Aircraft noise modifies acoustic signals and social interactions of a microendemic frog from Mexico City

Abstract

AbstractResearch on urban noises affecting acoustic communication of animals is a growing area of study and conservation concern. However, the consequences of aircraft noise on anuran acoustic communication have been explored on a restricted basis to date. In this study, we investigated the impact of aircraft overflights on the individual and chorus performance of acoustic signalling in the Pedregal frog (Eleutherodactylus grandis), a microendemic and threatened species from Mexico City. During the summer of 2021, we recorded acoustic signals from male individuals and conducted acoustic monitoring to analyse how chorus social interactions change due to aircraft overflights. For this purpose, we evaluated acoustic properties of the call, including call duration, dominant frequency, call amplitude, and call repetition rate. Additionally, we measured the amplitude of environmental noises and signals by means of two types of complementary methodological approaches. Our results show changes in the individual performance of acoustic signals with longer call duration, lower dominant frequency, and higher call amplitude due to aircraft overflights, while individual call repetition rate did not vary. Furthermore, a decrease in the number of calls within the chorus was observed during aircraft overflight. Overall, these results show that aircraft noise causes plastic changes in the acoustic signals of the Pedregal frog and that social interactions between conspecifics decrease, thus adding a new disturbance to this species that already suffers from other anthropogenic noises, and habitat fragmentation.