The song of the species: new tool for the study of climate change

The sounds used by animals to communicate have been a powerful study tool in ecology and related sciences. Songs, trills, chirps and various vocalizations emitted by birds, mammals, amphibians or insects contain valuable information for scientists who strive to capture these signals and decipher their meaning.

Now, thanks to the use of new acoustic monitoring technologies, a group of researchers from the Autonomous University of Madrid (UAM), the University of Alcalá de Henares (UAH), the Zoological Fonoteca of the National Museum of Natural Sciences (MNCN), the University of Seville and the Federal University of Goiás, the latter institution in Brazil and the others in Spain, have shown that these sounds can offer clues about the effects of climate change on the behavior of animal species.

Specifically, by combining automatic sensors and voice recognition algorithms with mathematical models, the team, led by Diego Llusia and Camille Desjonquères from the UAM, has developed a method that makes it possible to examine how the reproduction rhythms or the distribution areas of the species and predict the long-term impact that climate change could have on their populations.

The song of the frog of San Antón

There are many species that use acoustic communication to perform essential functions, such as reproduction, defense of territories or the search for food. If changes in the rainfall and temperature regime restrict or alter the conditions necessary for carrying out these behaviors, it is to be expected that the species may suffer changes in their patterns of activity and geographic distribution or even see their survival compromised on a global scale. local or regional.

The methodology was evaluated for the first time in an autochthonous species of the Iberian Peninsula, the San Antón tree frog (Hyla molleri), whose individuals use song to find reproductive partners.

“The models developed have given rise to promising results, by robustly predicting the vocal activity of this species based on climatic conditions”, the authors of the study affirm.

“The method -they add- thus offers the possibility of calculating the ecological requirements of the song of the species and, according to different future scenarios, estimating the probability that the animals will find suitable conditions to carry out their vital functions throughout the territory or the seasons of the year.

In short, these results provide an innovative tool to identify possible changes in the phenology and distribution of species in the current context of climate change.

Bioacoustics and biogeography

Various modeling techniques exist to predict the response of species to climate change, but they have some limitations. The proposed method aims to provide a new source of information that improves our ability to understand the consequences of climate change, placing special emphasis on animal behavior.

To address this challenge, researchers have proposed a novel integration between two scientific disciplines: bioacoustics and biogeography.

The first offers a wide range of knowledge and techniques to monitor animal populations throughout their distribution area through the use of acoustic sensor networks, small sound recorders that automatically record the song of the species.

The subsequent analysis of the extensive bank of recordings obtained with this equipment requires the use of recognition algorithms that automatically detect the periods of vocal activity of the species. Finally, biogeography makes spatial modeling tools available to understand how study animals are affected by changes in climatic conditions.

Automatic recorder installed in the field to record the vocal activity of amphibian populations (Photo: Diego Llusia)

For researchers, the growing concern about climate change and its effects on the planet requires an improvement in study tools. Only in this way will it be possible to understand the impacts that these changes have on biodiversity and better understand how the rhythms and dynamics of nature are being altered.

“This innovative line of research will continue to be developed in the coming years by our team, international pioneers in the field of bioacoustics. Although it should be noted that what is essential and most urgent is the implementation of measures that help mitigate these effects, with the application of decisive political actions and the awareness and commitment of citizens to reduce our carbon emissions to the atmosphere”, the authors conclude.

The study is entitled “Acoustic species distribution models (aSDMs): A framework to forecast shifts in calling behavior under climate change”. And it has been published in the academic journal Methods in Ecology and Evolution. (Source: UAM)