Passive acoustics reveals environmental drivers of dusky grouper reproductive activity to inform MPA planning

Abstract Understanding the reproductive behavior of key marine species is essential for effective management of marine protected areas (MPAs). This study investigates the reproductive activity of the dusky grouper (Epinephelus marginatus), a vulnerable species in the Mediterranean Sea, through passive acoustic monitoring (PAM). Over a 3-year period, we recorded and analyzed vocalizations associated with courtship and territorial behaviors in a grouper aggregation hotspot within the Tabarca Island MPA. Our results reveal distinct temporal patterns in vocalization rates, peaking during the summer reproductive season, and show that environmental factors such as turbidity, seabed temperature, photoperiod, and wind significantly influence reproductive sound emissions. This study demonstrates that PAM is a valuable tool for monitoring reproductive behavior and offers practical insights for improving MPA management, ensuring the protection of critical habitats and enhancing the reproductive success of E. marginatus.