Evaluating the effectiveness of artificial reefs in enhancing fisheries productivity and biodiversity in the Sea of Oman

Abstract

Marine artificial reefs (ARs) play a crucial role as submerged structures in ocean environments, aimed at habitat restoration, fostering marine biodiversity, and enhancing fisheries. This study, conducted in the Sea of Oman near Sohar, Sultanate of Oman to evaluate the effectiveness of ARs in enhancing local fisheries. Utilizing diver-operated video (DOVs), Baited Remote Underwater Stereo-Video (BRUVs), and fish traps, the study assessed fish communities in terms of abundance and biomass across various AR sites. The findings revealed that shallow and older ARs (11–13 m, approximately 20 years old) exhibited higher catch per unit effort (CPUE) compared to adjacent deep natural reefs (20–22 m) and middle-aged sites (approximately 15 years old), indicating the positive impact of ARs on fisheries productivity. Both summer and winter surveys consistently showed the highest number of individuals on shallow and deep ARs. Non-metric multi-dimensional scaling (NMDS) analyses highlighted distinct fish assemblages at ARs compared to nearby natural reef sites. The study identified Lutjanus spp. as a significant fisheries species, particularly abundant on deeper ARs. Various fish families, such as Lutjanidae and Carangidae, were recorded using different survey methods, emphasizing the importance of employing diverse assessment techniques. This study underscores the time-sensitive maturation of ARs for optimal productivity and highlights the necessity of employing multiple assessment methods to comprehensively investigate fish communities' abundance, biomass, and diversity in the Sohar region of the Sultanate of Oman.