Effects of anthropogenic pressures on the seagrass Halophila stipulacea and its associated macrozoobenthic communities in the northern Gulf of Aqaba

Abstract

Halophila stipulacea is a tropical seagrass species, native to the Red Sea, Persian Gulf, and Indian Ocean, while invasive to the Mediterranean and Caribbean Seas. The benthic fauna assemblages associated with H. stipulacea in its native habitats and the potential effects of anthropogenic stressors on these assemblages remain unknown. We compared meadow characteristics, associated fauna assemblages and trophic niche structures of H. stipulacea from an impacted and a pristine site in the northern Red Sea. Seagrass cover and biomass were higher in the impacted site, however, the associated fauna community was more abundant and diverse in the pristine site. Both meadows showed comparable trophic niches based on stable isotope analysis. This study provides first insights into the macrozoobenthos associated with H. stipulacea in its native habitat and highlights the importance of better understanding the relationship between seagrasses and their associated biota and the potential effects of urbanization on this relationship.

Keywords: Anthropogenic impact; Gulf of Aqaba; Macrozoobenthic community; Seagrass; Stable isotope; Trophic structure.