Despite hosting some of the highest concentrations of biodiversity and providing invaluable goods and services in the oceans, coral reefs are under threat from global change and other local human impacts. Changes in living ecosystems often induce changes in their acoustic characteristics, but despite recent efforts in passive acoustic monitoring of coral reefs, rapid measurement and identification of changes in their soundscapes remains a challenge. Here we present the new open-source software CoralSoundExplorer, which is designed to study and monitor coral reef soundscapes. CoralSoundExplorer uses machine learning approaches and is designed to eliminate the need to extract conventional acoustic indices. To demonstrate CoralSoundExplorer's functionalities, we use and analyze a set of recordings from three coral reef sites, each with different purposes (undisturbed site, tourist site and boat site), located on the island of Bora-Bora in French Polynesia. We explain the CoralSoundExplorer analysis workflow, from raw sounds to ecological results, detailing and justifying each processing step. We detail the software settings, the graphical representations used for visual exploration of soundscapes and their temporal dynamics, along with the analysis methods and metrics proposed. We demonstrate that CoralSoundExplorer is a powerful tool for identifying disturbances affecting coral reef soundscapes, combining visualizations of the spatio-temporal distribution of sound recordings with new quantification methods to characterize soundscapes at different temporal scales. Author summary: Passive acoustic monitoring is an increasingly popular method for monitoring ecosystems, but analyzing the data generated by this approach remains complex. In this paper, we present CoralSoundExplorer, a tool for analyzing large sets of sound recordings. The tool is open source and has been designed to be easy to use, even by non-specialists, thanks to a graphical interface. This graphical interface is also available in an online version to allow users to visualize previously processed data without needing to install the software. The CoralSoundExplorer software transforms recordings of coral reef soundscapes into visual representations using UMAP embeddings coupled with tools for quantifying phenomena. By projecting sound samples into acoustic spaces, CoralSoundExplorer enables the observer to grasp the characteristics of the soundscapes, their differences and similarities and their organization on different temporal scales. These acoustic spaces and their temporal dynamics can be quantified, for example to account for the speed at which soundscapes change over time or to identify clusters of sound samples on the basis of their acoustic similarities. We use an example of the reef soundscapes of the island of Bora-Bora to present and illustrate the functionalities of our software, confirm previous findings, provide new insights, and demonstrate the applicability of the software for the analysis of large datasets. Based on the Bora-Bora dataset, we also provide a parametric study of CoralSoundExplorer to show the effects of its different settings on the analysis results. Detailed instructions for installing and using the software are also provided in the supplementary materials S3 Text. [ABSTRACT FROM AUTHOR]

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