Cicadas are a familiar presence during warmer months, recognized by their distinctive and loud sounds. These insects, part of the superfamily Cicadoidea, generate a unique auditory experience. Their calls are a defining feature of summer landscapes.
The Distinctive Sound of Cicadas
The sound produced by cicadas is described as buzzing, whirring, or droning. This sound varies in intensity and rhythm by species; some produce a high-pitched whine, while others create a pulsating rattle. Cicadas are among the loudest insects, with calls reaching 80 to 120 decibels at close range. A collective chorus often measures around 88.5 dBA, comparable to a lawnmower or vacuum cleaner. Some African species can even reach 107 decibels, nearly as loud as a chainsaw.
Different cicada species produce slightly varied sounds, which helps them distinguish each other within their diverse populations. For example, Magicicada cassini is known for a loud, high-pitched buzz that swells and ebbs, sometimes compared to an electric string trimmer. In contrast, Magicicada septendecim may produce a howling sound that some describe as resembling a whistling tea kettle or even saying “pharaoh.” The large number of cicadas emerging simultaneously, especially periodical broods, contributes to their collective chorus’s volume.
The Purpose Behind the Calls
Cicadas primarily produce sounds for communication, mainly for mating. Male cicadas generate loud calls to attract females of their own species, ensuring successful reproduction. These species-specific songs allow different cicada populations to coexist without interbreeding.
Beyond the general mating call, cicadas utilize different types of songs for specific communicative purposes. Calling songs are broadcast to attract mates from a distance, often forming large choruses that amplify sound and deter predators. Courtship songs are produced during closer-range interactions between a male and a female just before mating. Cicadas also emit distress calls or disturbance squawks when handled, threatened, or captured.
How Cicadas Create Their Unique Sound
Cicadas create their sounds using specialized organs called tymbals, found on the abdomen of male cicadas. Each male cicada possesses a pair of these ribbed, drum-like membranes. Sound is produced when muscles rapidly contract and relax, causing the tymbals to buckle inward. This buckling action creates a series of rapid clicks.
Tymbals buckle 120 to 480 times per second, producing a continuous buzzing sound to the human ear. The clicks are then amplified by large, hollow air sacs within the cicada’s abdomen, which act as resonant chambers. This amplification allows these relatively small insects to generate sounds that can travel long distances, effectively aiding their communication and reproductive success.