In the Museum of Natural History in Ljubljana, the Slovenian archive of animal sounds functions within the Invertebrate Department, one of its activities being research into insect bioacoustics, with an emphasis on true bugs (Heteroptera) and singing cicadas (Homoptera: Cicadoidea).

The characteristic songs of 9 cicada species are presented, with 8 of them living in Slovenia, while the species Cicadetta mediterranea inhabits the coast of southern Istria near Pula (Croatia).

Some smaller species’ songs consist of high tones passing over into ultrasound (e.g. Tettigetta brullei). This, however are difficult to detect with the naked ear. “The ultrasound detector” (UsD, in our case the Ultra Sound Advice S-25 detector) with a directional microphone (Mic), helps us locate small cicadas even up to 50 m away.

The recordings presented herewith were made with a Telinga Pro III directional microphone and a DAT recorder (Sony TCD-D3 or TCD-D7) (DAT) during the summers of 1994/95 in Slovenia and, in one case, with other recording equipment (Cicadetta montana) in Russia. The authors of the recordings are Matija Gogala (Ljubljana) and Andrej V. Popov (St.Petersburg, Russia). The sonogram was made with Signalyze 3.0 software.

Owing to the high frequencies in some species’ songs, the audio files have a sampling frequency of 48 kS/s. If you cannot play the sound with the same rate, lower the sampling frequency. Thus, the song will be slowed down a little and lowered.

Authors:

• Prof Dr  Matija Gogala
• Prof Dr Andrej Popov
• Dr Tomi Trilar

The three cicada species, which are common in Slovenia, sing very loud and are easy to recognize are:

Common Cicada Lyristes plebejus (Scopoli, 1763)

Ash Cicada Cicada orni Linnaeus, 1758

Vineyard Cicada Tibicina haematodes (Scopoli 1763)

In the Karst area, we can hear and find the Silvery Cicada Tettigettalna argentata (Olivier, 1790). 

The song of the Pygmy Cicada Tettigettula pygmea (Olivier, 1790) (=brullei (Fieber, 1876))  has most energy in the spectral range between 16 and 20 kHz (see sonogram below) and can thus be heard with no aid of an ultrasonic detector only at a close range (up to 1 or 2 m). The song is described in detail in the journal Acta entomologica slovenica 5(2): 89-101 (1997).

The Cicada Dimissalna dimissa (Hagen 1856) has a complex continual song pattern and can be heard with the naked ear.

The Mediterranean Cicada Cicadetta mediterranea Fieber 1876 has two different phrases (1, 2). This species can be found in grass and other green plants in the coastal region of southern Istria. The article, which describes its song in detail, was published in the journal Acta entomologica slovenica 5(1): 

The New Forest Cicada Cicadetta montana s. str.(Scopoli 1772) is a species that can also be found in colder parts of Europe and Slovenia.

In Slovenia, we have found another so far unidentified related species, which will be presented in the future.

Cicadivetta tibialis (Panzer 1798) is yet another small cicada species with two high frequency songs. The time pattern of the first song resembles the pattern of C. mediterranea, whereas the second song is of very dissimilar and simpler structure. A detailed description of this species’ song was published in the journal Acta entomologica slovenica 4(2): 45-62 (1996).

Listen to the songs of European cicadas

Some fascinating songs performed by cicadas from Southeast Asia (Matija Gogala & Tomi Trilar)

Loud singing insects – cicadas – demonstrate a high diversity of form, colour and sound signals in Southeast Asia. In the last few years, I and my colleagues from the Slovenian Museum of Natural History in Ljubljana have visited this region a few times and recorded several fascinating cicada songs. Here is a modest selection from the rich background music, pertinent only to the remains of Southeast Asian disappearing rainforests.

The presented digital audio recordings originate mostly from Thailand and Malaysia. More songs from Borneo (Sabah, Sarawak) can be found on the homepage of Klaus Riede from Germany.

The identified cicada species

• The song of the species Purana nebulilinea from Peninsular Malaysia has long sequences (about 1 minute) of high-frequency song with characteristic frequency modulation that can be repeated several times with no interruption (Kos and Gogala, 2000).
• Listen to the song of Purana sagittata from Gombak and Temengor Forest Reserve (Perak, Peninsular Malaysia) and, for comparison, from Endau Rompin National Park (Peninsular Malaysia) (Trilar and Gogala, 2002).
• The next example of a long complex song is the song of Purana metallica from Ko Tarutao Island (Thailand). The whole repetitive sequence, which is rhythmically very complex, was first described by Gogala (1995) under the name Purana aff. tiger. The description of the species under the name Purana metallica was followed by a detailed description of its song (Trilar and Gogala, 2007).
• The Singing Cicada with the most complex known song in the Purana genus is Purana latifascia from Kampong Lubu (Sabah, Borneo). Long phrases of high-frequency singing comprise no less than three different sequences with frequency modulation, which follow each other in a characteristic order (Trilar and Gogala, 2007).
• Cicadas of the genus Maua are related to those of the genus Purana, which one can also observe in their songs’ structure. Watch a video of the singing Mau albigutta from Endau Rompin National Park (Gogala et al., 2004).
• “Tii-tii-tuy” (Meimuna tavoyana) from Doi Suthep (Chiang Mai, Thailand) is also described in the work Gogala, 1995.
• The Yellow-banded Cicada Tacua speciosa, photographed in Kinabalu National Park (Sabah, Borneo), is presented here with a short sequence of its song, which normally lasts for over 10 minutes.
• The song of the species Kalabita operculata is also described from Kinabalu National Park (Sabah, Borneo) (Trilar, 2006).

