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Groupers are marine fishes particularly vulnerable to overexploitation owing to their reproduction‐related traits. The dusky grouper Epinephelus marginatus is classified as 'Endangered' in the Mediterranean Sea, where protection measures have proven critical for allowing population recovery and persistence of the species. However, knowledge gaps remain regarding its reproductive behaviours and spawning sites. As with other grouper species, the dusky grouper is known to produce courtship‐associated sounds, which were validated in captivity, but no study has ever established a link between sound production and observed behaviours in the wild.This study aims to characterize, both visually and acoustically, the behavioural patterns of wild dusky grouper, thus specifically linking visual courtship behaviours to the associated sound production. Visual as well as passive acoustic methods were employed at two presumptive spawning sites within a Mediterranean Marine Protected Area (MPA) in the north‐western Mediterranean Sea over two consecutive summer seasons (2017 and 2018).The temporal patterns of sound production showed site specificity over the month in which reproductive activity was most intense. Courtship calls were mostly recorded around sunset at both study sites and were significantly associated with visual reproductive behaviours. Results also indicated a temporal partitioning in the acoustic activity of the species, with different sound types being recorded at distinct times of the day, likely corresponding to the occurrence of various behaviours during those periods.These findings have important implications for identifying and monitoring dusky grouper spawning sites using passive acoustic methods, therefore providing valuable information for the development, implementation, and/or enforcement of effective conservation measures therein. [ABSTRACT FROM AUTHOR]

The article focuses on the measurement and analysis of ship acoustic signatures, specifically examining the variability in these signatures based on hydrophone configuration. Topics discussed include the importance of understanding underwater noise pollution from maritime transport, the challenges in adhering to measurement protocols, and the identification of biases in acoustic measurements at low frequencies.

The article focuses on the Marine Acoustic Research Station (MARS) project's efforts to collect and analyze ship acoustic signatures to address the issue of underwater noise pollution caused by merchant ships in the Saint Lawrence Estuary. Topics discussed include the methodology used by the MARS station to gather acoustic signatures, the comparison of these signatures with existing databases, and the importance of this data for mitigating ship-generated underwater noise.

The article focuses on assessing the repeatability of underwater acoustic signature measurements from ships in the context of addressing ocean noise pollution. Topics discussed include the Marine Acoustic Research Station (MARS) project's efforts to collect high-quality acoustic signatures, the analysis of repeated measurements, and the preliminary findings indicating a high level of measurement reliability, particularly for ships following specific measurement protocols.

The article focuses on using onboard vibration and underwater acoustic data, highlighting the Demon (Detection of Envelope Modulation On Noise) and ICMC (Integrated Cyclic Modulation Coherence) algorithms. It aims to assess propeller cavitation inception speed (CIS) and reduce underwater noise pollution in maritime settings. Topics covered include concerns about rising ship-related underwater noise, algorithm development for cavitation detection and CIS estimation.