Your neighborhood, rural or urban, is likely filled with the sounds of insects at night. Tracking down the source of insect songs can be a challenge, but a rewarding one. Here are some common insects that broadcast under cover of darkness.
Field Crickets
Members of the genus Gryllus are the black, beefy, “field crickets,” found nearly everywhere, singing from ground level, often hidden in a burrow, beneath a stone, or other cover. Males chirp by rubbing a “file” on one wing against a “scraper” on the other. The front wings are modified not only to create sound, but amplify and broadcast it, too. A “calling song” attracts females from a distance. A softer “courtship song” woos her at close range; and a “rivalry song” rebuffs competing males.
Tree Crickets
These slender, delicate insects in the genera Oecanthus and Neoxabea barely resemble crickets. They sing from tall grass, berry canes, shrubs, and trees. Males have paddle-shaped front wings held erect when singing. Courtship involves the female feeding from glands on the male’s back, beneath his wings; and the male transfers a large gelatinous protein ball with his sperm packet. Both genders hear through a slot-like opening in each front leg, like other crickets and katydids.
Katydids
An enormous variety of katydids belong to the family Tettigoniidae. Also known as longhorned grasshoppers, they occupy a variety of habitats, from meadows to forests to arid deserts. Like the crickets mentioned above, males sing by rapid movements of the front wings against each other. Coneheaded katydids can be incredibly loud. The Common True Katydid sings a raspy “katy did, katy didn’t” song from the very tops of trees, sounding more frog-like than insect-like.
Cicadas
A few species of cicadas, family Cicadidae, sing after sundown, and/or are attracted to lights at night. The male cicada sings with a true percussion organ: a large muscle vibrates inside a hollow cavity in the abdomen, with a “lid” regulating the volume. There is one such organ on each side of the abdomen. Cicadas are related to leafhoppers.
More Information
Check out the website “Singing Insects of North America,” http://entnemdept.ufl.edu/Walker/buzz/, for all our species, including song recordings, maps, and pictures. Enjoy the serenade.