Why Do Cicadas Make So Much Noise Understanding Cicada Sounds

If you've ever spent a summer afternoon in a wooded area or suburban backyard, you’ve likely heard the unmistakable, pulsing chorus of cicadas. Their sound—ranging from a high-pitched whine to a rhythmic buzz that can reach over 100 decibels—is one of the most distinctive natural phenomena of warm climates. But what exactly causes this intense noise? And why do cicadas invest so much energy into producing it? The answer lies in biology, evolution, and an intricate system of acoustic communication that has developed over millions of years.

Cicadas are not just loud; they are among the loudest insects on Earth. Some species, like the annual dog-day cicadas and periodical Magicicada species, produce calls that can drown out lawn mowers and even rival the volume of a chainsaw. This article explores the science behind cicada sounds, their purpose in nature, and how their behavior impacts both ecosystems and human experiences.

The Biology Behind Cicada Noise Production

Unlike crickets or grasshoppers, which create sound by rubbing body parts together (a process called stridulation), cicadas generate noise using specialized organs called tymbals. These are ribbed, drum-like structures located on the sides of the male cicada’s abdomen. When muscles rapidly contract and relax, the tymbals buckle inward and snap back, producing a clicking sound. Thousands of these clicks per second combine to form the continuous, buzzing call we hear.

The hollow abdomen of the cicada acts as a resonating chamber, amplifying the sound significantly. This biological design allows males to broadcast their presence across long distances—sometimes up to a mile—making them highly effective at attracting mates despite dense foliage or competing noise.

“Cicadas are essentially living speakers. Their anatomy is fine-tuned for maximum sound output with minimal energy cost.” — Dr. Jameson Foster, Entomologist at the University of Illinois

Females do not possess tymbals and are largely silent. Instead, they respond to male calls by flicking their wings, creating a subtle auditory signal that guides the male toward her. This precise acoustic dialogue ensures reproductive success while minimizing unnecessary movement and exposure to predators.

Purposes of Cicada Sounds: Mating, Survival, and Synchronization

The primary reason male cicadas sing is to attract females for mating. However, their vocalizations serve several other critical functions:

• Mate attraction: Each species has a distinct call pattern, allowing females to identify suitable partners and avoid hybridization.
• Reproductive timing: In periodical cicadas (like the 13- or 17-year broods), synchronized emergence and calling ensure mass mating events, overwhelming predators through sheer numbers—a strategy known as predator satiation.
• Species recognition: Calls vary by frequency, rhythm, and duration, helping maintain genetic boundaries between closely related species.
• Territorial signaling: Males may adjust their calling intensity or timing to avoid direct competition with nearby singers.

Tip: If you're recording cicada sounds, use a directional microphone and record during midday when temperatures peak—this is when most species are most active.

Differences Between Annual and Periodical Cicadas

There are two main types of cicadas in North America: annual and periodical. While both are loud, their life cycles and calling behaviors differ significantly.

Feature	Annual Cicadas	Periodical Cicadas
Lifecycle	2–5 years (overlap generations)	13 or 17 years (synchronized)
Emergence Pattern	Every summer, staggered	Mass emergence every 13/17 years
Noise Level	Moderate to loud (80–90 dB)	Extremely loud (up to 105 dB)
Vocal Duration	Weeks to months	3–6 weeks per generation
Species Example	Neotibicen spp.	Magicicada septendecim

Periodical cicadas, due to their synchronized life cycles, create a more intense acoustic environment. When billions emerge simultaneously, their collective calls form a near-constant wall of sound. This “chorusing” effect increases mating efficiency and reduces individual predation risk.

How Environment Influences Cicada Choruses

Temperature plays a major role in cicada activity. Most species only begin calling when ambient temperatures exceed 77°F (25°C). As the day heats up, especially between 10 a.m. and 3 p.m., their calls become louder and more frequent. Humidity and sunlight also influence singing patterns—dry, sunny days typically yield the most intense choruses.

In urban environments, cicadas may alter their calling times or frequencies to overcome background noise. Studies have shown that some populations shift to higher-pitched calls in cities to avoid masking by low-frequency traffic sounds—a phenomenon known as the “urban pitch shift.”

Real Example: The Great Eastern Brood Emergence of 2024

During the historic dual emergence of Brood XIII (17-year) and Brood XIX (13-year) cicadas in spring 2024, residents across Illinois, Indiana, and Missouri reported unprecedented noise levels. In Chicago suburbs, sound meters recorded peaks above 98 decibels near wooded areas—equivalent to standing next to a running motorcycle.

Local ecologists noted that despite public complaints about the noise, bird and squirrel populations showed temporary declines in predation during the emergence, suggesting that the overwhelming abundance of cicadas diverted attention from other prey. Additionally, researchers used mobile apps and citizen-submitted audio recordings to map species distribution based on call signatures, demonstrating how cicada sounds serve as valuable ecological indicators.

Understanding Cicada Sound Patterns: A Step-by-Step Breakdown

To fully appreciate how cicadas communicate, consider the sequence of a typical mating call:

1. Warm-up phase: Male begins with short, sporadic clicks as body temperature rises.
2. Calling song: Once warmed, he produces a sustained, species-specific melody lasting several seconds.
3. Pause and listen: After each phrase, he stops briefly to detect wing-flick responses from females.
4. Aggressive response: If another male encroaches, he may switch to a faster, more erratic call to assert dominance.
5. Approach and courtship: Upon detecting a female response, he transitions to a softer, pulsing courtship call.
6. Mating: If successful, the pair mates, and the female later deposits eggs into tree branches.

This structured vocal behavior highlights the sophistication of insect communication—far beyond simple instinctual noise.

Frequently Asked Questions

Are cicadas harmful because of their noise?

No. While their sound can be startling or disruptive, cicadas pose no danger to humans. They do not bite, sting, or carry diseases. The noise is purely a reproductive behavior and subsides after a few weeks.

Can cicada sounds damage hearing?

Prolonged exposure to sounds above 85 dB can contribute to hearing loss. Though cicadas can reach 100+ dB, most people are not close enough for long enough to suffer harm. Using ear protection during extended outdoor work in heavy infestation zones is advisable.

Why do some years seem louder than others?

Loudness varies based on cicada species present, population density, weather conditions, and whether a periodical brood is emerging. Years with overlapping broods or favorable breeding conditions result in far more intense choruses.

Tip: To reduce perceived noise, plant dense shrubs or install water features—the sound of flowing water can mask high-frequency cicada calls.

Conclusion: Embracing the Symphony of Summer

The deafening chorus of cicadas is not random noise—it’s a complex, evolved language of survival and reproduction. From the mechanics of tymbal vibration to the synchronization of billion-strong emergences, every aspect of their sound serves a purpose. Rather than viewing their calls as a nuisance, we can learn to appreciate them as a sign of ecological health and seasonal rhythm.

Next time you hear that pulsing summer soundtrack, take a moment to listen closely. You might begin to distinguish individual calls, recognize patterns, or simply marvel at nature’s ingenuity. The cicada’s song is fleeting—lasting only weeks—but its impact on the ecosystem and our sensory experience of summer is profound.

💬 Have you experienced a major cicada emergence? Share your story or favorite cicada fact in the comments below—let’s celebrate the sound of summer together!