July 23, 2010

Summer Cicadas

by Susan Post

Late evening of the hot days of summer is the perfect time to hear the loud drone of male cicadas. Even during classical times the fact that only male cicadas produced sound was well known, leading to the chauvinistic comment—"Happy are the cicadas for they all have voiceless wives."

After spending anywhere from one to six years underground as a nymph, cicada males loudly announce their arrival upon the scene. The call is produced, not by rubbing wings or legs together, but by muscles vibrating a pair of drum-like membranes in the cicada’s thorax. An air cavity acts as a resonator and connects to the outside through a pair of tiny holes called spiracles.

While many of us may be familiar with the dog day or annual cicadas found in our yards—prairies also support cicadas. People who've seen this insect in high quality prairies say they “fly up like partridges when disturbed.” The adult prairie cicada's body is large, approximately one and half to two inches long and brownish yellow with conspicuous brown and white markings. Prairie cicada nymphs, instead of feeding on the roots of trees like their city and forest cousins, prefer to suck the sap of the long roots of prairie dock and compass plant.

Whether you hear the drone of the cicadas in your backyard or on the prairie, recognize it for what it is and enjoy this brief, poignant, noisy love serenade of summer.