Skip to Main content Skip to Navigation
Theses

Développement d’indices écoacoustiques pour caractériser et suivre l’état et le fonctionnement des écosystèmes coralliens

Abstract : Coral reefs are the most complex of marine ecosystems, but also the most threatened by ecological disruption resulting directly or indirectly from human activities. Their conservation represents a huge challenge. While maintaining coral reefs as close as possible to their current configurations and dynamics is among the highest priorities, we must also prepare for rapid changes in their functioning and adapt monitoring tools and networks to this new situation. Recent technological advances enabled the emergence of innovative tools with the potential to drastically increase the spatio-temporal resolution of coral reef monitoring. Among these, Passive Acoustic Monitoring (PAM) is on the rise. The aim of this thesis was to improve and facilitate the use of PAM as a tool for the assessment and monitoring of coral reefs’ ecological states and functioning. Soundscape recordings and ecological surveys (reef fish assemblages and habitat) were performed at 31 outer reef slope sites around three Indo-Pacific islands with variable environmental characteristics, including contrasted anthropogenic pressures. Analysing the results obtained with multiple combinations of sampling settings (frequency bandwidth, time of sampling (day/night), and sample duration) allowed the selection of a sampling scheme based on the two types of indices mostly used in coral reef studies. This scheme enables a rapid and reliable categorisation of reef’s ecological states. Based on these sampling guidelines, the capacity of six ecoacoustic indices to evaluate coral reef key functions was demonstrated. By comparing the contributions of PAM and coarse environmental data that could be sampled remotely, the added value of using ecoacoustic indices to predict reef fish assemblage structure was identified and quantified. An application of ecoacoustics to the continuous monitoring of a remote site highlighted the strong potential of PAM as a supporting tool for managers in such context. In view of the amplitude and velocity of expected climatic changes, current observer-based monitoring methods are likely to be exceeded. Combined to other monitoring tools, PAM could contribute to promptly detect ecosystem disturbances, which is essential to understand their causes and put in place rapid and adapted responses.
Complete list of metadatas

Cited literature [277 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02900693
Contributor : Abes Star :  Contact
Submitted on : Thursday, July 16, 2020 - 12:55:12 PM
Last modification on : Tuesday, October 20, 2020 - 3:05:05 AM

File

2019lare0041_SElise.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02900693, version 1

Citation

Simon Élise. Développement d’indices écoacoustiques pour caractériser et suivre l’état et le fonctionnement des écosystèmes coralliens. Biodiversité et Ecologie. Université de la Réunion, 2019. Français. ⟨NNT : 2019LARE0041⟩. ⟨tel-02900693⟩

Share

Metrics

Record views

88

Files downloads

86