Author: Matija GOGALA, Ljubljana

The article carrying this title was published  in Muzikološki zbornik (Musicological Bulletin), 33 (1997): 5-21, published in Ljubljana, Slovenia.

Several examples of animal sounds or vibration signals referred to in this article are presented in the form of oscillograms and sonograms. For a better notion of this communication, the  following examples of animal sounds and vibration signals are presented.

Numerous insects produce vibration signals and tunes, most interesting among them being those produced by true bugs (Heteroptera) of the Cydnidae family. They do so by two different mechanisms, stridulation, rubbing together serrated body parts, body shaking, or with the simple timbal. For their communication, only the vibrations on the ground are important, not the sound transmitted through the air.

Our example is the Pied Shieldbug (Tritomegas bicolor).

As soon as touched, attacked or otherwise disturbed, this species produces, by stridulation, short irregularly repeating stridulation signals, called excitation signals.

Of greater interest are the vibrational songs that can be heard during the insects’ courtship and mating. Males produce the first courtship song (MS-2) with repeated phrases consisting of a low-frequency part, followed by three or four stridulatory sounds. If the female is ready to mate, she will respond with a long sequence of short stridulation signals (FS-2). After a while, the male shifts to an intense second courtship song (MS-3). These signals can be heard as an entire sequence and can be seen individually in the following illustrations:

The second related bug is Sehirus luctuosus. The male’s (vibrational) courtship song is highly reminiscent of a jazz musician’s drum solo.

The following interesting example is the acoustic behaviour of the predatory species Phymata crassipes. 

This species produces several vibration songs. One of them is used alternately by males, females and even juveniles. Let us listen to two alternating individuals. These bugs also respond with this kind of vibrational signals to various sounds and even to human speech or whistling and copy the duration of such sounds. You can listen to this kind of alternation between the bug (Ph) and the performer of the test (H), and see the sonagram below:

Even more surprises wait for us in the acoustic world of tropical and subtropical countries  – where the endangered natural ecosystems still exist. The author had the opportunity to study the fascinating songs of Southeast Asian cicadas and the sounds of other animals in the rainforests of Malaysia and Thailand.

Contrary to European cicadas, some species sing there like birds with a high degree of frequency modulation, which sounds like this:

The number of singing cicadas is so high in certain places that they have to share their singing time with other species in a precise order to make the communication effective. For this reason, the sounds in rainforests change from hour to hour, as shown in the following examples from  Belum Forest in Malaysia.

Belum 1 in the morning, Belum 2 before noon, Belum 3 in the afternoon, Belum 4 in the evening, and Belum 5 at night.

More examples of songs produced by tropical cicadas can be heard on the page with Asian cicadas.

Several tropical bird songs are surprising, too. Some are sung major or minor scales up (a) or down (b) like Myiophoneus caeruleus (a – see below!)

An example of the extremely complex and fantastically coordinated animal singing, which I heard and recorded in Taleban National Park (Thailand), was the singing by two gibbons in polyphony. Let us listen to a short excerpt of this consonant glissando, which is also presented on the graph below.

The author, a biologist with some musical education and experience gained in working in  bioacoustics for more than 40 years. He wishes to present examples of his research, mainly insects, as well as other animals, particularly the attributes of animal sounds, which are additionally interesting from a musical point of view. Very diverse acoustic signals are presented, together with the variability of animal songs and the presence of certain musical elements in these patterns. In animal songs, we can find complex patterns and rhythms, equable alternation, imitation of other sounds, the tonal modes singing, singing in harmony with other specimen or specimens, and even a sort of dance with the rhythm of one’s own song.

 

Summary

The bulk of the examples presented in the first part of this article deals with vibrational songs of European bud species (Insecta: Heteroptera), whereas in the second part, the songs of animals (cicadas, birds and mammals) were recorded in the tropics. The biodiversity of tropical rainforests is mirrored in the wealth of sound backgrounds, particularly in Southeast Asia. The author was all the more impressed during his expeditions by the sonic diversity of tropical cicadas, with an unusually high degree of frequency modulation for insects and many species singing exclusively during specific hours of the day or night. These countries are also inhabited by a series of birds that sing up and down the scales and gibbons that sing in polyphony. The entire sound background of an undisturbed tropical rainforest is an endless symphony of nature, changing from hour to hour, and culminating at dusk.

A number of cassettes and CDs have been produced with recordings of sound backgrounds or with selected animal sounds  –  as a replacement of adventures in nature, for meditation, as an interesting soundtrack or for scientific purposes. Some composers utilize recordings of animal sounds as a source of new ideas or even as material for bioacoustic compositions*). The digitized audio examples used in this article are available on this website. Perhaps, however, it would be best just to listen carefully to all these voices in nature.

*) As an example, let us listen to the “bioacoustic composition” titled Touches by the composer Boštjan Perovšek. This piece includes the sounds of synthesizer, accordion, and the voices of over 16 species of crickets, cicadas, bugs, bees, birds, frogs and toads.