Do wasps make noise? Yes, the sounds they produce range from the mechanical byproduct of movement to intentional communication. The most common noise is the continuous low-frequency hum created during flight. Other distinct sounds serve as warnings of distress or indicate construction activity near their nest. Understanding the source of these noises offers insight into the wasp’s current behavior and intent.
The Biology Behind the Flight Buzz
The buzzing sound is primarily a mechanical consequence of the wasp’s flight mechanism. Wasps, like other flying insects, create this noise through the rapid, alternating contraction of their flight muscles within the thorax. These muscles cause the thorax to vibrate, which powers the flapping of the four wings. The sound is essentially the byproduct of this rapid oscillation.
The frequency of the wing beat determines the pitch of the buzz heard by humans. Wasps are four-winged insects, and they flap their wings at a slower frequency than two-winged insects like flies, resulting in a deeper, lower-pitched sound. For species like the Cicada Killer Wasp, the fundamental frequency of the buzz can range between 150 to 210 Hertz. This sound is not intentionally communicative when the wasp is flying, but it effectively announces its presence.
Sounds of Warning and Distress
Wasps produce distinct, non-flight noises when they feel threatened, cornered, or are communicating an alarm to their colony. These defensive sounds often involve short, rapid bursts of buzzing, produced while the wasp is stationary and its wings are folded. This type of defensive vibration is generated by activating the thoracic muscles at a higher frequency than during normal flight, resulting in a higher-pitched, more urgent sound.
Another distinct warning sound is stridulation, where the wasp rubs one body part against another, similar to a cricket. Many species, including velvet ants, use this method to create an audible squeaking or chirping sound under stress. This auditory signal acts as a form of aposematism, warning a potential predator that a sting is imminent. Social wasps may also use a coordinated, loud wing-beating display when an intruder approaches the nest, creating a collective noise that serves as an organized threat display.
Audible Signs of Nest Activity
Even when a wasp is not flying or actively defending itself, it can still produce sounds related to its daily maintenance and construction tasks. The most common noise associated with a nest is the faint scraping or rasping sound of the wasps chewing wood fibers. Wasps mix these chewed fibers with saliva to create a paper-like pulp, which they use to construct their characteristic gray nests.
This chewing noise is only audible when a person is very close to the nest structure. Other subtle sounds can be heard from inside an active nest, such as faint rustling or a low crackling. This noise is caused by the movement of adult wasps and developing larvae inside their paper cells, especially when adults feed the young. Certain species of Vespula wasps have larvae that produce a croaking or rasping sound by scraping their mandibles against the cell walls, possibly signaling hunger.