Barrier reefs may provide a high wave energy natural refuge for large-sized endangered parrotfish species in the Caribbean

Marine herbivorous fishes such as parrotfish are critical for coral reef resilience through algal control. Overfishing and illegal fishing have brought a substantial decline in parrotfish populations across the Caribbean. The absence or limited abundance of large-sized parrotfish species has resulted in some species being categorized as endangered in the Seaflower Biosphere Reserve (SBR). Surf zones at coral barrier reefs impede access for fishers creating natural protection from fishing pressure. This research summarizes the results of fish censuses conducted at different areas of the coral barrier reef, San Andrés Island, SBR. We compare high wave energy and exposure sites with historical census results (2013–2022) from sampling areas with low wave energy exposure, where Scarus coelestinus was totally absent, and S. guacamaia was very scarce (0.025 ind/100 m2), and find considerably higher presence and abundance of these two large-sized parrotfish species, S. coelestinus (0.333 ind/100 m2), and S. guacamaia (0.633 ind/100 m2) in the shallow forereef and reef crests with high wave energy exposure. These results suggest that high wave energy sites provide natural protection for endangered large-sized parrotfish during most of the year and provide science-based support for protection of coral barrier reefs as a natural refuge for endangered species across the SBR and the Caribbean.