Cicadas, the Summer Sound of the Vineyards

By Jose Luis Gallego, environmental communicator (@ecogallego)

During the midday hours, a very particular soundtrack fills the vineyards: the sound of the cicadas, known for having one of the most stridently monotonous calls in nature. 

Concealed amid the branches of the trees (almond, carob, olive, pine, holm oak, and others) growing around the vineyards, the cicadas take advantage of high summer temperatures to tirelessly repeat their monotonous yet powerful song. Despite the ubiquitous nature of the sound, most of us are rarely curious about figuring out where it is coming from exactly or locating its source. 

A cicada perched on a tree trunk (photo: Jose Luis Gallego)

If we did decide to do so and very slowly approached the trunk of the olive or almond tree where we think the cicada might be, we would be in for an enormous surprise – cicadas can be more than six centimetres in length, making it one of the largest insects of all Iberian fauna. Yet spotting them isn’t easy. First, because the instant they notice our presence, cicadas will automatically stop singing. And second, because their colouring is almost identical to the branches and trunk of the tree, making them practically invisible once they fall silent. 

Beyond their enormous size and cryptic colouration, the common cicada, scientifically classified by the Latin name Cicada orni, is also surprising for the way it produces its sound – a sound that isn’t actually a “song”. Although I took some poetic license earlier, cicadas – like crickets – do not actually sing. And, like their nocturnal kin, only males produce this unmistakable sound. 

Cicadas produce their characteristic buzzing sound with their bodies, not their mouths. They do so by inflating and deflating the membrane of the air sacs located on their abdomen, which entomologists accurately refer to as “tymbals”, because that is, in fact, what they are – and powerful ones to boot. 

A pair of cicadas on a tree

The continued intervals and potent enthusiasm of this characteristic sound – one that can be very irritating to the human ear, even unbearable to some people – accelerate and increase as temperatures rise.  This is why we perceive the sound of the cicadas as more intense during heat waves, which are becoming more frequent and extreme as a consequence of climate change. And in fact, it is. 

Yet this unremittingly strident sound, this apparently monotonous cacophony, is full of subtle sound variations that our irritated ears cannot perceive, but which the insects use to send a host of different messages. 

Male cicadas will produce different sounds depending on whether they are marking their territory in front of a rival or trying to attract a female mate. In the latter situation, these amorous messages can reach a volume that is so potent that, under favourable conditions, females will be able to hear it more than one kilometre away. But let’s not assume that all aspects of this amorous communication fall to the male. 

For a female to hear the proposals of her potential mate across such great distances, evolution has endowed her with a complementary tool: a sophisticated eardrum that is far larger and more finely attuned than that of the male. 

We hope that knowing the many fascinating facets of this unusual denizen of our fields – commonly found in the woodlands around vineyards – we’ll feel greater admiration and curiosity when we hear the powerful sound of the cicadas’ tymbals.  As we now know, it is a sound full of secrets, including some of nature’s most enthusiastic and energetic declarations of love.