see cicadas in almost every single chicago location???