Dealing with wasps is complicated and the recommendations for correct behavior are often contradicting. While it is clear that hectic movements should be avoided, there is uncertainty as to whether noise affects the insects. For this, it would be necessary for the yellow-black insects to be able to perceive them. So the question arises: can wasps hear?
Wasps are able to perceive pressure differences in the air and thus sound. However, they cannot hear like a human because they have no hearing in the strict sense. This perception is carried out by small hairs that are attached to the antennae.
However, this auditory perception is subject to many restrictions and that’s why you will learn how wasps hear and why it is not comparable to our hearing in this article. We also clarify whether you can drive away wasps with sounds or ultrasound.
Wasps and sound: What does hearing mean?
Sound is the transmission of pressure differences in a certain medium. In our normal environment, this medium is the air and the pressure difference is a vibration that is transmitted in the form of a wave.
An oscillation can be triggered by various objects. Air particles have to be merely briefly compressed (as with a tuning fork, a guitar string, the vocal cords, etc.). The properties of the material and the energy released determine the pitch and volume.
Hearing is recognizing and interpreting these sound waves. While in humans this is always done with the help of an eardrum (a thin stretched membrane), insects have different auditory organs.
Do wasps have ears?
Wasps do not have ears to perceive sound. However, they have fine hairs that sit on the second antennae element and detect pressure differences. The collection of fine sensory hairs is called Johnston’s organ.
Compared to other insects, wasps do not have a tympanic organ. This is a small membrane that can sit on different parts of the body (often on the legs) and works just like an eardrum. This “ear” is found in other insects such as grasshoppers and crickets.
What can wasps hear?
Wasps are able to perceive sound waves and therefore can hear. The pressure differences in the air are recorded by the Johnston organ and then interpreted. The perception is limited to the close range.
The lack of an ear drum severely limits auditory perception. While a membrane can record vibrations very precisely and in detail, this is only the case to a limited extent with sensory hairs sitting in the air.
The hairs are deflected indirectly via the deflection of the antenna flagella, which, however, cannot produce the same precise representation as a membrane.
This structure of the Johnston organ limits the frequency range in which wasps can hear to a maximum of 500 Hz. This limitation has not yet been precisely determined but results from the functioning of the organ, which is very similar to the related bees (where these values were determined).
In addition, the hairs detect not only sound but all forms of pressure differences in the air. Vibrations of the environment are an important indicator for the insects, whether there are danger or prey in the vicinity.
These sources of interference, limitations, and sensory overlaps severely limit the hearing of wasps.
There is no perception of sound in wasps, as in humans.
The hearing ability of wasps also decreases with increasing distance. This also makes sense, because while information about what is happening in the vicinity is of vital importance, noises and vibrations at a greater distance are irrelevant.
How do wasps communicate?
Wasps communicate with each other in different ways. Primarily, they use pheromones and tactile communication.
The transmission of information is quite complex and many parts have not yet been researched in detail. However, social wasps in particular are likely to have an extensive scheme of communication strategies.
Communication via sound does not seem to play a major role here. Here other insects with better hearing are positioned much wider and use this path much more intensively.
Insects that are actively making noises can also hear well.
Still, recent studies suggest that wasps make rhythmic sounds to share information about food sources in the area. To do this, they drum certain parts of the nest with their abdomen to inform (and activate) other workers.
Wasps can communicate via sound but do so in a very restricted and limited area that is predetermined by their hearing organ.
Repel wasps with sounds
The perception of sound could help drive wasps away with certain noises and tones. The sound of a natural enemy, an unknown threat, or a sound that is “unpleasant for wasps” could be a good means of chasing them away.
However, the effectiveness of such measures fails due to the wasps’ limited perception of sound.
There are no special tones generated by their enemies that could be used. Unfamiliar and loud noises also have no influence on their behavior.
In addition, it only makes sense to drive away wasps with noise if there are no impairments for humans. The tones should therefore be in the range of infrasonic or ultrasonic waves.
Wasps and ultrasound
Ultrasound describes frequencies above 20 kHz (20,000 Hz) and thus outside the audible range for humans. These tones occur regularly in the animal kingdom and are used not only for communication (dolphins) but also for localization (bats).
There are numerous ultrasonic devices that claim to have a deterrent effect on pests. Models against mice, martens, and mosquitoes are particularly widespread. But there are also “special” ultrasound devices against wasps.
It applies to all animals that they first have to perceive the ultrasound before an effect can even occur in the second step.
The wasps’ hearing organ is limited to a frequency range of up to 500 Hz. Thus, for wasps (as for most pests) it is true that they cannot detect ultrasound. The devices can therefore have no effect at all.
Even with insects that can perceive these high frequencies, effective control is not guaranteed. The devices produce little to no effect and are not based on any scientific basis.
This lack of effectiveness has even been proven in various studies and confirmed several times. Numerous studies were carried out, especially for insects such as mosquitoes, and no effect was found.
Ultrasonic devices against pests (like wasps) are a marketing tool and unfortunately not effective.
The investment should therefore be avoided. The money can then be used for more effective repairs to the house (sealing cracks and structural damage) and other preventive measures against a wasp plague (glass containers for a picnic).
Attract wasps with sounds
Sitting outside in the summer and being chased by wasps is an impression that is made regularly but not related to noise.
Wasps do not react to our voices and cannot assign them either. So they don’t come out as soon as they hear us and neither do they disappear when we yell at them.
In the same way, they do not become aggressive if someone is surprised by them and produces a scream of fear. The movements of the arms and the entire body determine how threatened the wasp feels and whether it stings or not.
