Climatic breadth of calling behaviour in two widespread Neotropical frogs: Insights from humidity extremes

Abstract

Climate change is severely altering precipitation regimes at local and global scales, yet the capacity of species to cope with these changes has been insufficiently examined. Amphibians are globally endangered and particularly sensitive to moisture conditions. For mating, most amphibian species rely on calling behaviour, which is a key weather‐dependent trait. Using passive acoustics, we monitored the calling behaviour of two widespread Neotropical frogs in 12 populations located at the humidity extremes but thermal mean of the species distribution. Based on 2,554 hr of recordings over a breeding season, we found that both the aquatic species Pseudis paradoxa and the arboreal species Boana raniceps exhibited calling behaviour at a wide range of relative humidity. Calling humidity was significantly lower in conspecific populations subjected to drier conditions, while calling temperature did not differ between populations or species. Overall, no variation in climatic breadth was observed between large and small choruses, and calling behaviour was scarcely detected during the driest, hottest and coldest potential periods of breeding. Our results showed that calling humidity of the studied species varies according to the precipitation regime, suggesting that widespread Neotropical anurans may have the capacity to exhibit sexual displays in different climatic environments. Regardless of the underlying mechanism (plasticity or local adaptation), which should be determined by common garden experiments, a wide and population‐specific climatic breadth of calling behaviour may assist species to deal with changing humidity conditions. To our knowledge, this is the first study to explore the response capacity of anurans to perform calling behaviour under contrasting precipitation regimes.

Acoustic species distribution models (aSDMs): A framework to forecast shifts in calling behaviour under climate change

“…cold vs. warm extremes; dry vs. wet extremes, or sites with distinct multi‐dimensional parameters identified with a clustering approach), hence covering most of the range of climatic variation experienced by the study species to approach the environmental breadth of their calling behaviour. It has been demonstrated that examining the performance of the study species at contrasting climatic conditions can contribute substantially to assess the influence of climate on calling behaviour, even when monitoring only two populations (Bonnefond et al, 2020; Llusia, Márquez, Beltrán, Benítez, et al, 2013; Llusia, Márquez, Beltrán, Moreira, et al, 2013).…”

“…In combination with niche modelling, these novel techniques may assist researchers in providing a basis for the development of new species distribution models: aSDMs. Recent studies have shown how acoustic monitoring can be used to estimate climatic breadth and environmental suitability for calling behaviour (Bonnefond et al, 2020; Llusia, Márquez, Beltrán, Benítez, et al, 2013), laying the foundations for aSDMs. These estimates constitute a novel source, not only of eco‐physiological information to model species distribution, but also behavioural and phenological information, improving our tools to predict past, present and future environmental suitability for vocal animals.…”

BASSA: New software tool reveals hidden details in visualisation of low‐frequency animal sounds

“…Many of these fields have adopted other methods. While there has been at least one study highlighting the issues with the STFT spectrogram in the study of animal sounds (Brumm et al., 2017 ), this remains the most common method in the biological sciences (Baotic et al., 2014 ; Benko & Perc, 2009 ; Bonnefond et al., 2020 ; Bussmann et al., 2021 ; Cazau et al., 2016 ; Davenport et al., 2022 ; Dutour et al., 2021 ; Forti et al., 2017 ; Gonzalo‐Tarodo et al., 2020 ; Jégh‐Czinege et al., 2020 ; Leroy et al., 2021 ; Malige et al., 2020 ; Mann et al., 2021 ; Maruska & Mensinger, 2009 ; McDonald et al., 2009 ; Nelson et al., 2011 ; Odom et al., 2021 ; Rice & Bass, 2009 ; Salas et al., 2018 ; Staniewicz et al., 2023 ; Stoeger et al., 2014 ; Sueur et al., 2011 ; Teixeira et al., 2022 ; Thode et al., 2017 ).…”