The importance of macroalgal ecosystems in tropical reef fisheries
In tropical marine ecosystems, macroalgal reefs provide an important habitat for a range of fish species, which includes species targeted by fisheries. Dr Luke Barrett recently contributed to a study led by Dr Shaun Wilson to understand how macroalgal habitats can contribute to small-scale reef fisheries. The authors found that across 133 small-scale fisheries, macroalgal-associated fish species comprised 24% of the total catch, although very few fished species relied entirely on macroalgal or coral habitats post-settlement. Further, macroalgal and coral-associated fishes had similar life-history traits, although vulnerability to fishing declined with increasing contribution of macroalgae associated to the catch, while mean trophic level and diversity peaked when macroalgal-associated fish accounted for 20-30% of catches. A case study in the Seychelles examining how tropical fisheries can change with the expansion of macroalgal habitats demonstrated that the biomass of primary target species increased as macroalgae cover expanded. Overall, the results highlight the importance of multiple habitat types on supporting tropical fishery sustainability and stability, emphasising the need to protect both coral and macroalgal ecosystems in the tropics.