Acoustic propagation in heterogeneous environments and communication networks in rock ptarmigan
Acoustic propagation supports long-distance animal communication. However, attenuation processes also constrain the range of vocalizations. In this regard, the active space is a central bioacoustic concept to understand animal communication networks in the wild. In parallel, detection space determin...
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Other Authors: | , , , , , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
HAL CCSD
2023
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Subjects: | |
Online Access: | https://theses.hal.science/tel-04301057 https://theses.hal.science/tel-04301057/document https://theses.hal.science/tel-04301057/file/TH_2023ECDL0027.pdf |
Summary: | Acoustic propagation supports long-distance animal communication. However, attenuation processes also constrain the range of vocalizations. In this regard, the active space is a central bioacoustic concept to understand animal communication networks in the wild. In parallel, detection space determines the possibilities of recording biological data in ecoacoustic studies. Propagation of animal acoustic signals has mostly been studied by considering the natural environment as an homogeneous propagation medium. This resulted in an simplified circular active space representation that is still widely used. Only few studies have assessed the variations of the active space due to environment heterogeneities and transmitter position. This thesis provides an integrative approach at the interface of bioacoustics and atmospheric propagation to robustly estimate active and detection spaces in rock ptarmigan, an emblematic species of the high mountains. For this purpose, we develop a stable and flexible tool to investigate the organization of communication networks as well as population densities and their dynamics. This tool is based on the numerical computation of the parabolic equation for acoustic propagation in the atmosphere, and takes into account topography, ground effects and weather conditions. This thesis work consists of three parts: (i) a validation of the acoustic propagation code in a heterogeneous environment, (ii) an application of the model to the study of a communication network, and (iii) an application to the detection spaces for passive acoustic monitoring. First of all, comparisons of numerical simulations with measurements performed during an experimental campaign in the French Alps confirms the capacity of the code to accurately predict sound levels. We then use this model to show how mountain conditions affect surface and shape of active spaces, with topography being the most significant factor. The model is then applied to an ecological context using field data including a site of known topography, ... |
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