The Spotted Lanternfly (Lycorma delicatula) is an invasive planthopper that has become a significant public concern across the eastern United States. The direct answer is that the spotted lanternfly does not produce loud, intentional, communicative sounds. Unlike many common insects, this pest lacks the specialized organs required for creating a distinct sound signal.
Biological Capacity for Noise Production
The spotted lanternfly is largely silent because it lacks the specialized structures found in sound-producing insects. Many insects, such as crickets and grasshoppers, use stridulation, rubbing two body parts together. Cicadas produce loud calls using tymbals, which are ribbed membranes on the abdomen buckled by muscle contractions.
The spotted lanternfly, belonging to the order Hemiptera, lacks both stridulatory organs and specialized tymbal membranes for intentional sound creation. This characteristic is common among many planthoppers. Its body structure is not engineered to broadcast signals through the air.
The Secondary Sounds of a Lanternfly Infestation
While the insects themselves are not vocal, large infestations create a noticeable ambient noise. This audible presence is a byproduct of their collective activity and feeding habits, not a form of communication. The most distinct sound reported is the dripping of honeydew, the sugary liquid waste excreted by the lanternflies after feeding.
When thousands of these pests feed on a single tree, they process large volumes of plant sap. The excess fluid is expelled as honeydew, which falls continuously from the canopy, creating a sound similar to light rain. This sticky substance also attracts other insects, like bees and wasps, whose buzzing adds to the overall auditory effect. Additionally, the sheer number of adult lanternflies flying or hopping can produce a soft, low buzzing or tapping noise as they bump into surfaces.
How Lanternflies Communicate
Since they do not use airborne acoustic signals, the spotted lanternfly relies on a multimodal communication system to locate each other and aggregate. One primary method involves chemical signaling, where they release semiochemicals, including pheromones, from their bodies and their honeydew. These volatile compounds help attract other lanternflies to form large aggregations.
The other main communication channel is through substrate vibration, where signals are transmitted through the host plant itself. Many hemipterans communicate by creating vibrations that travel through the stems and leaves. The spotted lanternfly is capable of sensing these vibroacoustic cues. Laboratory studies have shown that both nymphs and adults will actively move toward a source broadcasting a specific vibrational stimulus. This use of both chemical and vibrational signals allows them to coordinate their behavior effectively.