Updated on July 2nd, 2024
At night, when the world is enveloped in darkness, a symphony of sounds emerges from the hidden corners of your yard. These sounds are not the lullabies of silence; they are the nocturnal serenades of insects.
Allow me, Dr. Killigan, to help you identify the night-time sounds you hear and enlighten you about these winged insects that make their presence known in the darkness.
What insects make noise at night?
There are three prominent nocturnal insects that produce soothing night-time sounds: crickets, katydids and cicadas. The gentle chirping of crickets, the melodic serenades of katydids and the rhythmic buzzing of cicadas in the distance can create a calming ambiance that helps individuals relax and fall asleep.
Crickets: The chirping sounds they make
Crickets are the true minstrels of the night, producing sound through a process called stridulation. You see, male crickets have specialized structures on their wings called stridulatory organs. These organs consist of a scraper-like structure on one wing and a serrated ridge on the other wing. When a male cricket wants to produce a chirping sound, he rubs the edge of one scraper wing against the serrated ridge of the other wing. This rapid movement and friction between the scraper and the serrated ridge produces the familiar chirping sound associated with crickets.
Crickets: Why they make this noise at night
You may wonder why these insects perform such a captivating concert. I’ll tell you: It’s all for the sake of love. Male crickets employ their melodies to communicate their presence and entice and attract the attention of their potential mates. Taking center stage under the cover of darkness, they hope that they’ll be heard and noticed by females.
Katydids: The complexity and variation of sounds they make
Katydids, like crickets, also produce sound through stridulation. Whereas crickets produce stridulation through the movement of their wings, katydids—including giant katydids—produce it by rubbing their wings together. Katydids wings have specialized structures called stridulatory veins. These veins contain rows of small teeth-like structures, which are located on the underside of their forewings. When a katydid wants to produce sound, it moves its wings in a rapid and repetitive motion. As the wings rub against each other, the teeth on one wing slide along the veins of the other wing, creating the distinctive sound associated with katydids.
This process of wing-rubbing—or stridulation—allows katydids to produce a wide range of sounds, from soft and subtle to loud and piercing. The complexity and variation in their songs is what sets them apart. Each species of katydid has its own unique song pattern, enabling them to identify and locate potential mates and establish their presence in their environment.
Katydids: Why they make this noise at night
Katydids make noise primarily for communication purposes, particularly during the mating season. When it's time to woo a mate, male katydids unleash a cacophony of sounds that can be heard far and wide. These loud and distinctive sounds serve as a way to attract females and establish territory. The specific patterns and frequencies of their calls are species-specific, allowing individuals to identify and locate potential mates of the same species (and avoid mating with individuals of other species).
The variety of katydid calls are believed to convey important information about the male's fitness and desirability as a potential mate. Females use these acoustic signals to assess the suitability of males for reproduction.
In addition to mating calls, katydids may also use sound to communicate danger or engage in territorial disputes with rival males. Their vocal repertoire extends beyond matters of the heart.
Cicadas: The buzzing sounds they make
Male cicadas have a specialized organ on the side of their abdomen called a tymbal. This tymbal consists of a pair of ribbed membranes that can be rapidly and repeatedly flexed. By contracting and relaxing the muscles associated with the tymbals, cicadas make these muscles vibrate and thus produce a buzzing sound.
To amplify this sound, cicadas have a hollow body cavity—called the resonating chamber—which acts like their own built-in speaker system to help project their sound and make it more audible. The vibrations produced by the tymbals are channeled through this resonating chamber, transforming the vibrations into the unmistakable noises we associate with cicadas.
Note: The sounds produced by cicadas can vary depending on the species and the specific circumstances. Some cicadas produce clicking or ticking sounds, particularly during courtship or territorial displays, though the characteristic buzzing noise is more commonly associated with the collective chorus of multiple cicadas.
Cicadas: Why they make this noise at night
Cicadas—including giant cicadas—make noise primarily for two essential reasons: mating and communication. The males, in their relentless pursuit of love, serenade the females with their loud, distinctive calls, each species boasting its own unique mating song.
In addition to mating, cicadas also use their calls as a means of communication and establishing territorial assertion. The loud buzzing chorus created by a group of cicadas can serve to deter potential predators and signal the presence of a united front. Moreover, it aids in delineating boundaries between different cicada territories, ensuring harmony within their buzzing realm.
Conclusion: A symphony in the dark
As dusk falls and night embraces the landscape, the air fills not with silence but with a symphony composed by nature's own musicians. In this nightly orchestra, crickets, katydids and cicadas are not merely background noise; they are the stars of the show, each playing a crucial role in the nocturnal life of your garden. These sounds—whether the chirping of crickets, the songs of katydids or the buzzing of cicadas—are all part of a complex communication system designed for survival and reproduction.
Understanding the purpose behind these sounds can transform how we perceive and experience our nightly surroundings. Instead of a mere cacophony, we can begin to appreciate a concert of calls that has been perfected over millennia.
Next time you find yourself enveloped in the darkness of a warm night, I encourage you to pause and listen. Let the hidden world of insects remind you of the vibrancy and complexity of life that continues unabated while the world sleeps.
At Dr. Killigan's, we strive not only to inform but to enhance your appreciation for the often overlooked aspects of nature’s beauty. May your nights be filled with peaceful listening and a deeper respect for these diligent nocturnal artisans.
