Stink bugs, belonging to the insect family Pentatomidae, are commonly recognized for their distinctive shield-like shape and the unpleasant odor they can release. These insects, particularly the brown marmorated stink bug (Halyomorpha halys), have become a widespread presence in many regions. Originally from East Asia, they arrived in the United States accidentally in the mid-1990s and have since established themselves across various areas. While often seen as a household nuisance, especially as they seek warmth indoors during cooler months, their general characteristics extend beyond their odor and appearance.
The Subtle Sounds of Stink Bugs
Stink bugs are not known for producing loud or easily noticeable sounds, but they can generate subtle noises in specific situations. These insects can produce a faint buzzing, a distinct clicking, and even vibrational “songs.” The buzzing noise is primarily associated with their flight, which can sometimes be surprisingly loud despite their small size.
The clicking sound often occurs when stink bugs land on hard surfaces. This noise results from a combination of their physical impact and the folding of their tough exterior forewings, which act as protective coverings for their hind wings. The sound is more pronounced on hard surfaces like walls or countertops. Stink bugs also engage in vibrational communication. These vibrational signals are intended for communication within their species rather than for human detection.
How Stink Bugs Produce Sound
The buzzing sound produced during flight originates from the rapid movement of their hind wings. The forewings, which are thicker and tougher, primarily serve as a protective layer for the delicate hind wings and contribute to the clicking sound upon landing.
Beyond flight, stink bugs produce sounds through vibrations of their abdomen. These vibrations are then transferred to the surface the stink bug is on. This method of sound production is a form of substrate-borne vibration, meaning the sound travels through the material the insect is in contact with, rather than through the air. This mechanism differs from stridulation, where insects rub two body parts together to create sound. Instead, stink bugs utilize their abdomen to create these subtle vibrational signals, which are then transmitted through their legs and the surface they occupy.
The Purpose Behind Stink Bug Sounds
The sounds produced by stink bugs serve various behavioral functions, primarily for intraspecies communication. One significant purpose of these sounds is during mating rituals. Male stink bugs use vibrations to attract and locate nearby females, often described as a “song.” These vibrational signals, orchestrated by the male’s abdomen, are transmitted through the substrate and can elicit a response from a receptive female. If a female is nearby, she may reply with her own vibrational song, leading to an exchange of signals until the pair can find each other.
Stink bugs also use sounds as distress signals or warnings. When disturbed or threatened, the buzzing and clicking noises they produce indicate agitation. While their primary defense mechanism is the release of a foul odor, these subtle sounds can also play a role in their response to perceived danger. These communication methods are not intended for human perception and are most effective for short-distance interactions between individual stink bugs.